Aesthetic Surgery Fellowship at Akademikliniken Stockholm: Survey among Graduates.

BACKGROUND: Aesthetic Surgery is one of the most competitive fields of plastic surgery. Although there is a certain demand for highly educated surgeons in this field, training in cosmetic procedures remains challenging. Akademikliniken Stockholm offers a highly appreciated fellowship program for aesthetic plastic surgeons and trained more than 200 surgeons from all over the world. OBJECTIVES: The aim of the present work was to provide insights into this fellowship program, analyze what graduates have learned and if this had implications on their further professional orientation. METHODS: Participants of the Akademikliniken fellowship program, who graduated between 10/2008 and 10/2018 (n = 66) were invited to take part in an online survey which included 30 questions about general demographics and about experience before, during and after the fellowship. RESULTS: Thirty-four graduates participated in the survey (52%). Twenty-four graduates (71%) had been already specialists in plastic surgery before commencing the fellowship program. Mean length of fellowship was 7 months (range 3-24months). Numbers of aesthetic procedures performed by the applicants significantly increased after the fellowship, and moreover, the scope of daily clinical practice shifted toward aesthetics in almost all applicants. CONCLUSIONS: A well-designed dedicated aesthetic surgery fellowship can improve the lack of training, aesthetic surgeons have during their residency. Graduates of our fellowship program reported great improvements in confidence in performing aesthetic procedures and a benefit for their future career. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Pharmacological elevation of sphingosine-1-phosphate by S1P lyase inhibition accelerates bone regeneration after post-traumatic osteomyelitis.

Posttraumatic osteomyelitis and the ensuing bone defects are a debilitating complication after open fractures with little therapeutic options. We have recently identified potent osteoanabolic effects of sphingosine-1-phosphate (S1P) signalling and have now tested whether it may beneficially affect bone regeneration after infection. We employed pharmacological S1P lyase inhibition by 4-deoxypyrodoxin (DOP) to raise S1P levels in vivo in an unicortical long bone defect model of posttraumatic osteomyelitis in mice. In a translational approach, human bone specimens of clinical osteomyelitis patients were treated in organ culture in vitro with DOP. Bone regeneration was assessed by µCT, histomorphometry, immunohistology and gene expression analysis. The role of S1P receptors was addressed using S1PR3 deficient mice. Here, we present data that DOP treatment markedly enhanced osteogenesis in posttraumatic osteomyelitis. This was accompanied by greatly improved osteoblastogenesis and enhanced angiogenesis in the callus accompanied by osteoclast-mediated bone remodelling. We also identified the target of increased S1P to be the S1PR3 as S1PR3-/- mice showed no improvement of bone regeneration by DOP. In the human bone explants, bone mass significantly increased along with enhanced osteoblastogenesis and angiogenesis. Our data suggest that enhancement of S1P/S1PR3 signalling may be a promising therapeutic target for bone regeneration in posttraumatic osteomyelitis.

Autologous Reconstruction After Failed Implant-Based Breast Reconstruction: A Comparative Multifactorial Outcome Analysis.

INTRODUCTION: Failure of an implant-based breast reconstruction often requires a change to an autologous procedure (salvage autologous breast reconstruction [Salv-ABR]). The aim of this study was to compare surgical and patient-reported outcomes of Salv-ABR to immediate or delayed-immediate ABR (I/DI-ABR), which has hardly been addressed in the existing literature. METHODS: All patients undergoing Salv- or I/DI-ABR between January 2014 and December 2020 were asked to participate in this study. Complication rates, the aesthetic outcome (5-point Likert scale), and quality of life (EORTC QLQ-C30 and -BR23, Breast-Q, Center for Epidemiology Studies Depression Scale) were compared between both procedures. RESULTS: Seventy patients participated in the study (Salv-ABR: n = 23; mean ± SD age, 53.5 ± 9.1 years; follow-up, 28.6 ± 18.5 month; I/DI-ABR: n = 45, mean ± SD age: 50.2 ± 7.3 years; follow-up, 32.8 ± 18.5 month). Main indication for Salv-ABR was a major capsular contracture (n = 14 [60.1%]). Early unplanned reoperation rates were significantly increased in the Salv-ABR (56.5% vs 14.9%; P < 0.01). Patients with I/DI-ABR showed a significantly improved overall aesthetic outcome (2.7 ± 0.9 vs 3.3 ± 0.7; P < 0.01) and scored significantly higher in several subscales of EORTC QLQ-C30/BR23 (Global Health Status, Role Functioning, Body Image; P < 0.05) and the Breast-Q (Psychosocial Well-being, Satisfaction with Breast; P < 0.05) compared with patients with Salv-ABR. CONCLUSIONS: Salvage ABR is associated with a higher complication rate, compromised aesthetic outcome, and quality of life compared with I/DI-ABR. This should be considered and discussed with the patient when planning any kind of reconstructive breast surgery.

The Partner Perspective on Autologous and Implant-Based Breast Reconstruction.

INTRODUCTION: Partner involvement in the decision-making process concerning breast reconstruction (BR) after a breast cancer diagnosis may be very supportive for the patient. So far, no study evaluates partner satisfaction with the outcome after BR and the relationship to patient satisfaction. The aim of this study was to assess and compare partner satisfaction of BR with autologous tissue (ABR) and prosthetic implants (IBR), respectively, and compare it to patient-reported outcomes. PATIENTS AND METHODS: All patients undergoing ABR and IBR between January 2014 and December 2020 were asked to participate with their partners. Patient and partner satisfaction with breast reconstruction, overall outcome as well as patient's perceived and self-reported psychosocial well-being were evaluated using the Breast-Q and a modified partner questionnaire, respectively. RESULTS: Fifty-three couples participated (IBR: n=30, ABR: n = 23). Patient and partner satisfaction with breast (r = 0.552), outcome (r = 0.465) as well as patient's perceived and self-report psychosocial well-being (r = 0.495) were highly correlated with partners scoring significantly higher (p<0.001). In terms of partner satisfaction, both reconstructive procedures achieved satisfactory results. ABR scored higher in terms of softness of breast and how natural the breast feels to touch whereas IBR was rated superior evaluating the breast size. CONCLUSION: Both reconstructive procedures achieve satisfactory results in terms partner satisfaction whereas patient's psychosocial well-being was highly overestimated by their partners. Hence, partner inclusion in the regular psycho-oncological support might further sensitize them of the high psychological burden of a breast cancer diagnosis and therefore stabilize patients private support system. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Human trust in otherware - a systematic literature review bringing all antecedents together.

Technological systems are becoming increasingly smarter, which causes a shift in the way they are seen: from tools used to execute specific tasks to social counterparts with whom to cooperate. To ensure that these interactions are successful, trust has proven to be the most important driver. We conducted an extensive and structured review with the goal to reveal all previously researched antecedents influencing the human trust in technology-based counterparts. In doing so, we synthesised 179 papers and uncovered 479 trust antecedents. We assigned these antecedents to four main groups. Three of them have been explored before: environment, trustee, and trustor. Within this paper, we argue for a fourth group, the interaction. This quadripartition allows the inclusion of antecedents that were not considered previously. Moreover, we critically question the practice of uncovering more and more trust antecedents, which already led to an opaque plethora and thus becomes increasingly complex for practitioners.Practitioner summary: Future designers of intelligent and interactive technology will have to consider trust to a greater extent. We emphasise that there are far more trust antecedents - and interdependencies - to consider than the ethically motivated discussions about "Trustworthy AI" suggest. For this purpose, we derived a trust map as a sound basis.

Wnt3a and ASCs are capable of restoring mineralization in staph aureus-infected primary murine osteoblasts.

INTRODUCTION: Bone infections are one of the main reasons for impaired bone regeneration and non-union formation. In previous experimental animal studies we could already demonstrate that bone defects due to prior infections showed a markedly reduced healing capacity, which could effectively be enhanced via application of Wnt3a and Adipose-derived stromal cells (ASCs). For a more in-depth analysis, we investigated proliferation and mineralization of cultured osteoblasts infected with staph aureus and sought to investigate effects of Wnt3a and ASCs on infected osteoblasts. MATERIALS AND METHODS: Primary murine osteoblasts were isolated from calvariae and infected with staph aureus. Infected osteoblasts received treatment via application of recombinant Wnt3a, ASC conditioned medium and were furthermore cocultured with ASCs. Osteoblasts were evaluated by Alamar blue assay for metabolic activity, TUNEL-assay for apoptosis, ALP and Alizarin Red staining for mineralization. In addition, immunoflourescent staining (IF) and qRT-PCR analyses were performed. RESULTS: Infected osteoblasts showed a markedly reduced ability for mineralization and increased apoptosis, which could be restored to physiological levels by Wnt3a and ASC treatment. Interestingly, metabolic activity of osteoblasts seemed to be unaffected by staph aureus infection. Additional analyses of Wnt-pathway activity revealed effective enhancement of canonical Wnt-pathway activity in Wnt3a-treated osteoblasts. CONCLUSIONS: In summary, we gained further osteoblast-related insights into pathomechanisms of reduced bone healing capacity upon infections.

Prophylactic lymphaticovenous anastomoses for resection of soft tissue tumors of the thigh to prevent secondary lymphedema-a retrospective comparative cohort analysis.

BACKGROUND: Patients with soft tissue tumors of extremities are at risk to develop secondary lymphedema after tumor resection caused by disruption of lymphatic vessels and sclerosis. Subsequently, this study aimed to evaluate the beneficial effects of lymphaticovenous anastomoses (LVAs) after soft tissue tumor resection of the thigh in a prophylactic approach. METHODS: In a retrospective cohort study, we compared eight patients with a median age of 68.5 years (49-80) who received LVAs in combination with tumor resection for treatment of soft tissue tumors of the thigh region with a prior cohort of 20 patients with a median age of 63.0 years (23-84) who received soft tissue sarcoma resection of the thigh region. All patients of LVA cohort received 1-2 LVAs (mean 1.25 ± 0.49) at the dorsum of the foot and three patients at the SEKI-point (mean 0.375 ± 0.51). Mean maximum tumor diameter of LVA group was 19.5 ± 5.2 cm and 12.3 ± 6.6 cm of control group. All patients receiving LVA were assessed for development of lymphedema via bilateral measurements of circumference and assessment of lymphedema quality of life index (LyQLI). RESULTS: One of the eight patients who received LVAs showed moderate impairment in the LyQLI at a follow-up of 12 months while 45% of the control cohort complained about symptoms of secondary lymphedema at a median follow-up of 22 months (p-values LyQLI: p = .018 [physical domain]; p = .018 [psychosocial domain]; p = .020 [practical domain]). CONCLUSION: LVAs performed in combination with tumor resection of thigh soft tissue tumors reduce negative consequences of lymph stasis and prevent development of secondary lymphedema.

The Search for the Ideal Female Breast: A Nationally Representative United-States-Census Study.

INTRODUCTION: Many studies have started to search for the perfect aesthetic breast in order to create a pars-pro-toto for reconstruction, but especially for aesthetic surgery. To date, no representative study with anatomically accurate models was performed. METHODS: In an online based United-States-census-representative survey with 1049 participants, questions regarding the preferred breast were asked utilizing lifelike morphed 3D-generated female models for the first time. Attributes such as breast pole ratio, areola size, breast direction and projection were asked. RESULTS: The results show that, contrary to what has been claimed in previous studies, an upper-pole-to-lower-pole ratio of 55:45 is preferred by both female and male participants. When it comes to breast size, on the other hand, there are clear gender-specific differences. While women opted for a cup size around B, the men preferred larger cup sizes. Moreover, the smallest depicted areola size of 30 mm was favored among all groups in the survey. DISCUSSION: Most publications used rather detrimental models for their surveys. We therefore opted for computer-generated 3D models and varied their naturalness. This enabled us to ensure a more aesthetic and accurate illustration and thus obtained more comparable and reliable results paired with the representation of the US-population. Taken together this study unveiled unexpected insights into the population favored breast attributes that might change operative planning in breast surgery. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .

Hierarchical Ceramic Coating Reduces Adherence of Cells, Blood, Bacteria, and Tissue on Titanium Microsurgical Instruments.

BACKGROUND: Progress in the field of microsurgery allows more detailed reconstructions of the smallest tissue structures. The applied instruments are left with biological residues after coming into contact with body fluids or tissue, leading to compromised surgical precision. Designing of residue-free innovative instruments would reduce the necessity of subsidiary practices and would improve the surgical precision. METHODS: We designed a ceramic coating (Lotus ceramic coating system 26-LCC-26) that exhibits self-cleaning surface properties on coated titanium specimens. A titanium surface was modified by blasting technology and electropolishing, followed by applying a high-performance ceramic and sol-gel finish layer. The physical surface characterization was performed by scanning electron microscopy and measuring the contact angle. The cell-repellent properties and cytotoxicity were investigated using live-dead staining, BrdU, and lactate dehydrogenase assay. Furthermore, bacterial and fluid-adhesion tests were performed. Finally, blood compatibility was analyzed according to DIN ISO 10993. RESULTS: The composite system LCC-26 increased the hydrophobic character of the titanium surface (the water contact angle of 74.9 degrees was compared with 62.7 degrees of the uncoated native titanium; p < 0.01) and led to the fluid and cell-repellent properties shown by the reduction in fibroblast adherence by ∼50.7% (p < 0.05), the reduction in Staphylococcus aureus pathogen colonization by 74.1% (p < 0.001), and the decrease in erythrocyte adherence by 62.9% (p < 0.01). Furthermore, the LCC-26 coated titanium microforceps dipped in human whole blood exhibited blood-repellent character (reduction in blood adherence by 46.1%; p < 0.05). Additionally, cyto- and hemocompatibility was guaranteed in direct and indirect tests. CONCLUSION: Titanium surface modification on surgical instruments exhibits cell, bacteria, and blood-repellent properties with a full guarantee of cyto- and hemocompatibility. Thus, innovatively coated instruments could contribute to increased precision during microsurgical interventions and optimized medical operation routines in the future.

Trust in artificial intelligence within production management - an exploration of antecedents.

Industry 4.0, big data, predictive analytics, and robotics are leading to a paradigm shift on the shop floor of industrial production. However, complex, cognitive tasks are also subject of change, due to the development of artificial intelligence (AI). Smart assistants are finding their way into the world of knowledge work and require cooperation with humans. Here, trust is an essential factor that determines the success of human-AI cooperation. Within this article, an analysis within production management identifies possible antecedent variables on trust in AI and evaluates these due to interaction scenarios with AI. The results of this research are five antecedents for human trust in AI within production management. From these results, preliminary design guidelines are derived for a socially sustainable human-AI interaction in future production management systems. Practitioner summary: In the future, artificial intelligence will assist cognitive tasks in production management. In order to make good decisions, humans trust in AI has to be well calibrated. For trustful human-AI interactions, it is beneficial that humans subjectively perceive AI as capable and comprehensible and that they themselves are digitally competent.

Comparative proteomic analysis of osteogenic differentiated human adipose tissue and bone marrow-derived stromal cells.

Mesenchymal stromal cells are promising candidates for regenerative applications upon treatment of bone defects. Bone marrow-derived stromal cells (BMSCs) are limited by yield and donor morbidity but show superior osteogenic capacity compared to adipose-derived stromal cells (ASCs), which are highly abundant and easy to harvest. The underlying reasons for this difference on a proteomic level have not been studied yet. Human ASCs and BMSCs were characterized by FACS analysis and tri-lineage differentiation, followed by an intraindividual comparative proteomic analysis upon osteogenic differentiation. Results of the proteomic analysis were followed by functional pathway analysis. 29 patients were included with a total of 58 specimen analysed. In these, out of 5148 identified proteins 2095 could be quantified in >80% of samples of both cell types, 427 in >80% of ASCs only and 102 in >80% of BMSCs only. 281 proteins were differentially regulated with a fold change of >1.5 of which 204 were higher abundant in BMSCs and 77 in ASCs. Integrin cell surface interactions were the most overrepresented pathway with 5 integrins being among the proteins with highest fold change. Integrin 11a, a known key protein for osteogenesis, could be identified as strongly up-regulated in BMSC confirmed by Western blotting. The integrin expression profile is one of the key distinctive features of osteogenic differentiated BMSCs and ASCs. Thus, they represent a promising target for modifications of ASCs aiming to improve their osteogenic capacity and approximate them to that of BMSCs.

Antibiotic prophylaxis for prevention of wound infections after soft tissue sarcoma resection: A retrospective cohort study.

BACKGROUND AND OBJECTIVES: The use of antibiotic prophylaxis for soft tissue sarcoma resection varies widely while little evidence on this topic exists. The aim of this study was to determine the impact of antibiotic prophylaxis on the occurrence of wound infections. METHODS: A single institutional retrospective cohort study was performed on patients who underwent truncal or extremity soft tissue sarcoma resection. The use of antibiotic prophylaxis was assessed and univariate and multivariate analysis of predictors of wound infections was performed. RESULTS: Nine hundred and fifty-eight patients could be included. Thirty-two percent of patients had no antibiotic prophylaxis, 44% of patients received single-shot prophylaxis, and 24% of patients received single-shot plus continued antibiotic treatment. Wound infections occurred in 140 patients (15%). Independent risk factors for wound infections upon multivariate analysis were obesity, high American Society of Anesthesiologists (ASA) status, high tumor size and grade, operation time over 120 minutes, and other complications. Antibiotic prophylaxis could not be identified as a protective factor in univariate or multivariate analysis. CONCLUSIONS: A favorable effect of antibiotic prophylaxis on the occurrence of wound infections could not be observed. Although more studies on this subject are needed, our data do not support the general use of antibiotic prophylaxis for soft tissue sarcoma resection.

Regulatory aspects of myogenic factors GDF-8 and Follistatin on the intake of combined oral contraceptives.

Combined oral contraceptives are one of the most prescribed drugs in the western world. While there is little evidence regarding effects of estrogen or gestagens on muscle metabolism, androgens are well-known for their anabolic characteristics. In this study, we seeked to investigate potential correlations of the myokines GDF-8, IGF-1 and Follistatin with female sexual hormones and likewise possible interactions with combined oral contraceptives (Dienogest and Ethyl Estradiol) intake. We obtained serum samples of young healthy women to measure hormone correlations. Furthermore, we simulated combined oral contraceptive blood circulating hormone concentrations to identify myogenic effects on HSkM in vitro. GDF-8, IGF-1 and Follistatin showed concentration correlations (p = .005) in overall patients' serum, while Follistatin as a promyogenic protein additionally showed a positive correlation with testosterone and estradiol (p < .05). Lower GDF-8 levels were also linked to a higher BMI (p = .009). Upon combined oral contraceptives (COC) intake, patients showed decreased GDF-8 (p = .006) but increased Follistatin (p = .0001) concentrations compared to patients without COC intake. In vitro, addition of Ethyl Estradiol and Dienogest to HSkM cells revealed a pro-myogenic, proliferative, chemosensitized pattern. Our data support a pro-myogenic effect of combined oral contraceptives.

Assessing cell-specific effects of genetic variations using tRNA microarrays.

BACKGROUND: By definition, effect of synonymous single-nucleotide variants (SNVs) on protein folding and function are neutral, as they alter the codon and not the encoded amino acid. Recent examples indicate tissue-specific and transfer RNA (tRNA)-dependent effects of some genetic variations arguing against neutrality of synonymous SNVs for protein biogenesis. RESULTS: We performed systematic analysis of tRNA abunandance across in various models used in cystic fibrosis (CF) research and drug development, including Fischer rat thyroid (FRT) cells, patient-derived primary human bronchial epithelia (HBE) from lung biopsies, primary human nasal epithelia (HNE) from nasal curettage, intestinal organoids, and airway progenitor-directed differentiation of human induced pluripotent stem cells (iPSCs). These were compared to an immortalized CF bronchial cell model (CFBE41o-) and two widely used laboratory cell lines, HeLa and HEK293. We discovered that specific synonymous SNVs exhibited differential effects which correlated with variable concentrations of cognate tRNAs. CONCLUSIONS: Our results highlight ways in which the presence of synonymous SNVs may alter local kinetics of mRNA translation; and thus, impact protein biogenesis and function. This effect is likely to influence results from mechansistic analysis and/or drug screeining efforts, and establishes importance of cereful model system selection based on genetic variation profile.

Inflammatory processes and elevated osteoclast activity chaperon atrophic non-union establishment in a murine model.

BACKGROUND: Delayed bone healing, especially in long bones poses one of the biggest problems in orthopeadic and reconstructive surgery and causes tremendous costs every year. There is a need for exploring the causes in order to find an adequate therapy. Earlier investigations of human scaphoid non-union revealed an elevated osteoclast activity, accompanied by upregulated levels of TGF-beta and RANKL. Interestingly, scaphoid non-union seemed to be well vascularized. METHODS: In the current study, we used a murine femur-defect model to study atrophic non unions over a time-course of 10 weeks. Different time points were chosen, to gather insights into the dynamic processes of non-union establishment. RESULTS: Histological analyses as well as western blots and qRT-PCR indicated enhanced osteoclast activity throughout the observation period, paralleled by elevated levels of TGF-beta, TNF-alpha, MMP9, MMP13 and RANKL, especially during the early phases of non-union establishment. Interestingly, elevated levels of these mediators decreased markedly over a period of 10 weeks, as inflammatory reaction during non-union establishment seemed to wear out. To our surprise, osteoblastogenesis seemed to be unaffected during early stages of non-union establishment. CONCLUSION: Taken together, we gained first insights into the establishment process of atrophic non unions, in which inflammatory processes accompanied by highly elevated osteoclast activity seem to play a leading role.

Targeted capture-based NGS is superior to multiplex PCR-based NGS for hereditary BRCA1 and BRCA2 gene analysis in FFPE tumor samples.

BACKGROUND: With the introduction of Olaparib treatment for BRCA-deficient recurrent ovarian cancer, testing for somatic and/or germline mutations in BRCA1/2 genes in tumor tissues became essential for treatment decisions. In most cases only formalin-fixed paraffin-embedded (FFPE) samples, containing fragmented and chemically modified DNA of minor quality, are available. Thus, multiplex PCR-based sequencing is most commonly applied in routine molecular testing, which is predominantly focused on the identification of known hot spot mutations in oncogenes. METHODS: We compared the overall performance of an adjusted targeted capture-based enrichment protocol and a multiplex PCR-based approach for calling of pathogenic SNVs and InDels using DNA extracted from 13 FFPE tissue samples. We further applied both strategies to seven blood samples and five matched FFPE tumor tissues of patients with known germline exon-spanning deletions and gene-wide duplications in BRCA1/2 to evaluate CNV detection based solely on panel NGS data. Finally, we analyzed DNA from FFPE tissues of 11 index patients from families suspected of having hereditary breast and ovarian cancer, of whom no blood samples were available for testing, in order to identify underlying pathogenic germline BRCA1/2 mutations. RESULTS: The multiplex PCR-based protocol produced inhomogeneous coverage among targets of each sample and between samples as well as sporadic amplicon drop out, leading to insufficiently or non-covered nucleotides, which subsequently hindered variant detection. This protocol further led to detection of PCR-artifacts that could easily have been misinterpreted as pathogenic mutations. No such limitations were observed by application of an adjusted targeted capture-based protocol, which allowed for CNV calling with 86% sensitivity and 100% specificity. All pathogenic CNVs were confirmed in the five matched FFPE tumor samples from patients carrying known pathogenic germline mutations and we additionally identified somatic loss of the second allele in BRCA1/2. Furthermore we detected pathogenic BRCA1/2 variants in four the eleven FFPE samples from patients of whom no blood was available for analysis. CONCLUSIONS: We demonstrate that an adjusted targeted capture-based enrichment protocol is superior to commonly applied multiplex PCR-based protocols for reliable BRCA1/2 variant detection, including CNV-detection, using FFPE tumor samples.

Myostatin Upregulation in Patients in the Chronic Phase of Severe Burn Injury Leads to Muscle Cell Catabolism.

BACKGROUND: Burn injury leads to a hypercatabolic response and ultimately muscle wasting with drastic implications for recovery of bodily functions, patient's quality of life (QoL), and long-term survival. Several treatment options target the body's initial stress response, but pharmacological approaches to specifically address muscle protein metabolism have only been poorly investigated. OBJECTIVE: The aim of this study was to assess the role of myostatin and follistatin in burn injury and its possible implications in muscle wasting syndrome. METHODS: We harvested serum from male patients within 48 h and again 9-12 months after severe burn injury (>20% of total body surface area). By means of myoblast cultures, immunohistochemistry, immunoblotting, and scratch assay, the role of myostatin and its implications in post-burn muscle metabolism and myoblast proliferation and differentiation was analyzed. RESULTS: We were able to show increased proliferative and myogenic capacity, decreased myostatin, decreased SMAD 2/3, and elevated follistatin concentrations in human skeletal myoblast cultures with serum conditioned medium of patients in the acute phase of burn injury and conversely a reversed situation in patients in the chronic phase of burn injury. Thus, there is a biphasic response to burn trauma, initiated by an anabolic state and followed by long-term hypercatabolism. CONCLUSION: We conclude that the myostatin signaling pathway plays an important regulative role in burn-associated muscle wasting and that blockade of myostatin could prove to be a valuable treatment approach improving the rehabilitation process, QoL, and long-term survival after severe burn injury.

Noncoding copy-number variations are associated with congenital limb malformation.

PurposeCopy-number variants (CNVs) are generally interpreted by linking the effects of gene dosage with phenotypes. The clinical interpretation of noncoding CNVs remains challenging. We investigated the percentage of disease-associated CNVs in patients with congenital limb malformations that affect noncoding cis-regulatory sequences versus genes sensitive to gene dosage effects.MethodsWe applied high-resolution copy-number analysis to 340 unrelated individuals with isolated limb malformation. To investigate novel candidate CNVs, we re-engineered human CNVs in mice using clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing.ResultsOf the individuals studied, 10% harbored CNVs segregating with the phenotype in the affected families. We identified 31 CNVs previously associated with congenital limb malformations and four novel candidate CNVs. Most of the disease-associated CNVs (57%) affected the noncoding cis-regulatory genome, while only 43% included a known disease gene and were likely to result from gene dosage effects. In transgenic mice harboring four novel candidate CNVs, we observed altered gene expression in all cases, indicating that the CNVs had a regulatory effect either by changing the enhancer dosage or altering the topological associating domain architecture of the genome.ConclusionOur findings suggest that CNVs affecting noncoding regulatory elements are a major cause of congenital limb malformations.

Age-dependent alterations in osteoblast and osteoclast activity in human cancellous bone.

It is assumed that the activity of osteoblasts and osteoclasts is decreased in bone tissue of aged individuals. However, detailed investigation of the molecular signature of human bone from young compared to aged individuals confirming this assumption is lacking. In this study, quantitative expression analysis of genes related to osteogenesis and osteoclastogenesis of human cancellous bone derived from the distal radius of young and aged individuals was performed. Furthermore, we additionally performed immunohistochemical stainings. The young group included 24 individuals with an average age of 23.2 years, which was compared to cancellous bone derived from 11 body donators with an average age of 81.0 years. In cancellous bone of young individuals, the osteogenesis-related genes RUNX-2, OSTERIX, OSTEOPONTIN and OSTEOCALCIN were significantly up-regulated compared to aged individuals. In addition, RANKL and NFATc1, both markers for osteoclastogenesis, were significantly induced in cancellous bone of young individuals, as well as the WNT gene family member WNT5a and the matrix metalloproteinases MMP-9. However, quantitative RT-PCR analysis of BMP-2, ALP, FGF-2, CYCLIN-D1, MMP-13, RANK, OSTEOPROTEGERIN and TGFb1 revealed no significant difference. Furthermore, Tartrate-resistant acid phosphatase (TRAP) staining was performed which indicated an increased osteoclast activity in cancellous bone of young individuals. In addition, pentachrome stainings revealed significantly less mineralized bone matrix, more osteoid and an increased bone density in young individuals. In summary, markers related to osteogenesis as well as osteoclastogenesis were significantly decreased in the aged individuals. Thus, the present data extends the knowledge about reduced bone regeneration and healing capacity observed in aged individuals.

Microdeletions on 6p22.3 are associated with mesomelic dysplasia Savarirayan type.

INTRODUCTION: Mesomelic dysplasias are a group of skeletal disorders characterised by shortness of the middle limb segments (mesomelia). They are divided into 11 different categories. Among those without known molecular basis is mesomelic dysplasia Savarirayan type, characterised by severe shortness of the middle segment of the lower limb. OBJECTIVE: To identify the molecular cause of mesomelic dysplasia Savarirayan type. METHODS AND RESULTS: We performed array comparative genomic hybridisation in three unrelated patients with mesomelic dysplasia Savarirayan type and identified 2 Mb overlapping de novo microdeletions on chromosome 6p22.3. The deletions encompass four known genes: MBOAT1, E2F3, CDKAL1 and SOX4. All patients showed mesomelia of the lower limbs with hypoplastic tibiae and fibulae. We identified a fourth patient with intellectual disability and an overlapping slightly larger do novo deletion also encompassing the flanking gene ID4. Given the fact that the fourth patient had no skeletal abnormalities and none of the genes in the deleted interval are known to be associated with abnormalities in skeletal development, other mutational mechanisms than loss of function of the deleted genes have to be considered. Analysis of the genomic region showed that the deletion removes two regulatory boundaries and brings several potential limb enhancers into close proximity of ID4. Thus, the deletion could result in the aberrant activation and misexpression of ID4 in the limb bud, thereby causing the mesomelic dysplasia. CONCLUSIONS: Our data indicate that the distinct deletion 6p22.3 is associated with mesomelic dysplasia Savarirayan type featuring hypoplastic, triangular-shaped tibiae and abnormally shaped or hypoplastic fibulae.