Exploring Anti-Fibrotic Effects of Adipose-Derived Stem Cells: Transcriptome Analysis upon Fibrotic, Inflammatory, and Hypoxic Conditioning

Autologous fat transfers show promise in treating fibrotic skin diseases, reversing scarring and stiffness, and improving quality of life. Adipose-derived stem cells (ADSCs) within these grafts are believed to be crucial for this effect, particularly their secreted factors, though the specific mechanisms remain unclear. This study investigates transcriptomic changes in ADSCs after in vitro fibrotic, inflammatory, and hypoxic conditioning. High-throughput gene expression assays were conducted on ADSCs exposed to IL1-β, TGF-β1, and hypoxia and in media with fetal bovine serum (FBS). Flow cytometry characterized the ADSCs. RNA-Seq analysis revealed distinct gene expression patterns between the conditions. FBS upregulated pathways were related to the cell cycle, replication, wound healing, and ossification. IL1-β induced immunomodulatory pathways, including granulocyte chemotaxis and cytokine production. TGF-β1 treatment upregulated wound healing and muscle tissue development pathways. Hypoxia led to the downregulation of mitochondria and cellular activity.

An Updated Systematic Review and Meta-analysis of the Impact of Graduated Compression Stockings in Addition to Pharmacological Thromboprophylaxis for Prevention of Venous Thromboembolism in Surgical Inpatients

OBJECTIVE

To compare the rate of venous thromboembolism (VTE) in surgical inpatients with pharmacological thromboprophylaxis and additional graduated compression stockings (GCSs) versus pharmacological thromboprophylaxis alone.

BACKGROUND

Surgical inpatients have elevated VTE risk; recent studies cast doubt on whether GCS confers additional protection against VTE, compared with pharmacological thromboprophylaxis alone.

METHODS

The review followed "Preferred Reporting Items for Systematic Reviews and Meta-analyses" guidelines using a registered protocol (CRD42017062655). The MEDLINE and Embase databases were searched up to November 2022. Randomized trials reporting VTE rate after surgical procedures, utilizing pharmacological thromboprophylaxis, with or without GCS, were included. The rates of deep venous thrombosis (DVT), pulmonary embolism, and VTE-related mortality were pooled through fixed and random effects.

RESULTS

In a head-to-head meta-analysis, the risk of DVT for GCS and pharmacological thromboprophylaxis was 0.85 (95% CI: 0.54-1.36) versus for pharmacological thromboprophylaxis alone (2 studies, 70 events, 2653 participants). The risk of DVT in pooled trial arms for GCS and pharmacological thromboprophylaxis was 0.54 (95% CI: 0.23-1.25) versus pharmacological thromboprophylaxis alone (33 trial arms, 1228 events, 14,108 participants). The risk of pulmonary embolism for GCS and pharmacological prophylaxis versus pharmacological prophylaxis alone was 0.71 (95% CI: 0.0-30.0) (27 trial arms, 32 events, 11,472 participants). There were no between-group differences in VTE-related mortality (27 trial arms, 3 events, 12,982 participants).

CONCLUSIONS

Evidence from head-to-head meta-analysis and pooled trial arms demonstrates no additional benefit for GCS in preventing VTE and VTE-related mortality. GCS confer a risk of skin complications and an economic burden; current evidence does not support their use for surgical inpatients.

Refinement of the Superomedial Pedicle Technique: A New Approach to Breast Reshaping Following Reduction

INTRODUCTION

We present an alteration of the superomedial pedicle technique in breast reduction to control lateral fullness and create a more natural and contoured breast during reshaping. This approach has been adopted by the senior author (NC) in 79 patients over the past 4 years.

METHODS

A wise pattern skin incision is used, and the nipple-areola complex (NAC) is maintained on a de-epithelialized superomedial pedicle. Instead of fully releasing the pedicle from the lateral parenchyma for rotation and inset, a bridge of tissue between the pedicle on its most posterior aspect and the lateral pillar is maintained. Key holding sutures are subsequently placed in Scarpa's fascia for reshaping.

RESULTS

We find that with this refinement, the connection with the lateral pillar pulls the lateral parenchyma medially and superiorly when the pedicle is rotated into its new position, adding a natural curve to the side. The superior medial pedicle is still attached in its postero-lateral aspect to the lateral pillar and theoretically, will provide an even more robust vascular supply to the NAC. In our series, three patients developed minor skin healing issues amenable to treatment with dressings. No one suffered from nipple loss or other serious complications, and no dog ear revisions were required.

CONCLUSIONS

We present a simple alteration of the superomedial pedicle technique that we believe results in improved breast contouring. Our experience suggests that this simple adaptation is safe, effective, and reproducible.

LEVEL OF EVIDENCE IV

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 .

Systematic Review and Meta-analysis of the Additional Benefit of Pharmacological Thromboprophylaxis for Endovenous Varicose Vein Interventions

OBJECTIVE

The primary objective of this systematic review and meta-analysis was to elucidate the rate of venous thromboembolism (VTE) after endovenous interventions for varicose veins in the presence of pharmacological and mechanical thromboprophylaxis versus mechanical thromboprophylaxis alone.

BACKGROUND

The VTE rate after endovenous procedures for varicose veins is higher than other day-case procedures and could be reduced with pharmacological thromboprophylaxis.

METHODS

The review followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines with a registered protocol (PROSPERO: CRD42021274963). Studies of endovenous intervention for superficial venous incompetence reporting the predefined outcomes with at least 30 patients were eligible. Data were pooled with a fixed effects model.

RESULTS

There were 221 trials included in the review (47 randomized trial arms, 105 prospective cohort studies, and 69 retrospective studies). In randomized trial arms, the rate of deep venous thrombosis with additional pharmacological thromboprophylaxis was 0.52% (95% CI, 0.23%-1.19%) (9 studies, 1095 patients, 2 events) versus 2.26% (95% CI, 1.81%-2.82%) (38 studies, 6951 patients, 69 events) with mechanical thromboprophylaxis alone. The rate of pulmonary embolism in randomized trial arms with additional pharmacological thromboprophylaxis was 0.45% (95% CI, 0.09-2.35) (5 studies, 460 participants, 1 event) versus 0.23% (95% CI, 0.1%-0.52%) (28 studies, 4834 participants, 3 events) for mechanical measures alone. The rate of EHIT grade III to IV was 0.35% (95% CI, 0.09-1.40) versus 0.88% (95% CI, 0.28%-2.70%). There was 1 VTE-related mortality and 1 instance of major bleeding, with low rates of minor bleeding.

CONCLUSIONS

There is a significant reduction in the rate of DVT with additional pharmacological thromboprophylaxis and routine prescription of anticoagulation after endovenous varicose vein intervention should be considered. VTE risk for individual study participants is heterogeneous and risk stratification in future randomized interventional studies is critical to establish the clinical effectiveness and safety of additional pharmacological thromboprophylaxis.

Single-Cell Analysis of ADSC Interactions with Fibroblasts and Endothelial Cells in Scleroderma Skin

Adipose-derived stem cells (ADSCs) as part of autologous fat grafting have anti-fibrotic and anti-inflammatory effects, but the exact mechanisms of action remain unknown. By simulating the interaction of ADSCs with fibroblasts and endothelial cells (EC) from scleroderma (SSc) skin in silico, we aim to unravel these mechanisms. Publicly available single-cell RNA sequencing data from the stromal vascular fraction of 3 lean patients and biopsies from the skin of 10 control and 12 patients with SSc were obtained from the GEO and analysed using R and Seurat. Differentially expressed genes were used to compare the fibroblast and EC transcriptome between controls and SSc. GO and KEGG functional enrichment was performed. Ligand-receptor interactions of ADSCs with fibroblasts and ECs were explored with LIANA. Pro-inflammatory and extracellular matrix (ECM) interacting fibroblasts were identified in SSc. Arterial, capillary, venous and lymphatic ECs showed a pro-fibrotic and pro-inflammatory transcriptome. Most interactions with both cell types were based on ECM proteins. Differential interactions identified included NTN1, VEGFD, MMP2, FGF2, and FNDC5. The ADSC secretome may disrupt vascular and perivascular inflammation hubs in scleroderma by promoting angiogenesis and especially lymphangiogenesis. Key phenomena observed after fat grafting remain unexplained, including modulation of fibroblast behaviour.

Systematic Review and Meta-Analysis of the Pooled Rate of Post-Thrombotic Syndrome After Isolated Distal Deep Venous Thrombosis

OBJECTIVE

To identify the rate of post-thrombotic syndrome (PTS) after isolated distal deep venous thrombosis (IDDVT) by performing a meta-analysis of the rate of PTS across randomised and observational studies.

DATA SOURCES

MEDLINE, Embase, the Cochrane Controlled Trials Register, Clinicaltrials.gov, European Union Clinical Trials, International Standard Randomised Controlled Trial Number, and the Australian and New-Zealand Trials Registries.

REVIEW METHODS

This review followed PRISMA guidelines using a registered protocol (CRD42021282136). Databases were searched up to December 2021 and prospective studies reporting the development of post-thrombotic syndrome were included; these were pooled with the meta-analysis.

RESULTS

The results showed a post-thrombotic rate of 17% (95% CI 11 - 26%) (seven studies, 217 cases, 1 105 participants). Heterogeneity was high (I2 = 89%). On meta-regression, the rate of post-thrombotic syndrome was not correlated with the length of follow up (p = .71). Three studies (302 participants) reported the severity of post-thrombotic syndrome: 78% were mild (Villalta score 5 - 9); 11% were moderate (Villalta score 10 - 14), and 11% were severe (Villalta score ≥ 15).

CONCLUSION

The risk of post-thrombotic syndrome after IDDVT was one in five and the risk of severe clinical manifestations, including ulceration, was one in 50. There was significant clinical, methodological, and statistical heterogeneity between studies and a substantial risk of bias from pooled studies. Randomised trials to support interventions for prevention of post-thrombotic syndrome are urgently needed.

“Achieving Optimal Clinical Outcomes in Autologous Fat Grafting: A Systematic Review of Processing Techniques”

BACKGROUND

Autologous fat grafting (AFG) is a versatile technique in reconstructive and cosmetic surgery. Graft processing is a key source of variability resulting in unreliable clinical outcomes, with no consensus on the optimal methodology. This systematic review identifies the evidence base supporting different processing paradigms.

METHODS

A systematic literature search was conducted using the PubMed, Scopus and The Cochrane Foundation databases. Studies comparing AFG processing methods and reporting long-term patient outcomes were identified.

RESULTS

Twenty-four studies (2413 patients) were identified. Processing techniques evaluated included centrifugation, decantation, washing, filtration, gauze rolling, as well as commercial devices and adipose-derived stem/stromal cell (ASC) enrichment methods. Objective volumetric and subjective patient-reported outcomes were discussed. There was a variable reporting of complications and volume retention rates. Complications were infrequent; palpable cysts (0-20%), surgical-site infections (0-8%) and fat necrosis (0-58.4%) were the most reported. No significant differences in long-term volume retention between techniques were found in AFG in the breast. In head and neck patients, greater volume retention was documented in ASC enrichment (64.8-95%) and commercial devices (41.2%) compared to centrifugation (31.8-76%).

CONCLUSIONS

Graft processing through washing and filtration, including when incorporated into commercial devices, results in superior long-term outcomes compared to centrifugation and decantation methods. ASC enrichment methods and commercial devices seem to have superior long-term volume retention in facial fat grafting.

Systematic review and meta-analysis of exercise therapy for venous leg ulcer healing and recurrence

OBJECTIVE

National guidelines in the United Kingdom have recommended regular exercise for individuals with venous leg ulceration. However, data on the effects of exercise on ulcer healing and recurrence are sparse. In the present study, we aimed to quantify the evidence for exercise regarding venous ulcer healing with respect to the primary outcomes of the proportion of healed ulcers and rate of ulcer recurrence. The secondary outcomes were improvement in ulcer symptoms, ulcer healing time, quality of life, compliance, and adverse events reported.

METHODS

The review followed PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines using a registered protocol (CRD42021220925). The MEDLINE and Embase databases and Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, European Union Clinical Trials, and International Standard Randomised Controlled Trial Number registries were searched up to April 6, 2022 and included studies comparing exercise therapy and compression vs compression alone. Data for the proportion of healed ulcers were pooled using a fixed effects meta-analysis.

RESULTS

After screening 1046 reports, 7 were included, with 121 participants allocated to exercise therapy and 125 to compression alone. All the reports were of randomized controlled trials and had reported ulcer healing at 12 weeks, with a pooled relative risk of ulcer healing of 1.38 for exercise vs compression (95% confidence interval, 1.11-1.71). Only one study had reported on recurrence; thus, data pooling was not performed. No differences between exercise and usual care were demonstrated. Compliance with exercise ranged from 33% to 81%. The included studies demonstrated low enrollment and a high risk of bias. Also, most of the trials had failed to demonstrate any differences in activity completed between the intervention and control arms.

CONCLUSIONS

A paucity of studies has examined leg ulcer recurrence after exercise programs, with no evidence to show that exercise is beneficial. Furthermore, the quality of evidence supporting exercise as an adjunct to ulcer healing is very low, and the trials demonstrated serious methodologic flaws, chiefly in recording the activity undertaken by the participants in the intervention arm. Future randomized controlled trials should implement activity monitoring and standardize the reporting of key patient, ulcer, and reflux characteristics to enable future meaningful meta-analyses to determine the role of exercise as an adjunct to venous leg ulceration healing.

Systematic review of exercise therapy in the management of post-thrombotic syndrome

Objectives

Exercise improves haemodynamic parameters in patients with chronic venous disease. There is a paucity of evidence on its effect in post-thrombotic syndrome (PTS). The aim of this systematic review is to assess the impact of exercise in PTS.

Methods

Adhering to PRISMA guidelines and following PROSPERO registration (CRD42021220924), MEDLINE, Cochrane Library, EMBASE database, and trial registries were searched on 19th May 2022.

Results

One article met the inclusion criteria and a narrative synthesis was carried out. The included randomised controlled trial reported a between-group mean difference of 4.6 points ( p = .027) in the VEINES-QOL score and −2.0 points ( p = .14) in the Villalta score, in favour of exercise therapy. The statistical significance threshold was not reached.

Conclusion

Data on exercise in PTS remains sparse but exercise appears to be a safe intervention. In the context of this literature, a potential future trial and outcome reporting measures are suggested.

364 Systematic Review of Simulation-Based Training Tools in Plastic Surgery

Aim

The recent shift from traditional surgical teaching to the incorporation of simulation training in plastic surgery has resulted in the development of a variety of simulation models and tools. We aim to identify all currently available simulators and tools for plastic surgery, assess their validity and establish their effectiveness.

Method

MEDLINE and Embase were searched for articles which validate simulation models in plastic surgery. Each study was screened in accordance with the Messick validity framework, and a rating was given for each section. In order to determine the effectiveness of each study, the McGaghie model of translational outcomes was used.

Results

On screening 2104 articles, 71 were identified to discuss validity and effectiveness. Only one study was found to achieve a high score in all validity parameters and no studies achieved an effectiveness level >2.

Conclusions

With the increasing amount of simulation training tools, there must be more validity studies conducted using updated validity frameworks. In addition, there should be an increased emphasis of the relationship between these simulators and patient outcomes/surgical technique in the operating theatre in order to determine translational outcomes. More training tools evaluating both technical and nontechnical surgical skills are recommended.

349 Improving Surgical Teaching for Junior Trainees Internationally in Light of Covid-19

Aim

During the Covid-19 pandemic there has been a gross effect on surgical training at all grades. A cohort that has been affected but reported less frequently are medical students and foundation doctors (junior trainees), whose interest in the field and clinical skills may have been affected by reduced service provision.

Method

A survey of junior trainees was conducted to analyse their perceived adequacy of surgical teaching in light of the effect of Covid-19. An online teaching course was then designed to target areas of weakness identified in the survey. The content was designed with the Imperial College London surgery curriculum and was vetted by a consultant surgeon.

Results

Of the 713 people surveyed, 393 (55%) had received little or no surgical teaching and 496 (70%) respondents said they were “not” or “slightly” confident in managing common and emergency surgical presentations. A free text box highlighted that deteriorating patients, clinical decision-making, and initiating management were the greatest concerns. This was used to design an international online teaching course for junior trainees, that focused explicitly on clinical care. The sessions were run live on MindTheBleep via Facebook live, to answer questions in real time and examine cases with live audience participation, receiving feedback after every session. This model has reached trainees in >30 countries with >200 feedback responses and an average rating of 4.5/5.

Conclusions

Junior trainees are a key cohort whose interest and education in surgery has suffered due to the pandemic. An innovative, online, clinically orientated course is assisting to re-engage trainees internationally.

180 Systematic Review and Meta-Analysis of Exercise Therapy for Venous Leg Ulcer Healing and Recurrence

Aim

National guidelines recommend regular exercise for individuals with venous leg ulceration, yet data for the effect of exercise on ulcer healing and recurrence are sparse. This study aimed to quantify the evidence for exercise in venous ulcer healing with the primary outcomes of proportion of healed ulcers and rate of ulcer recurrence. Secondary outcomes were compliance and adverse events.

Method

The review followed PRISMA guidelines using a registered protocol (CRD42021220925). Medline, Embase and Cochrane Databases were searched on 15th March 2021 and included articles comparing exercise to compression therapy. Meta-analysis was performed to pool the data.

Results

After screening 994 articles, six reports were included with 109 participants allocated to exercise and 113 to compression. All articles were randomised-controlled trials and reported ulcer healing at 12 weeks, with a pooled relative risk of 1.35 ulcers for exercise versus compression (95% CI 1.07 – 1.71). Only one article reported on recurrence and data pooling was not performed, but no difference between exercise and usual care was demonstrated. Adverse events were inadequately reported and seen to be more frequent in the exercise arm. Compliance with exercise ranged from 33–81%.

Conclusions

There is increasing evidence for exercise as an adjunct to ulcer healing, however, trials were low quality with high risk of bias. This is a crucial innovation as many ulcers recur or fail to heal in spite of surgical correction of underlying venous insufficiency. There is paucity of evidence examining leg ulcer recurrence after exercise programmes and currently no evidence of benefit.

Development and content validation of the Urethroplasty Training and Assessment Tool (UTAT) for dorsal onlay buccal mucosa graft urethroplasty

OBJECTIVES

To develop and validate the Urethroplasty Training and Assessment Tool (UTAT) using Healthcare Failure Mode and Effect Analysis (HFMEA) for training and assessment of urology trainees learning this urethral reconstruction technique, as urethroplasty is the 'gold standard' treatment for long and recurrent urethral strictures and with a variety of techniques and a lack of standardised reconstructive curricula, there is a need for procedure-specific training tools to improve surgeon training and patient safety.

MATERIALS AND METHODS

This international observational study was performed over an 11-month period. The HFMEA was used to identify and evaluate hazardous stages of urethroplasty to develop the UTAT. Hazard scores were calculated for the included steps of urethroplasty. Content validation was performed by 12 expert surgeons and multidisciplinary teams from international tertiary centres.

RESULTS

The HFMEA process resulted in an internationally validated UTAT. Hazard scores ≥4 and single point weaknesses were included to implement actions and outcome measures. Content validation was achieved by circulating the process map, hazard analysis table, and developed tools. Changes were implemented based on the feedback received from expert surgeons. The content validated dorsal onlay buccal mucosa graft bulbar UTAT contained five phases, 10 processes and 23 sub-processes.

CONCLUSIONS

The modular UTAT offers a comprehensive validated training tool developed via a detailed HFMEA protocol. This may be utilised to standardise the training and assessment of urology trainees.

Aortic valve replacement with sutureless Perceval S valve: A case report of aortic root homograft failure in the setting of Streptococcus constellatus endocarditis

BACKGROUND

Surgery for failed homograft aortic root replacement with extensive calcification in the setting of endocarditis alone is very challenging.

CASE SUMMARY

We report the case of redo aortic valve replacement and mitral valve replacement, in a 39 years old presenting with a rare Streptococcus constellatus endocarditis of a previously implanted homograft root and native mitral valve, where conventional valve replacement proved nonfeasible. S. constellatus had caused severe tissue destruction and the extensive calcification in the homograft prevented conventional valve replacement with sutures. In this case, a sutureless valve provided a useful alternative surgical strategy.

DISCUSSION

We consider heavily calcified failed homografts to be a good indication for sutureless (rapid deployment) valves.

Aortic stenosis of a bicuspid aortic valve in a patient with Klippel-Feil syndrome: a case report

Background

Klippel–Feil syndrome (KFS) is a rare congenital anomaly of the cervical spine, which is associated with a number of cardiovascular malformations, including coarctation of the aorta, bicuspid aortic valve (BAoV), and aortic aneurysm. Operative management of aortic stenosis of a BAoV in a patient with KFS has not been previously reported.

Case summary

A 54-year-old Caucasian woman with known KFS presented to her local hospital for elective cholecystectomy. An ejection systolic murmur was found incidentally on preoperative workup, which was confirmed to be due to a severely stenosed BAoV. The cholecystectomy was cancelled, and the patient was referred to our centre and accepted for surgical aortic valve replacement (AVR) based on symptomatic and prognostic grounds. Anaesthetic review of cervical spine imaging showed fusion of the C2–C6 vertebral bodies and a desiccated bulging disc at C4–C5 but no significant foraminal narrowing in the lower cervical spine. Valve replacement with a mechanical aortic prosthesis resulted in an uneventful recovery and the patient was discharged home to follow-up.

Discussion

We report the first case of severe aortic valve stenosis requiring AVR in a Klippel–Feil patient, in whom the aortic valve was confirmed to be bicuspid. This report provides further evidence of an association of KFS with BAoV and strengthens the case for screening and follow-up of KFS patients for BAoV and other cardiovascular pathologies, the consequences of which may be serious.

Redo-urethroplasty for the management of recurrent urethral strictures in males: a systematic review

Purpose

Redo-urethroplasty is a challenge for any genitourethral surgeon, with a number of techniques previously described. This systematic review aims to identify the surgical techniques described in the literature and evaluate the evidence for their effectiveness in managing recurrent urethral strictures.

Materials and methods

A systematic review of the MEDLINE and EMBASE databases from 1945 to July 2018 was performed and the urethroplasty procedures were classified according to the site and surgical technique. Primary outcomes included success rates measured via re-stricture rates and the post-op maximum urinary flow rate. Secondary outcomes included complication rates and patient-reported quality of life.

Results

A total of 39 identified studies met the inclusion criteria. Twenty-two studies described the use of excision and primary anastomotic urethroplasty with success rates showing wide variability (58–100%). Success rates reported according to the site of the stricture also varied: bulbar (58–100%) and posterior (69–100%) recurrent strictures. One-stage substitution urethroplasty was described in 25 studies with success rates of 18–100%, with the best outcomes reported for bulbar (58–100%) and hypospadias-related (78.6–82%) strictures. Two-stage substitution urethroplasty was described in 12 studies with the success rates of 20–100%, with the best evidence related to hypospadias-related and posterior urethral strictures. The buccal mucosa graft was the graft source with the best evidence for substitution urethroplasty (18–100%).

Conclusions

Trends of effectiveness were identified for redo-urethroplasty modalities in different locations. However, the current levels of evidence are limited to small observational studies, highlighting the need for further larger prospective data to evaluate different techniques used for recurrent urethral strictures.

Electronic supplementary material

The online version of this article (10.1007/s00345-019-02709-7) contains supplementary material, which is available to authorized users.