Intravital Imaging of Leukocyte-Endothelial Interaction in Hindlimb Ischemia/Reperfusion Injury by Intravital Multiphoton Microscopy

Ischemia/reperfusion injury in skeletal muscle leads to sterile inflammation and affects structure and function permanently. However, the main understanding of the molecular and cellular mechanisms mainly relies on in vitro and ex vivo investigations. Recent advances in intravital microscopy allow for insights into dynamic processes at the cellular and subcellular level under both physiological and pathophysiological conditions. Real-time intravital imaging by two-photon microscopy (2P-IVM) has emerged as a powerful tool in the evaluation of the cell-cell interaction and molecular biology of leukocytes in live animals. Acute ischemic injury in limbs may occur due to crush syndrome, compartment syndrome, and vascular diseases and injury as in acute peripheral arterial occlusion, caused by a diverse array of pathological conditions. Iatrogenic revascularization and restoration of perfusion results paradoxically in aggravated tissue injury. Furthermore, the effects of IR-injured skeletal muscle in clinical conditions such as compartment syndrome or crush syndrome may induce rhabdomyolysis and are associated with so-called remote injuries as acute kidney dysfunction. Here, we discuss the considerations for and describe a 2P-IVM method designed for visualization of leukocyte-endothelial interaction. This chapter will provide a detailed experimental setup and a step-by-step protocol for the dynamic imaging of leukocyte-endothelial-interaction in an ischemia/reperfusion injury model.

Secondary dynamic midface reanimation with gracilis free muscle transfer after failed reconstruction attempt: A 15-year experience

BACKGROUND

The quantitative outcome of secondary reanimation after a failed primary reconstruction attempt for facial paralysis is rarely reported in the literature. This study aimed to investigate the feasibility of secondary reanimation with gracilis free muscle transfer (GFMT) and whether this outcome is influenced by the primary reconstruction.

METHODS

Twelve patients with previously failed static procedures (static group, n = 6), temporal muscle transfer (temporal transfer group, n = 2), and GFMT (GFMT group, n = 4) were all secondarily reanimated with GFMT. The clinical outcome was graded with the eFACE metric. The objective oral commissure excursion was measured with Emotrics, and the artificial intelligence software FaceReader evaluated the intensity score (IS) of emotional expression.

RESULTS

The mean follow-up was 40 ± 27 months. The eFACE metric showed a statistically significant (p < 0.05) postoperative improvement in the dynamic and smile scores across all groups. In the GFMT group, oral commissure with smile (75.75 ± 20.43 points), oral commissure excursion while smiling with teeth showing (32.7 ± 4.35 mm), and the intensity of happiness emotion while smiling without teeth showing (IS of 0.37 ± 0.23) were significantly lower as compared with the static group postoperatively (98.83 ± 2.86 points, p = 0.038; 41.7 ± 4.35 mm, p = 0.025; IS 0.83 ± 0.16, p = 0.01).

CONCLUSIONS

Our data suggest that secondary dynamic reconstruction with GFMT is feasible should the primary reconstruction fail. The secondary GFMT appears to improve the outcome of primary GFMT; however, the oral commissure excursion while smiling might be lower than that in patients who had static procedures as primary reconstruction.

The esthetic outcome of recipient sites of gracilis muscle flaps versus anterolateral thigh flaps: A retrospective study

BACKGROUND

Anterolateral thigh (ALT) and gracilis muscle flaps have been described as comparable reconstructive options regarding maximal flap dimension and indications. However, split-thickness skin-grafted muscle flaps are generally believed to be inferior to perforator flaps regarding the esthetic outcome of the recipient site. The purpose of this study was to challenge this assumption, comparing the long-term esthetic outcome of the gracilis and the ALT flap.

METHODS

One hundred forty-eight patients who had undergone free flap reconstruction with either free split-thickness skin-grafted gracilis muscle flaps (n = 86) or ALT flaps (n = 62) were evaluated in the study. Patients' satisfaction with the esthetic outcome, rates of flap loss, wound healing disorders and the necessity for thinning the flap or scar correction procedures were assessed.

RESULTS

Flap loss occurred in 4 of 86 gracilis flaps (4.7%) and 2 of 62 (3.2%) ALT flaps (p > .9999). Thinning or scar correction procedures were necessary for 6 of 86 gracilis (7.0%) and 4 of 62 (6.5%; p > .9999) ALT flap recipient sites. Regarding the overall patients' satisfaction with the esthetic outcome, scores were similar in both groups (2.667 [ALT] vs. 2.348 [gracilis]; p = .3739). Contour deformity, scar hypertrophy, and difference in flap color/texture in relation to the surrounding skin were comparable throughout the ALT and gracilis group (2.667 vs. 2.174, p = .2099; 3.333 vs. 2.739, p = .0912 and 2.500 vs. 2.174, p = .3159, respectively).

CONCLUSION

The gracilis and ALT flap are two equivalent reconstructive options regarding the esthetic outcome of the recipient site and long-term patient satisfaction.

Age-related outcomes of facial reanimation surgery using gracilis free functional muscle transfer innervated by the masseteric nerve: A retrospective cohort study

BACKGROUND

The free functional muscle gracilis transfer is an established approach in facial reanimation surgery; however, the significance of its neurotization and the patient's age is still inconclusive. Several donor nerves are available for facial reanimation using the free functional gracilis muscle transfer.

OBJECTIVE

This retrospective cohort study investigates whether the masseteric nerve is an equally reliable donor nerve in both older and younger patients.

METHODS

We included 46 patients (13-71 years, male and female) who underwent nerve-to-masseter (NTM)-driven free functional muscle transfer (FFMT) between January 2008 and December 2019. Patients were distributed into three cohorts according to their age at surgery. We assessed the facial symmetry before and after surgery using the pupillo-modiolar angle. Commissure height and excursion deviation were measured with the Emotrics software. Patient-reported outcome measurements were taken using the Facial Clinimetric Examination (FaCE) scale.

RESULTS

All patients had successful flap innervation, except for one patient in the middle-aged cohort (31-51 years). The postoperative facial symmetry at rest, smiling, and laughing was analyzed with the pupillo-modiolar angle and the Emotrics software and showed similar results between all cohorts. The FaCE scale showed similar scores for the middle-aged (31-51 years) cohort and the senior cohort (52-71 years). The social function score in the senior cohort was higher than in the middle-aged cohort, without statistical significance. One patient in the middle-aged (31-51 years) cohort and the senior cohort (52-71 years), respectively, underwent emergency revision due to impaired flap perfusion and could be salvaged.

CONCLUSIONS

NTM-driven FFMT for facial reanimation is a safe and reliable procedure across all age groups of patients.

Special Issue: Evidence-Based Diagnosis and Management of Facial Nerve Disorders

Although there has been a rapid increase in the number of new publications and studies in relation to the diagnostics, impacts and rehabilitation methods of facial nerve disorders, a general structure in evidence-based medicine is still difficult to establish [...].

Functional Outcome of Dual Reinnervation with Cross-Facial Nerve Graft and Masseteric Nerve Transfer for Facial Paralysis

BACKGROUND

The combination of cross-facial nerve graft (CFNG) and masseteric nerve transfer (MNT) for reinnervation of facial paralysis may provide advantages of both neural sources. However, quantitative functional outcome reports with a larger number of patients are lacking in the literature. Here we describe our 8-year experience with this surgical technique.

METHODS

Twenty patients that presented with a complete facial paralysis (duration <12 months) received dual reinnervation with CFNG and MNT. The functional outcome of the procedure was evaluated with the physician-graded outcome metric eFACE. The objective artificial intelligence-driven software Emotrics and FaceReader were used for oral commissure measurements and emotional expression assessment, respectively.

RESULTS

The mean follow-up was 31.75±23.32 months. In the eFACE score, the nasolabial fold depth and oral commissure at rest improved significantly (p<0.05) towards a more balanced state after the surgery. Postoperatively, there was a significant decrease in oral commissure asymmetry while smiling (19.22±6.1mm to 12.19±7.52mm). For the emotionality expression, the median intensity score of happiness, as measured by the FaceReader software, increased significantly while smiling (0.28, IQR 0.13-0.64). In 5 (25%) patients, a secondary static midface suspension with fascia lata strip had to be performed due to an unsatisfactory resting symmetry. Older patients and patients with greater preoperative resting asymmetry were more likely to receive static midface suspension.

CONCLUSIONS

Our results suggest that the combination of MNT and CFNG for reinnervation of facial paralysis provides good voluntary motion and may lessen the use of static midface suspension in the majority of patients.

Dermatofibrosarcoma protuberans of the scalp: Surgical management in a multicentric series of 11 cases and systematic review of the literature

BACKGROUND

Dermatofibrosarcoma protuberans is a rare, slow-growing soft-tissue malignancy originating in the dermis that is characterized by an infiltrating growth pattern with a marked tendency of local recurrence. Complete surgical resection with pathological margin clearance must be achieved to reduce the risk of tumor recurrence. Resulting defects often require extensive reconstructive procedures. Dermatofibrosarcoma protuberans of the scalp poses particular challenges owing to the proximity to the face and brain. This study aims to evaluate treatment options and proposes an algorithm for management of scalp dermatofibrosarcoma protuberans based on a multicentric case series and systematic review of the literature.

METHODS

A retrospective multicentric chart analysis of 11 patients with scalp dermatofibrosarcoma protuberans who presented within the last 20 years was performed regarding demographic data, pathological tumor characteristics, and surgical management (resection and reconstruction). Additionally, a further 42 patients (44 cases) were identified through a systematic Preferred Reporting Systems for Systematic Reviews and Meta-Analysis-based review of the literature searching the Medline and Embase databases.

RESULTS

In total, 30 cases were classified as primary and 20 cases as recurring scalp dermatofibrosarcoma protuberans (data from 5 cases were missing). The median tumor size was 24 cm2 (interquartile range 7.8-64), and the median defect size was 55.8 cm2 (interquartile range 48-112). Recurring scalp dermatofibrosarcoma protuberans was more often associated with invasion of deeper layers and required more extensive tumor resection to achieve negative margins. Within the subgroup that was managed with peripheral and deep en face margin assessment, no recurrence was observed. Most patients required local (41. 8%) or free flap (27.8%) reconstruction after dermatofibrosarcoma protuberans resection.

CONCLUSION

Whenever possible, peripheral and deep en face margin assessment-based techniques should be preferred for resection of scalp dermatofibrosarcoma protuberans because they provide superior oncological safety while preserving uninvolved tissue. Patients with locally advanced and recurring scalp dermatofibrosarcoma protuberans often require multidisciplinary treatment including neurosurgery, radiotherapy, and microvascular reconstructive surgery and should be referred to a specialized center.

Correlation between facial vascularized composite allotransplantation rejection and laboratory markers: Insights from a retrospective study of eight patients

BACKGROUND

The field of facial vascularized composite allotransplantation (fVCA) is still new and a limited number of patients have undergone the procedure. This has led to a lack of understanding about the impact of fVCA rejection on standard laboratory markers (e.g., CBC, BMP, CRP) for the acute management of these patients. It is not clear if rejection elicits a systemic inflammatory response that influences common inflammatory markers such as WBC and CRP. A comprehensive understanding of changes in these markers could help in the management of fVCA patients in the acute setting.

METHODS

The medical records of 8 fVCA patients with a total of 9 transplants were reviewed retrospectively, and data on standard laboratory values (CBC, BMP, LFTs, CRP) and vital signs were extracted. To examine the relationship between laboratory values and rejection status, linear mixed models were used to analyze the data, taking into account their longitudinal nature (repeated measures).

RESULTS

A statistically significant relationship was found between the Banff grade of rejection and the relative number of basophils in the patient's blood during rejection (p = 0.005). In addition, in patients with clinical signs of rejection (e.g., facial erythema, edema) and skin biopsy showing Banff ≥ II, CRP was found to be significantly elevated (p = 0.03). The WBC count remained stable during rejection, and the relative number of neutrophils was lower at the time of rejection, indicating possible consumption at the site of rejection.

CONCLUSION

During fVCA rejection, most standard laboratory parameters and vital signs appear to be stable. However, the levels of CRP and basophils were elevated during rejection, while the neutrophil count was lower. Leukocytosis can likely be used as a marker of microbial infection in fVCA patients, as WBC does not seem to increase at the time of allograft rejection.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgery (DGPRÄC) and Research Funding Report 2021/2022]

BACKGROUND

Research is an integral part of academic medicine. In plastic surgery, it sets the course for innovations in the specialty. The purpose of this study is to present the research performance of plastic surgeons in Germany for the period 2021/2022 and to compare it with previous periods.

MATERIALS AND METHODS

The directors of plastic surgical academic institutions reported all requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was gathered within an established online database. In addition, the DFG´s public database GEPRIS was screened for plastic surgical research grants. Data was also collected regarding research infrastructure and organization at the participating centers.

RESULTS

105 applications were reported to 54 different funding agencies from 20 plastic surgery centers. 37 funding applications were submitted to the major public funding agencies DFG, BMBF, BMWi, BMG, BMVg, G-BA and EU. Of these, 59,5% (22/37) were DFG, 13,5% (5/37) each BMBF and EU, 5,4% (2/37) BMWi, and 2,7% (1/37) each BMG, BMVg, and G-BA applications. The average funding volume of these proposals was 401,515 euros. Approved DFG proposals were most frequently assigned to the review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery (n=10/16, 62,5%). Over time, the research registry shows an increase in the number of proposals in general and those granted. 70,0% (14/20) of participating sites had their own experimental research laboratory, while only 40,0% (8/20) had their own clinical trial center.

CONCLUSION

The 2021/2022 Research Funding Report once again highlights the impressive research accomplishments of the plastic surgery community.

Multiparametric magnetic resonance imaging for radiation therapy response monitoring in soft tissue sarcomas: a histology and MRI co-registration algorithm

Rationale: To establish a spatially exact co-registration procedure between in vivo multiparametric magnetic resonance imaging (mpMRI) and (immuno)histopathology of soft tissue sarcomas (STS) to identify imaging parameters that reflect radiation therapy response of STS. Methods: The mpMRI-Protocol included diffusion-weighted (DWI), intravoxel-incoherent motion (IVIM), and dynamic contrast-enhancing (DCE) imaging. The resection specimen was embedded in 6.5% agarose after initial fixation in formalin. To ensure identical alignment of histopathological sectioning and in vivo imaging, an ex vivo MRI scan of the specimen was rigidly co-registered with the in vivo mpMRI. The deviating angulation of the specimen to the in vivo location of the tumor was determined. The agarose block was trimmed accordingly. A second ex vivo MRI in a dedicated localizer with a 4 mm grid was performed, which was matched to a custom-built sectioning machine. Microtomy sections were stained with hematoxylin and eosin. Immunohistochemical staining was performed with anti-ALDH1A1 antibodies as a radioresistance and anti-MIB1 antibodies as a proliferation marker. Fusion of the digitized microtomy sections with the in vivo mpMRI was accomplished through nonrigid co-registration to the in vivo mpMRI. Co-registration accuracy was qualitatively assessed by visual assessment and quantitatively evaluated by computing target registration errors (TRE). Results: The study sample comprised nine tumor sections from three STS patients. Visual assessment after nonrigid co-registration showed a strong morphological correlation of the histopathological specimens with ex vivo MRI and in vivo mpMRI after neoadjuvant radiation therapy. Quantitative assessment of the co-registration procedure using TRE analysis of different pairs of pathology and MRI sections revealed highly accurate structural alignment, with a total median TRE of 2.25 mm (histology - ex vivo MRI), 2.22 mm (histology - in vivo mpMRI), and 2.02 mm (ex vivo MRI - in vivo mpMRI). There was no significant difference between TREs of the different pairs of sections or caudal, middle, and cranial tumor parts, respectively. Conclusion: Our initial results show a promising approach to obtaining accurate co-registration between histopathology and in vivo MRI for STS. In a larger cohort of patients, the method established here will enable the prospective identification and validation of in vivo imaging biomarkers for radiation therapy response prediction and monitoring in STS patients via precise molecular and cellular correlation.

A novel phosphocholine-mimetic inhibits a pro-inflammatory conformational change in C-reactive protein

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.

C-reactive protein, immunothrombosis and venous thromboembolism

C-reactive protein (CRP) is a member of the highly conserved pentraxin superfamily of proteins and is often used in clinical practice as a marker of infection and inflammation. There is now increasing evidence that CRP is not only a marker of inflammation, but also that destabilized isoforms of CRP possess pro-inflammatory and pro-thrombotic properties. CRP circulates as a functionally inert pentameric form (pCRP), which relaxes its conformation to pCRP* after binding to phosphocholine-enriched membranes and then dissociates to monomeric CRP (mCRP). with the latter two being destabilized isoforms possessing highly pro-inflammatory features. pCRP* and mCRP have significant biological effects in regulating many of the aspects central to pathogenesis of atherothrombosis and venous thromboembolism (VTE), by directly activating platelets and triggering the classical complement pathway. Importantly, it is now well appreciated that VTE is a consequence of thromboinflammation. Accordingly, acute VTE is known to be associated with classical inflammatory responses and elevations of CRP, and indeed VTE risk is elevated in conditions associated with inflammation, such as inflammatory bowel disease, COVID-19 and sepsis. Although the clinical data regarding the utility of CRP as a biomarker in predicting VTE remains modest, and in some cases conflicting, the clinical utility of CRP appears to be improved in subsets of the population such as in predicting VTE recurrence, in cancer-associated thrombosis and in those with COVID-19. Therefore, given the known biological function of CRP in amplifying inflammation and tissue damage, this raises the prospect that CRP may play a role in promoting VTE formation in the context of concurrent inflammation. However, further investigation is required to unravel whether CRP plays a direct role in the pathogenesis of VTE, the utility of which will be in developing novel prophylactic or therapeutic strategies to target thromboinflammation.

Individualized Mini-Panel Sequencing of ctDNA Allows Tumor Monitoring in Complex Karyotype Sarcomas

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.

Autologous free tissue transfer in paediatric patient with a univentricular heart

We report on the case of a 30-month-old boy who developed severe deep cervical necrosis after bypass surgery for total cavopulmonary connection, followed by low-cardiac output and extracorporeal life support. As several bedside debridements failed to result in sufficient wound healing, a 2-stage necrectomy followed by autologous reconstruction with a free anterolateral thigh-flap was required. Due to impaired circulation, postoperative flap monitoring was extremely difficult. To ensure flap perfusion, mean arterial pressure had to be raised by catecholamines over 7 days.

Transitional changes in the structure of C-reactive protein create highly pro-inflammatory molecules: Therapeutic implications for cardiovascular diseases

C-reactive protein (CRP) is the prototypic acute-phase reactant that has long been recognized almost exclusively as a marker of inflammation and predictor of cardiovascular risk. However, accumulating evidence indicates that CRP is also a direct pathogenic pro-inflammatory mediator in atherosclerosis and cardiovascular diseases. The 'CRP system' consists of at least two protein conformations with distinct pathophysiological functions. The binding of the native, pentameric CRP (pCRP) to activated cell membranes leads to a conformational change resulting in two highly pro-inflammatory isoforms, pCRP* and monomeric CRP (mCRP). The deposition of these pro-inflammatory isoforms has been shown to aggravate the localized tissue injury in a broad range of pathological conditions including atherosclerosis and thrombosis, myocardial infarction, and stroke. Here, we review recent findings on how these structural changes contribute to the inflammatory response and discuss the transitional changes in the structure of CRP as a novel therapeutic target in cardiovascular diseases and overshooting inflammation.

Oncological Safety and Recurrence in the Surgical Treatment of Atypical Fibroxanthoma and Pleomorphic Dermal Sarcoma of the Scalp

Simple Summary

Atypical fibroxanthoma and pleomorphic dermal sarcoma represent two tumors on the spectrum of a rare dermal sarcoma entity. Close clinical presentation and nearly identical histologic features but distinct prognoses make proper treatment strategies challenging. We performed a retrospective analysis of 32 patients with AFX or PDS in the scalp to provide guidance regarding the extent of radical excision to achieve stable oncological outcomes and whether radical tumor resection on the scalps required complex soft-tissue reconstruction. Compared to AFX, PDS shows a more aggressive growth pattern with frequent satellite metastases and distant metastases. These require extensive resections for local control to achieve long-term remission in most PDS patients. Despite the limited elasticity of the scalp, plastic reconstructive procedures can obtain reliable soft tissue reconstruction, even for complete scalp defects. Due to their rarity, managing these tumors requires an interdisciplinary setting in a specialized sarcoma center.

Abstract

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.

Age-related outcome of facial reanimation surgery using cross face nerve graft and gracilis free functional muscle transfer-A retrospective cohort study

BACKGROUND

Free functional muscle transfer has become the criterion standard for the treatment of long-standing flaccid facial paralysis. Clinical experience suggests that a two-stage approach using a cross-face nerve graft (CFNG) as a donor nerve for free functional muscle transfers (FFMT) is less successful in older patients when compared to the pediatric population. However, clear data and scientific evidence are still rare. This study examines the age-related outcome of CFNG-driven FFMT.

METHODS

Twenty-eight patients with a mean age of 20.73 years (ranging 5-51 years) who received two-stage facial reanimation with CFNG-driven gracilis FFMT at our institution from 1998 to 2019 were included. The ipsilateral sural nerve was used as CFNG. After 12 months, the ipsilateral gracilis muscle was used as FFMT. Patients were distributed equally into three cohorts according to their age. We assessed facial symmetry before and after facial reanimation measuring the angle between the interpupillary and the intermodiolar line (pupillo-modiolar angle). Additionally, the commissure height was measured using the Emotrics software.

RESULTS

The mean follow-up of the pediatric, young adults and the middle-aged cohort was 29.5 ± 7.3, 24.9 ± 6.3, and 25.5 ± 12.4 months, respectively. One patient suffered flap loss due to flap ischemia. Four patients suffered insufficient innervation of the FFMT. Otherwise no major complication occurred. The likelihood of successful innervation of the FFMT was significantly higher in patients younger than 31 years (100% vs. 50%; p = .003). Smiling facial symmetry (pupillo-modiolar angle) significantly improved in the pediatric cohort (5-16 years; 8.68° ± 0.69° to 1.48° ± 0.67°; p < .001) and the young adults' cohort (17-30 years; 11.55° ± 1.95° to 4.62° ± 1.08°; p = .005), but improved only slightly in the middle-aged cohort (31-51 years; 11.77° ± 1.16° to 9.4° ± 1.8° p = .27). The postoperative smiling symmetry showed a significant correlation with increasing age (r = .62, p < .001). The smiling commissure height deviation significantly improved in the pediatric cohort (5-16 years; 6.5-2.3 mm; p = .006) and the postoperative result was significantly better than the middle-aged group (31-51 years; 2.3 vs. 7.5 mm; p = .02).

CONCLUSIONS

The outcome of CFNG-driven gracilis FFMT is age-related. Static as well as dynamic facial symmetry after two-stage facial reanimation was best in the pediatric and young adult population. For older patients, other approaches like the nerve-to-masseter-driven FFMT should be considered.

Newly identified axon types of the facial nerve unveil supplemental neural pathways in the innervation of the face

INTRODUCTION

Neuromuscular control of the facial expressions is provided exclusively via the facial nerve. Facial muscles are amongst the most finely tuned effectors in the human motor system, which coordinate facial expressions. In lower vertebrates, the extracranial facial nerve is a mixed nerve, while in mammals it is believed to be a pure motor nerve. However, this established notion does not agree with several clinical signs in health and disease.

OBJECTIVES

To elucidate the facial nerve contribution to the facial muscles by investigating axonal composition of the human facial nerve. To reveal new innervation pathways of other axon types of the motor facial nerve.

METHODS

Different axon types were distinguished using specific molecular markers (NF, ChAT, CGRP and TH). To elucidate the functional role of axon types of the facial nerve, we used selective elimination of other neuronal support from the trigeminal nerve. We used retrograde neuronal tracing, three-dimensional imaging of the facial muscles, and high-fidelity neurophysiological tests in animal model.

RESULTS

The human facial nerve revealed a mixed population of only 85% motor axons. Rodent samples revealed a fiber composition of motor, afferents and, surprisingly, sympathetic axons. We confirmed the axon types by tracing the originating neurons in the CNS. The sympathetic fibers of the facial nerve terminated in facial muscles suggesting autonomic innervation. The afferent fibers originated in the facial skin, confirming the afferent signal conduction via the facial nerve.

CONCLUSION

These findings reveal new innervation pathways via the facial nerve, support the sympathetic etiology of hemifacial spasm and elucidate clinical phenomena in facial nerve regeneration.

Genotyping of Circulating Free DNA Enables Monitoring of Tumor Dynamics in Synovial Sarcomas

Simple Summary

Synovial sarcomas (SS) are rare soft tissue tumors of mesenchymal origin. Following resection of the primary tumor, about one third to half of the patients suffer from recurrence. Detection of local and distant recurrence during follow-up is commonly accomplished by imaging. There are no biomarkers available for routine diagnostics. We employ a highly sensitive targeted next-generation sequencing approach to monitor tumor dynamics by genotyping of circulating free DNA (cfDNA) in SS patients. cfDNA which harbors tumor-specific mutations (circulating tumor-DNA; ctDNA) correlated with the presence of viable tumor tissue. This enables timely and non-invasive detection of tumor recurrence and monitoring of treatment response independent of the anatomic location.

Abstract

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.

Pharmacokinetic study of the novel phosphocholine derivative 3-dibutylaminopropylphosphonic acid by LC-MS coupling

CRP is an important mediator of the inflammatory response. Pro-inflammatory CRP effects are mediated by pCRP* and mCRP, dissociation products of the native pCRP. The concentration of pCRP during inflammation may rise up to concentrations 1000-fold from baseline. By prevention of the conformational change from pCRP to pCRP*, pro-inflammatory immune responses can be inhibited and local tissue damage reduced. 3-(Dibutylamino)propylphosphonic acid (C10m) is a new substance that can suppress ischemic-reperfusion injury by targeting CRP in the complement cascade. It hampers dissociation of pCRP into its monomers, thus preventing exacerbation of tissue inflammation subsequent to reperfusion injury. In this study, the pharmacokinetics and metabolism of the new drug candidate C10m was investigated. A sensitive and selective method for detection of C10m and its metabolites from plasma and urine was developed with LC-MS and LC-MS/MS coupling. The LLOQ is at 0.1 µg mL^-1 and recovery at 87.4% ± 2.8%. Accuracy and precision were within 15% coefficient of variation and nominal concentrations, respectively. Concentration time profile after i.v. bolus injection of C10m was analyzed by LC-MS/MS. Bioavailability has shown to be below 30%. Most likely due to the compounds' very polar chemical properties, no phase-I or phase-II metabolism could be observed. Absence of phase-I metabolism was cross-checked by performing microsomal incubations. Our study revealed that C10m is rapidly eliminated via urine excretion and that half-times appear to be increased with coadministration of the target pCRP.

Genetic Deficiency of TRAF5 Promotes Adipose Tissue Inflammation and Aggravates Diet-Induced Obesity in Mice

Objective: The accumulation of inflammatory leukocytes is a prerequisite of adipose tissue inflammation during cardiometabolic disease. We previously reported that a genetic deficiency of the intracellular signaling adaptor TRAF5 (TNF [tumor necrosis factor] receptor-associated factor 5) accelerates atherosclerosis in mice by increasing inflammatory cell recruitment. Here, we tested the hypothesis that an impairment of TRAF5 signaling modulates adipose tissue inflammation and its metabolic complications in a model of diet-induced obesity in mice. Approach and Results: To induce diet-induced obesity and adipose tissue inflammation, wild-type or Traf5-/- mice consumed a high-fat diet for 18 weeks. Traf5-/- mice showed an increased weight gain, impaired insulin tolerance, and increased fasting blood glucose. Weight of livers and peripheral fat pads was increased in Traf5-/- mice, whereas lean tissue weight and growth were not affected. Flow cytometry of the stromal vascular fraction of visceral adipose tissue from Traf5-/- mice revealed an increase in cytotoxic T cells, CD11c+ macrophages, and increased gene expression of proinflammatory cytokines and chemokines. At the level of cell types, expression of TNF[alpha], MIP (macrophage inflammatory protein)-1[alpha], MCP (monocyte chemoattractant protein)-1, and RANTES (regulated on activation, normal T-cell expressed and secreted) was significantly upregulated in Traf5-deficient adipocytes but not in Traf5-deficient leukocytes from visceral adipose tissue. Finally, Traf5 expression was lower in adipocytes from obese patients and mice and recovered in adipose tissue of obese patients one year after bariatric surgery. Conclusions: We show that a genetic deficiency of TRAF5 in mice aggravates diet-induced obesity and its metabolic derangements by a proinflammatory response in adipocytes. Our data indicate that TRAF5 may promote anti-inflammatory and obesity-preventing signaling events in adipose tissue.

Evaluation of the Suprafascial Thin ALT Flap in Foot and Ankle Reconstruction

BACKGROUND

 Distal lower extremity reconstruction can be challenging in terms of flap design. Bulky flaps result in limited mobility accompanied with the need of customized footwear. Raising the ALT-flap in a superficial fascial plane (thin ALT-flap) can be beneficial. This study evaluates thin ALT-flaps for lower distal extremity reconstruction.

METHODS

 In a retrospective study, patients that underwent microvascular extremity reconstruction at the level of the ankle and dorsal foot at the University of Freiburg from 2008-2018 were reviewed.

RESULTS

 95 patients could be included in the study (35 perforator flaps, 8 fascia flaps and 54 muscle flaps).Among the perforator flaps, 21 ALT-flaps were elevated conventionally and 14 in the superficial fascial plane (thin ALT-flap). Among the conventional ALT-flaps, there was one flap loss (5%) and one successful revision (5%). 5(24%) flaps received secondary thinning. 57%(n = 12) were able to wear conventional footwear. There were 2(15%) successful revisions of thin ALT-flaps. 100% of thin ALT-flaps survived and 85%(n = 11) of the patients wore ordinary footwear after defect coverage.Among fascial flaps, 50%(n = 4) had to be revised with 2(25%) complete and 1 (13%) partial flap loss. All patients achieved mobility in ordinary shoes (n = 8).In muscle flaps, there were 7(13%) revisions and 5(9%) flap losses. 5(9%) flaps received secondary thinning. Only 33%(n = 18) were mobile in ordinary footwear.

CONCLUSION

 The thin ALT-flap is a save one-stage evolution for lower distal extremity reconstruction with a favorable flap survival rate. Compared with conventional ALT-flaps it might be beneficial in reducing the need for expensive custom fitted shoes and secondary thinning procedures.

Artificial Intelligence-Driven Video Analysis for Novel Outcome Measures After Smile Reanimation Surgery

Background: Since facial paralysis is a dynamic condition, the analysis of still photographs is not sufficient for measurement of facial reanimation outcomes. This study aimed at evaluating an artificial intelligence (AI)-driven software as a novel video assessment tool for smile reanimation surgery and at comparing it with the Terzis score. Methods: Patients with facial paralysis undergoing smile reanimation surgery between January 2008 and April 2020 were eligible for this retrospective study. Inclusion criteria were at least 6 months of follow-up and availability of both pre- and post-operative video documentation. The software output was given as intensity score (IS) values between 0 and 1, representing emotions/action units (AUs) that are absent or fully present, respectively. Results: During the study period, 240 patients underwent facial reanimation surgery, of whom 63 patients met the inclusion criteria. Postoperatively, the median IS of the happiness emotion and lip corner puller AU increased significantly (p < 0.001). There was a positive correlation of Terzis score with the IS of happiness emotion (r = 0.8) and lip corner puller AU (r = 0.74). Conclusions: The novel AI-driven video analysis is strongly correlated with the Terzis score and shows promise for objective functional outcome evaluation after smile reanimation surgery.

An Unbiased Flow Cytometry-Based Approach to Assess Subset-Specific Circulating Monocyte Activation and Cytokine Profile in Whole Blood

Monocytes are the third most frequent type of leukocytes in humans, linking innate and adaptive immunity and are critical drivers in many inflammatory diseases. Based on the differential expression of surface antigens, three monocytic subpopulations have been suggested in humans and two in rats with varying inflammatory and phenotype characteristics. Potential intervention strategies that aim to manipulate these cells require an in-depth understanding of monocyte behavior under different conditions. However, monocytes are highly sensitive to their specific activation state and expression of surface markers, which can change during cell isolation and purification. Thus, there is an urgent need for an unbiased functional analysis of activation in monocyte subtypes, which is not affected by the isolation procedure. Here, we present a flow cytometry-based protocol for evaluating subset-specific activation and cytokine expression of circulating blood monocytes both in humans and rats using small whole blood samples (50 - 100 μL). In contrast to previously described monocyte isolation and flow cytometry visualization methods, the presented approach virtually leaves monocyte subsets in a resting state or fixes them in their current state and allows for an unbiased functional endpoint analysis without prior cell isolation. This protocol is a comprehensive tool for studying differential monocyte regulation in the inflammatory and allogeneic immune response in vitro and vivo.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) and Research Funding Report 2019/2020]

BACKGROUND

 Since 2015/16 the DGPRÄC collects, evaluates and publishes the research activities of academic sections, departments and clinics for plastic surgery at university hospitals in Germany, in order to raise the awareness of plastic surgical research performance.

MATERIALS AND METHODS

 The directors of plastic surgical academic institutions were contacted via the DGPRÄC and asked to report any requested/approved and rejected research applications to public, non-public and industrial funding organizations. Data was collected in our previously established online database: https://docs.google.com/forms/d/e/1FAIpQLSe6F5xmTyw-k7VKJx_2jkPA4LBXsA0sgBGMrC3rx_4bHj6uzQ/viewform?usp=sf_link. In addition, applications were identified via the DFG's public database GEPRIS.

RESULTS

 A total of 41 funding applications to the public funding institutes DFG, BMBF, BMWi, BMG and EU were identified. 75.6 % (31/41) of the applications had already been approved at the time of data collection, of which 77.4 % (24/31) were DFG, 9.7 % (3/31) were BMWi, 6.5 % (2/31) were EU and 3.2 % (1/31) were BMBF or BMG applications. The average funding amounted to 358 301 Euro. In 50.0 % (12/24) of the cases, the approved DFG proposals were assigned to the subject review board 205-27 Orthopedics, Trauma Surgery, Reconstructive Surgery.

CONCLUSION

 The continuous publication of plastic surgical research funding reports submitted by the convention of university plastic surgeons of the DGPRÄC portraits the excellent, collaborative research activity in the field of plastic surgery.

[Economic factors in microsurgery - Report of the consensus workshop of the German-Speaking Society for Microsurgery of Peripheral Nerves and Vessels - (DAM)]

In addition to outcome assessments, cost effectiveness of surgical treatments becomes increasingly important. Both, insurance companies and hospital administrations aim for short and efficient procedures to reduce costs.Microsurgical procedures are often surpassing traditional treatment options in terms of function and aesthetics. However, they are more expensive as they require a high level of surgical expertise, more theatre capacity and longer inpatient treatment. Adequate reimbursement is mandatory, if we want to continuously perform these procedures with the best possible quality and outcome. To cover the case-related expenses of each specialty, multidisciplinary procedures require appropriate distribution of reimbursements to each department.The main diagnosis as well as all complications and relevant comorbidities should be documented to obtain the correct DRG. The additional financial benefit of a microsurgical procedure in a multidisciplinary case can be calculated by specifying the procedural increment in pay. Therefore, a fair distribution of revenues to each participating department should be performed. Different models exist, which lead to a benefit in compensation for all departments. Unfortunately, distribution of resources is still insufficiently managed in many hospitals, which hampers high quality multidisciplinary microsurgical procedures. Still, picking the best possible procedure for our patients, independently of financial incentives, is of utmost importance.

Reconstruction of Perineal Defects: A Comparison of the Myocutaneous Gracilis and the Gluteal Fold Flap in Interdisciplinary Anorectal Tumor Resection

Introduction: Resection of anorectal malignancies may result in extensive perineal/pelvic defects that require an interdisciplinary surgical approach involving reconstructive surgery. The myocutaneous gracilis flap (MGF) and the gluteal fold flap (GFF) are common options for defect coverage in this area. Here we report our experience with the MGF/GFF and compare the outcome regarding clinical key parameters.

Methods: In a retrospective chart review, we collected data from the Department of Plastic Surgery of the University of Freiburg from December 2008–18 focusing on epidemiological, oncological, and therapy-related data including comorbidities (ASA Classification) and peri-/postoperative complications (Clavien-Dindo-System).

Results: Twenty-nine patients were included with a mean follow-up of 17 months. Of the cases, 19 (65.5%) presented with recurrent disease, 21 (72.4%) received radiochemotherapy preoperatively, 2 (6.9%) received chemotherapy alone. Microscopic tumor free margins were achieved in 25 cases (86.2%). 17 patients (7 men, 10 women, rectal adenocarcinoma n = 11; anal squamous cell carcinoma n = 6; mean age 58.5 ± 10.68, mean BMI 23.1, mean ASA score 2.8) received a MGF (unilateral n = 10; bilateral n = 7). Twelve patients (7 men, 5 women, rectal adenocarcinoma n = 7; anal squamous cell carcinoma n = 4, proctodeal gland carcinoma n = 1, mean age 66.2 ± 9.2, mean BMI 23.6, mean ASA score 2.6) received coverage with a GFF (unilateral n = 4; bilateral n = 8). Mean operation time of coverage was 105 ± 9 min for unilateral and 163 ± 11 for bilateral MGFs, 70 ± 13 min for unilateral and 107 ± 14 for bilateral GFFs. Complications affected 62%. There was no significant difference in the complication rate between the MGF- and GFF-group. Complications were mainly wound healing disorders that did not extend the hospital stay. No flap loss and no complication that lead to long-lasting disability was documented (both groups). Pain-free sitting took more time in the GFF-group due to the location of the donor site.

Conclusion: MG-flaps and GF-flaps prove to be reliable and robust techniques for perineal/pelvic reconstruction. Though flap elevation is significantly faster for GF-flaps, preoperative planning and intraoperative Doppler confirmation are advisable. With comparable complication rates, we suggest a decision-making based on distribution of adipose tissue for dead space obliteration, intraoperative patient positioning, and perforator vessel quality/distribution.

C-Reactive Protein and Its Structural Isoforms: An Evolutionary Conserved Marker and Central Player in Inflammatory Diseases and Beyond

C-reactive protein (CRP) is an evolutionary highly conserved member of the pentraxin superfamily of proteins. CRP is widely used as a marker of inflammation, infection and for risk stratification of cardiovascular events. However, there is now a large body of evidence, that continues to evolve, detailing that CRP directly mediates inflammatory reactions and the innate immune response in the context of localised tissue injury. These data support the concept that the pentameric conformation of CRP dissociates into pro-inflammatory CRP isoforms termed pCRP* and monomeric CRP. These pro-inflammatory CRP isoforms undergo conformational changes that facilitate complement binding and immune cell activation and therefore demonstrate the ability to trigger complement activation, activate platelets, monocytes and endothelial cells. The dissociation of pCRP occurs on the surface of necrotic, apoptotic, and ischaemic 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. Therefore, the deposition and localisation of these pro-inflammatory isoforms of CRP have been demonstrated to amplify inflammation and tissue damage in a broad range of clinical conditions including ischaemia/reperfusion injury, Alzheimer's disease, age-related macular degeneration and immune thrombocytopaenia. Given the potentially broad relevance of CRP to disease pathology, the development of inhibitors of CRP remains an area of active investigation, which may pave the way for novel therapeutics for a diverse range of inflammatory diseases.

Efficacy and Safety of Microsurgery in Interdisciplinary Treatment of Sarcoma Affecting the Bone

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.

[The "safe" flap - Preoperative perforator-mapping and intraoperative perfusion assessment to reduce flap-associated morbidity - Consensus statement of the German Speaking Working Group for Microsurgery of the Peripheral Nerves and Vessels]

Reconstructive microsurgery using free and pedicled flaps has become a reliable method with a high success rate. Preoperative perforator mapping and intraoperative assessment of perfusion might further reduce flap-associated morbidity.There are various techniques for perforator mapping and perfusion measurement, but no guidelines regarding their use. Therefore, an expert panel at the 40th Annual Meeting of the German-Speaking Working Group for Microsurgery of the Peripheral Nerves and Vessels (DAM) discussed and critically reviewed the current literature. The consensus statement represents the expert opinion based on the available literature and provides recommendations regarding the use of preoperative perforator mapping and intraoperative perfusion measurement.

Lysophosphatidylcholine is a Major Component of Platelet Microvesicles Promoting Platelet Activation and Reporting Atherosclerotic Plaque Instability

BACKGROUND

 Microvesicles (MVs) are small cell-derived vesicles, which are mainly released by activated cells. They are part of a communication network delivering biomolecules, for example, inflammatory molecules, via the blood circulation to remote cells in the body. Platelet-derived MVs are known to induce vascular inflammation. Research on the mediators and mechanisms of their inflammatory effects has attracted major interest. We hypothesize that specific lipids are the mediators of vascular inflammation caused by platelet-derived MVs.

METHODS AND RESULTS

 Liquid chromatography electrospray ionization-tandem mass spectrometry was used for lipid profiling of platelet-derived MVs. Lysophosphatidylcholine (LPC) was found to be a major component of platelet-derived MVs. Investigating the direct effects of LPC, we found that it induces platelet activation, spreading, migration and aggregation as well as formation of inflammatory platelet-monocyte aggregates. We show for the first time that platelets express the LPC receptor G2AR, which mediates LPC-induced platelet activation. In a mouse model of atherosclerotic plaque instability/rupture, circulating LPC was detected as a surrogate marker of plaque instability. These findings were confirmed by matrix-assisted laser desorption ionization imaging, which showed that the LPC concentration of human plaques was highest in vulnerable plaque regions.

CONCLUSION

 LPC is a major component of platelet-derived MVs and via its interaction with G2AR on platelets contributes to platelet activation, spreading, migration and aggregation and ultimately to vascular inflammation. Circulating LPC reports on atherosclerotic plaque instability in mice and is significantly increased in unstable areas of atherosclerotic plaques in both mice and humans, linking LPC to plaque instability.

Genotyping of circulating cell-free DNA enables noninvasive tumor detection in myxoid liposarcomas

Soft tissue sarcomas (STS) are rare tumors of mesenchymal origin. About 50% of patients with STS experience relapse and more than 30% will die within 10 years after diagnosis. In this study we investigated circulating free DNA (cfDNA) and tumor-specific genetic alterations therein (circulating tumor DNA, ctDNA) as diagnostic biomarkers. Plasma concentrations and fragmentation of cfDNA was analyzed with quantitative PCR. Patients with STS (n = 64) had significantly higher plasma concentrations and increased fragmentation of cfDNA when compared to patients in complete remission (n = 19) and healthy controls (n = 41) (p < 0.01 and p < 0.001). Due to overlapping values between patients with STS and controls, the sensitivity and specificity of these assays is limited. Sensitive assays to detect genomic alterations in cfDNA of synovial sarcomas (t(X;18)), myxoid liposarcomas (t(12;16) and TERT C228T promoter mutation) and well-differentiated/de-differentiated liposarcomas (MDM2 amplifications) were established. ctDNA was quantified in nine liposarcoma patients during the course of their treatment. Levels of breakpoint t(12;16) and TERT C228T ctDNA correlated with the clinical course and tumor burden in patients with myxoid liposarcomas (n = 4). ctDNA could detect minimal residual disease and tumor recurrence. In contrast, detection of MDM2 amplifications was not sensitive enough to detect tumors in patients with well-differentiated/de-differentiated liposarcomas (n = 5). Genotyping of cfDNA for tumor specific genetic alterations is a feasible and promising approach for monitoring tumor activity in patients with myxoid liposarcomas. Detection of ctDNA during follow-up examinations despite negative standard imaging studies might warrant more sensitive imaging (e.g. PET-CT) or closer follow-up intervals to timely localize and treat recurrences.

[Registry Research Funding of the German Society of Plastic, Reconstructive and Aesthetic Surgeons (DGPRÄC) and Research Funding Report 2017/2018]

INTRODUCTION

This report serves to publicize the research of academic institutions for Plastic Surgery within our society DGPRÄC in 2017/2018 and sequels the funding report of 2015/2016. Applications to public, non-public, or industrial funding organizations were evaluated. At the same time, this paper analyses the number of approved DFG applications in Plastic, Thoracic and Vascular Surgery in the GEPRIS system. Contrary to these specialties, Plastic Surgery is not classified as an independent speciality in the subject structure of the DFG review board which results in a lack of transparency concerning Plastic Surgery research work.

MATERIALS AND METHODS

Our previously established online database (https://docs.google.com/forms/d/1OaSnHyKTysawiI1ie7kfUxDf7nJP_RiTUJTsnb7Mq_E/edit) for reporting requested/ approved and rejected research applications to public, non-public and industrial funding organizations was continued and evaluated together with applications found in the DFG's public database GEPRIS.

RESULTS

Compared to the previous year's report, the number of approved applications from public research organizations (DFG, BMBF, BMWi, EU) was increased from 23 to 27. We identified 19 approved DFG applications from Plastic Surgery, as compared to 9 and 8 applications by Thoracic and Vascular Surgery, respectively.

SUMMARY

Taken together, this data emphasizes that our research is at least equal to that of other newly established surgical specialties within the framework of the DFG. Accordingly, we hope to provide further arguments for an adaptation of the DFG review boards subject structure to include Plastic Surgery as an independent specialty as it is for Vascular Surgery and Thoracic Surgery.

[Breast reconstruction with the free TRAM or DIEP flap – What is the current standard? Consensus Statement of the German Speaking Working Group for Microsurgery of the Peripheral Nerves and Vessels]

The most common donor-site for autologous breast reconstruction is the abdomen. Over the past several decades technical advances have resulted in the development of flaps that have been associated with a progressive decrease in abdominal wall morbidity. However, controversy exists related to the differences between muscle-sparing (MS)-TRAM and deep inferior epigastric perforator (DIEP) flaps. Hence, the question which approach should be considered standard of care remains unanswered. To address this question the current literature and published evidence was critically reviewed and discussed by an expert panel at the 39th Annual Meeting of the German-speaking Society for Micro surgery of the Peripheral Nerves and Vessels (DAM). Based on this discussion a consensus statement was developed that incorporates contemporary data regarding postoperative complication rate, donor site morbidity, as well as expert opinion regarding technical details in autologous breast reconstruction with free TRAM and DIEP flaps.

Pedicled and free flaps for intrathoracic fistula management

OBJECTIVES

Intrathoracic fistulae are among the potential sequelae of radiation therapy, empyema and abscess clearance and surgical tumour resections. Interdisciplinary plastic-reconstructive flap surgery is a helpful tool for the successful treatment of intrathoracic fistulae.

METHODS

From February 2006 to April 2016, 13 patients (3 females and 10 males) underwent flap surgery for bronchial (n = 5), tracheal (n = 2), oesophageal (n = 2), post-pneumonectomy bronchopleural fistula (n = 2), tracheo-oesophageal (n = 1), gastrobronchial (n = 1) and oesophagobronchial (n = 1) fistulae. Patient characteristics, identified pathogenic micro-organisms, treatment and decision criteria, long-term outcome and postoperative complications were evaluated by analysing patient charts and surgical reports.

RESULTS

The mean age of the 13 patients who underwent reconstructive surgery was 55.5 years (range: 42-66 years). The median follow-up time was 31.4 months (range: 2-96 months). American Society of Anaesthesiologists classification was II for 1 patient, III for 8 patients and IV for 4 patients. In total, 18 flaps were performed (7 latissimus dorsi pedicled flaps, 7 pectoralis major pedicled flaps, 2 rectus abdominis myocutaneous flaps, 1 free temporo-parietal fascia flap and 1 intercostal muscle flap). A second flap was indicated in 5 cases (38.5%) due to fistula recurrence; of these, 1 patient developed a bronchial fistula after successful reconstruction of a gastrobronchial fistula. Eight of the 13 patients (61.5%) were evaluated postoperatively at regular intervals for at least 1 year and showed no signs of fistula recurrence.

CONCLUSIONS

Our study showed that plastic-reconstructive flap surgery, although associated with significant morbidity and mortality, can be a life-saving tool for intrathoracic fistula reconstruction.

Clinical Trial Registration

DRKS00010447.

A Conformational Change in C-Reactive Protein Enhances Leukocyte Recruitment and Reactive Oxygen Species Generation in Ischemia/Reperfusion Injury

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.

Extracellular Vesicles: Packages Sent With Complement

Cells communicate with other cells in their microenvironment by transferring lipids, peptides, RNA, and sugars in extracellular vesicles (EVs), thereby also influencing recipient cell functions. Several studies indicate that these vesicles are involved in a variety of critical cellular processes including immune, metabolic, and coagulatory responses and are thereby associated with several inflammatory diseases. Furthermore, EVs also possess anti-inflammatory properties and contribute to immune regulation, thus encouraging an emerging interest in investigating and clarifying mechanistic links between EVs and innate immunity. Current studies indicate complex interactions of the complement system with EVs, with a dramatic influence on local and systemic inflammation. During inflammatory conditions with highly activated complement, including after severe tissue trauma and during sepsis, elevated numbers of EVs were found in the circulation of patients. There is increasing evidence that these shed vesicles contain key complement factors as well as complement regulators on their surface, affecting inflammation and the course of disease. Taken together, interaction of EVs regulates complement activity and contributes to the pro- and anti-inflammatory immune balance. However, the molecular mechanisms behind this interaction remain elusive and require further investigation. The aim of this review is to summarize the limited current knowledge on the crosstalk between complement and EVs. A further aspect is the clinical relevance of EVs with an emphasis on their capacity as potential therapeutic vehicles in the field of translational medicine.

Evaluation of the Implantable Doppler Probe for Free Flap Monitoring in Lower Limb Reconstruction

BACKGROUND

 Timely reexploration and reanastomoses can salvage failing free flaps. The use of the implantable Doppler probe provides direct evidence of vascular impairment of the microvascular anastomoses and allows for postoperative NPWT. The aim of this retrospective study was to compare the Doppler probe to conventional monitoring techniques for free flap monitoring in lower limb reconstruction and to identify risk factors for perfusion disturbance and reexploration.

METHODS

 All patients receiving free muscle flap reconstruction for lower limb soft tissue defects at our department from 2000 to 2013 were included, and all adverse events, timely detection of perfusion problems, and outcome of revision surgery were assessed by chart analysis.

RESULTS

 For lower limb reconstruction, 110 free muscle transfers were performed of which 41 muscle flaps were conventionally monitored and 69 flaps were monitored using the implantable Doppler probe. In 18 cases, the free muscle flaps needed revision because of perfusion disturbances. The salvage rate was 80% with monitoring by the implantable Doppler probe compared with 62.5% using conventional monitoring methods resulting in success rates of 95.7 and 92.7%, respectively.

CONCLUSION

 The use of the implantable Cook-Swartz Doppler probe represents a safe monitoring method for lower limb reconstruction, which allows for the additional use of NPWT. Higher salvage and revision success rates can be attributed to an earlier detection of perfusion impairment. However, a larger patient cohort is necessary to verify superiority over conventional postoperative monitoring.

Levels of activated platelet-derived microvesicles in patients with soft tissue sarcoma correlate with an increased risk of venous thromboembolism

Background

Microvesicles are small vesicles expressing specific antigens from their cells of origin. Elevated levels of microvesicles have been shown to be associated with coagulation disorders as well as with different types of malignancies. This study aims to evaluate a possible correlation of different microvesicle subpopulations with a positive history of venous thromboembolism (VTE) in patients with soft tissue sarcoma.

Methods

Annexin V - positive microvesicles, leukocyte (CD45-positive), platelet (CD61-positive), activated platelet (CD62P-, CD63-positive), endothelium-derived (CD62E-positive) and tissue-factor (CD142-positive) microvesicles were identified in the peripheral blood of patients with soft tissue sarcoma (n = 39) and healthy controls (n = 17) using fluorescence-activated cell sorting (FACS).

Results

Both the total amount of Annexin V-positive microvesicles and levels of endothelium-derived (CD62E-positive) microvesicles were shown to decrease significantly after tumor resection (n = 18, p = 0.0395 and p = 0.0109, respectively). Furthermore, the total amount of Annexin V – positive microvesicles as well as leukocyte (CD45-positive) and endothelium-derived (CD62E-positive) microvesicles were significantly higher in patients with grade 3 (G3) soft tissue sarcoma (n = 9) compared to healthy controls (n = 17) (p = 0.0304, p = 0.0254 and p = 0.0357, respectively). Moreover, patients with G3 soft tissue sarcoma (n = 9) presented higher levels of Annexin V-positive and endothelium-derived (CD62E-positive) microvesicles compared to patients with grade 2 (G2) soft tissue sarcoma (n = 8) (p = 0.0483 and p = 0.0045). Patients with grade 1 (G1) soft tissue sarcoma (n = 3) presented with significantly lower levels of platelet (CD61-positive) microvesicles than patients with G3 soft tissue sarcoma (n = 9) (p = 0.0150).

In patients with a positive history of VTE (n = 11), significantly higher levels of activated platelet (CD62P- and CD63-positive) microvesicles (p = 0.0078 and p = 0.0450, respectively) were found compared to patients without a history of VTE (n = 28).

Conclusion

We found significantly higher levels of Annexin V-positive and endothelium-derived (CD62E-positive) microvesicles to be circulating in the peripheral blood of patients with G3 soft tissue sarcoma compared to patients with G2 soft tissue sarcoma. Furthermore, we showed that high counts of activated platelet-derived microvesicles correlate with the occurrence of VTE. Thus, the detection of these microvesicles might be an interesting new tool for early diagnosis of soft tissue sarcoma patients with increased risk for VTE, possibly facilitating VTE prevention by earlier use of thromboprophylaxis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3515-y) contains supplementary material, which is available to authorized users.

Renal Denervation Reduces Monocyte Activation and Monocyte-Platelet Aggregate Formation: An Anti-Inflammatory Effect Relevant for Cardiovascular Risk

Overactivation of renal sympathetic nervous system and low-grade systemic inflammation are common features of hypertension. Renal denervation (RDN) reduces sympathetic activity in patients with resistant hypertension. However, its effect on systemic inflammation has not been examined. We prospectively investigated the effect of RDN on monocyte activation and inflammation in patients with uncontrolled hypertension scheduled for RDN. Ambulatory blood pressure, monocyte, and monocyte subset activation and inflammatory markers were assessed at baseline, 3 months, and 6 months after procedure in 42 patients. RDN significantly lowered blood pressure at 3 months (150.5±11.2/81.0±11.2 mm Hg to 144.7±11.8/77.9±11.0 mm Hg), which was sustained at 6 months (144.7±13.8/78.6±11.0 mm Hg). Activation status of monocytes significantly decreased at 3 months (P<0.01) and 6 months (P<0.01) after the procedure. In particular, classical monocyte activation was reduced at 6 months (P<0.05). Similarly, we observed a reduction of several inflammatory markers, including monocyte-platelet aggregates (3 months, P<0.01), plasma monocyte chemoattractant protein-1 levels (3 months, P<0.0001; 6 months, P<0.05), interleukin-1β (3 months, P<0.05; 6 months, P<0.05), tumor necrosis factor-α (3 months, P<0.01; 6 months, P<0.05), and interleukin-12 (3 months, P<0.01; 6 months, P<0.05). A positive correlation was observed between muscle sympathetic nerve activity and monocyte activation before and after the procedure. These results indicate that inhibition of sympathetic activity via RDN is associated with a reduction of monocyte activation and other inflammatory markers in hypertensive patients. These findings point to a direct interaction between the inflammatory and sympathetic nervous system, which is of central relevance for the understanding of beneficial cardiovascular effects of RDN.

Metabolic Response to XD14 Treatment in Human Breast Cancer Cell Line MCF-7

XD14 is a 4-acyl pyrrole derivative, which was discovered by a high-throughput virtual screening experiment. XD14 inhibits bromodomain and extra-terminal domain (BET) proteins (BRD2, BRD3, BRD4 and BRDT) and consequently suppresses cell proliferation. In this study, metabolic profiling reveals the molecular effects in the human breast cancer cell line MCF-7 (Michigan Cancer Foundation-7) treated by XD14. A three-day time series experiment with two concentrations of XD14 was performed. Gas chromatography-mass spectrometry (GC-MS) was applied for untargeted profiling of treated and non-treated MCF-7 cells. The gained data sets were evaluated by several statistical methods: analysis of variance (ANOVA), clustering analysis, principle component analysis (PCA), and partial least squares discriminant analysis (PLS-DA). Cell proliferation was strongly inhibited by treatment with 50 µM XD14. Samples could be discriminated by time and XD14 concentration using PLS-DA. From the 117 identified metabolites, 67 were significantly altered after XD14 treatment. These metabolites include amino acids, fatty acids, Krebs cycle and glycolysis intermediates, as well as compounds of purine and pyrimidine metabolism. This massive intervention in energy metabolism and the lack of available nucleotides could explain the decreased proliferation rate of the cancer cells.

Microsurgical reconstruction of oncological scalp defects in the elderly

The incidence of scalp tumors requiring radical excision increases with age. Free flap surgery is the standard reconstructive option for large defects; however, there is an ongoing uncertainty about its safety in the elderly. We conducted a review of data and report on 19 patients aged ≥75 years and 13 < 75 years. Data regarding patient demographics, types of tumors, surgery, size of defect, flaps used, and prevalence of complications were analyzed. The patients in the elderly group had more accompanying medical conditions and a higher ASA score. Squamous cell carcinoma was the predominant tumor in the elderly and sarcoma in the younger patients. The defect size was similar in both groups. The latissimus dorsi (LD) and the anterolateral thigh (ALT) flaps were flaps of first choice, with temporal vessels most commonly used for anastomosis. Surgery lasted longer in the younger patients. There was no difference in the duration of hospital stay. No significant correlation was found between age and the flap-related or medical complications. Revision surgery was more often required in the younger patients. We conclude that free flap surgery is safe and reliable in the elderly population. The LD and the ALT are the most commonly used flaps. Advanced age should not be considered a risk factor for free flap surgery in these patients.

Impact of increasing age on breast reduction surgery: A single centre analysis

BACKGROUND

Women with hypertrophic breasts suffer for physical and psychological reasons. Breast reduction surgery is a safe procedure that can effectively improve symptoms and quality of life. As most studies have been performed in younger women, little is known about complications and long-term patient satisfaction in elderly women.

PATIENTS AND METHODS

We analysed complication rates and patient satisfaction in women aged 60 years and older who underwent a bilateral reduction mammaplasty. Patient satisfaction was measured with a validated questionnaire (client satisfaction questionnaire (CSQ)-8). The results obtained were compared to those of a control group including women aged 35 years and younger.

RESULTS

Twenty-five women met the inclusion criteria in each group. The mean age in the elderly and young was 65.4 and 23.4 years, respectively. Older women had more comorbidities (35 vs. 9, p < 0.05). The average overall resection weight was 1684.4 g with slightly lower resection weights in younger women (1541 vs. 1828 g; p = 0.34). Eight women in the young group and 11 in the elderly developed minor complications (p = 0.56). Two women in the young group had major complications. Patient satisfaction was significantly higher in older women, with a mean score of 27.3 in the young and 30.3 in the elderly (maximum score of CSQ-8: 32, p < 0.05).

CONCLUSIONS

Age is not a contraindication for reduction mammaplasty. Breast reduction surgery is a safe procedure in elderly women and leads to even higher patient satisfaction. Level of evidence: IV.

Identification of a blood-borne miRNA signature of synovial sarcoma

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.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0424-z) contains supplementary material, which is available to authorized users.

Salvage procedures after failed facial reanimation surgery using the masseteric nerve as the motor nerve for free functional gracilis muscle transfer

IMPORTANCE

Free muscle transfer innervated by a cross-facial nerve graft represents the criterion standard for smile reconstruction in facial paralysis. If primary reconstruction fails, a second muscle transfer is usually needed. Herein, we investigated the possibility of avoiding a second free muscle transfer by in situ coaptation of the gracilis muscle to the masseteric nerve.

OBSERVATIONS

We report a series of 3 failed free muscle transfers for facial reanimation among 21 free flap transfers performed for facial reanimation between March 2008 and August 2013. To salvage the muscle, we performed coaptation of the neural pedicle from the cross-facial nerve graft to the masseteric nerve. This method allows for leaving the fixation sutures of the muscle at the oral commissure in place. All patients showed muscle contraction after 3 months and a smile with open mouth after 6 months. No significant difference in the range of commissure excursion was observed between the healthy and operated sides.

CONCLUSIONS AND RELEVANCE

Recoaptation of the neural pedicle from the cross-facial nerve graft to the masseteric nerve, leaving the muscle transplant in place, is a suitable salvage procedure after unsuccessful reconstruction with a cross-facial nerve graft, avoiding a second free muscle transfer.

LEVEL OF EVIDENCE

4.

The attractive lip: A photomorphometric analysis

BACKGROUND

Throughout literature, there are different parameters defining the ideal shape of the lip and lower third of the face. This study was conducted to clarify what it is that makes lips attractive - and whether there are gender-related differences of an attractive lip and lower third of the face.

PATIENTS AND METHODS

Pictures of the lip and chin region of 176 patients were photographed in a standardised way and evaluated by 250 voluntary judges through an internet presentation by means of an analogue Likert scaling system.

RESULTS

We found a significant higher ratio of upper vermillion height/mouth-nose distance in frontal-view images of attractive compared to unattractive female (p < 0.001) and male (p < 0.05) perioral regions. Furthermore, the ratio of upper vermillion height/chin-nose distance was significantly higher in attractive than in unattractive female (p < 0.005) and male (p < 0.05) lip and chin regions. The nasolabial angle was significantly sharper in attractive compared to unattractive female perioral regions (p < 0.001). Moreover, attractive female lip and chin regions showed a wider mentolabial angle compared to unattractive female lip and chin regions (p < 0.05). Comparing men and women, we found that attractive female perioral regions showed a higher ratio of lower vermillion height/chin-mouth distance (p < 0.05) and lower vermillion height/chin-nose distance than attractive male perioral regions (p < 0.05).

CONCLUSION

We were able to define certain parameters of the lip and lower third of the face that seem to add to the attractivity of female and male individuals and prove that there are gender-related differences in form and shape of an attractive lower third of the face.