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Gradual distraction with an external fixator is a widely used treatment for severe postburn ankle contracture (SPAC). However, application of external fixators is complex, and conventional two-dimensional (2D) imaging-based surgical planning is not particularly helpful due to a lack of spatial geometry. The purpose of this study was to evaluate the surgical planning process for this procedure with patient-specific three-dimension-printed models (3DPMs). In this study, patients coming from two centers were divided into two cohorts (3DPM group vs. control group) depending on whether a 3DPM was used for preoperative surgical planning. Operation duration, improvement in metatarsal-tibial angle (MTA), range of motion (ROM), the American Orthopedic Foot and Ankle Society (AOFAS) scores, complications, and patient-reported satisfaction were compared between two groups. The 3DPM group had significantly shorter operation duration than the control group ((2.0±0.3) h vs. (3.2± 0.3) h, P

Muscle flaps must have a strong vascular network to support a large tissue volume and ensure successful engraftment. We developed porcine stomach musculofascial flap matrix (PDSF) comprising extracellular matrix (ECM) and intact vasculature. PDSF had a dominant vascular pedicle, microcirculatory vessels, a nerve network, well-retained 3-dimensional (3D) nanofibrous ECM structures, and no allo- or xenoantigenicity. In-depth proteomic analysis demonstrated that PDSF was composed of core matrisome proteins (e.g., collagens, glycoproteins, proteoglycans, and ECM regulators) that, as shown by Gene Ontology term enrichment analysis, are functionally related to musculofascial biological processes. Moreover, PDSF-human adipose-derived stem cell (hASC) synergy not only induced monocytes towards IL-10-producing M2 macrophage polarization through the enhancement of hASCs' paracrine effect but also promoted the proliferation and interconnection of both human skeletal muscle myoblasts (HSMMs) and human umbilical vein endothelial cells (HUVECs) in static triculture conditions. Furthermore, PDSF was successfully prevascularized through a dynamic perfusion coculture of hASCs and HUVECs, which integrated with PDSF and induced the maturation of vascular networks

Facial thread-lifting (FTL) has gained more popularity, but the incidences of complications following FTL remain controversial. We aimed to perform a meta-analysis and systematic review to estimate the incidences of complications and to compare the short- and long-term satisfaction rates following FTL. We searched PubMed, Web of Science, Embase and Cochrane library for eligible studies. The primary outcome was the incidences of complications following FTL. The secondary outcome was the satisfaction rate immediately and 6-month after FTL. The pooled incidences of complications and 95% confidence intervals were estimated using random-effects models. A total of 26 studies were included in this meta-analysis. Swelling was the most commonly reported complication with a pooled incidence of 35%, followed by skin dimpling (10%), paresthesia (6%), thread visibility/palpability (4%), infection (2%), and thread extrusion (2%). Absorbable threads were associated with a significantly lower risk of paresthesia (3.1% vs. 11.7%) and thread extrusion (1.6% vs. 7.6%) than non-absorbable threads. Patients older than 50 years had a significantly higher risk of dimpling (16% vs. 5.6%) and infection (5.9% vs. 0.7%) than their younger counterparts. In addition, the pooled long-term satisfaction rate was significantly decreased compared to it immediately after FTL (88% vs. 98%). Non-absorbable threads and older age of patients are associated with higher risks of complications. Therefore, we recommend a judicious use of non-absorbable threads and FLT in older patients. Furthermore, it should be discussed with patients preoperatively that the rejuvenation effect of FTL may not maintain in the long-term. 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 .

The purpose of this study is to estimate the incidence of fixation-related complications following ultrasound-activated biodegradable osteosynthesis (UBO) in the treatment of craniosynostosis. The authors searched MEDLINE, PubMed, Embase, Google Scholar, and Cochrane Library from January 2005 to January 2020 for clinical studies reporting the use of UBO for fixation in the treatment of craniosynostosis. The primary outcome was the incidence of fixation-related complications, including unstable fixation; swelling, plate visibility, or palpability; infection; inflammation, sinus formation, and discharge; implant exposure; reoperation or implant removal. The pooled incidence rates were estimated using random-effects models. Of 155 studies identified, 10 were included, representing 371 patients. Forty-six (12.4%) patients presented fixation-related complications. The incidence rates of swelling/visibility/palpability, infection, and reoperation/implant removal were pooled based on the available data. The pooled incidence rate of chronic swelling/visibility/palpability was 0.21 (95% confidence interval [CI], 0.05-0.43). Sensitivity analysis by omitting the outlier study demonstrates that the incidence of swelling/visibility/palpability was 0.07 (95% CI, 0.04-0.11). The pooled incidence rate of infection and reoperation/implant removal was 0.07 (95% CI, 0.01-0.16) and 0.04 (95% CI, 0.01-0.09), respectively. Results show that although UBO can provide stable fixation, chronic swelling/visibility/palpability, infection, and reoperation for removal are not uncommon. Based on the literature, the authors recommend judicious use of UBO in patients with large frontorbital advancement and in the area of the coronal suture or other sites with thin overlying skin/subcutaneous tissue. The high possibility of chronic swelling/palpability/visibility during degradation, needs to be discussed preoperatively.

Background Secondary lymphedema is a common condition that affects patients with malignant tumors. Conservative treatments fail to provide lasting relief because they do not address the underlying pathological accumulation of excessive fat. Our aim is to clarify the molecular mechanisms of abnormal adipogenic differentiation in lymphedema adipose tissue. Methods We compared the proliferation and adipogenesis potential of adipose-derived mesenchymal stem cells (ASCs) from the lymphedema adipose tissue from liposuction specimens of 10 patients with extremity lymphedema with that of ASCs from adipose tissue from the normal upper abdomen of the same patients. Transcriptome analysis were performed to identify the differences between the two kinds of ASCs. Cyclin-dependent kinase 1 (CDK1) inhibitors were used to treat the abnormal ASCs in lymphedema adipose tissue. Results Our results demonstrate that significant functional and transcriptomic differences exist between the two kinds of ASCs. Up-regulated genes were mainly involved in cell proliferation and division while down-regulated genes were mainly associated with immune responses and inflammatory as well as osteogenic and myogenic differentiation. Furthermore, we find that the excessive proliferation and adipogenesis of ASCs from lymphedema adipose tissue returned to the normal phenotype by CDK1 inhibitors. ASCs from lymphedema adipose tissues have higher immunosuppressive effect and the cytokines related to immunosuppressive was significantly up-regulated. Conclusions In conclusion, lymphedema-associated ASCs had more rapid proliferation and a higher adipogenic differentiation capacity. CDK1 may be a key driver of proliferation and adipogenic differentiation in these cells, which might expound the accumulation of adipose tissue extensively observed in secondary lymphedema. ASCs from lymphedema adipose tissues showed immunomodulation dysfunction and immunomodulation may play an important role in the pathogenesis of lymphedema.

PurposeThe purpose of this study was to construct a gene signature comprising genes related to both inflammation and pyroptosis (GRIPs) to predict the prognosis of patients with cutaneous melanoma patients and the efficacy of immunotherapy, chemotherapy, and targeted therapy in these patients.MethodsGene expression profiles were collected from The Cancer Genome Atlas. Weighted gene co-expression network analysis was performed to identify GRIPs. Univariable Cox regression and Lasso regression further selected key prognostic genes. Multivariable Cox regression was used to construct a risk score, which stratified patients into high- and low-risk groups. Areas under the ROC curves (AUCs) were calculated, and Kaplan-Meier analyses were performed for the two groups, following validation in an external cohort from Gene Expression Omnibus (GEO). A nomogram including the GRIP signature and clinicopathological characteristics was developed for clinical use. Gene set enrichment analysis illustrated differentially enriched pathways. Differences in the tumor microenvironment (TME) between the two groups were assessed. The efficacies of immune checkpoint inhibitors (ICIs), chemotherapeutic agents, and targeted agents were predicted for both groups. Immunohistochemical analyses of the GRIPs between the normal and CM tissues were performed using the Human Protein Atlas data. The qRT-PCR experiments validated the expression of genes in CM cell lines, Hacat, and PIG1 cell lines.ResultsA total of 185 GRIPs were identified. A novel gene signature comprising eight GRIPs (TLR1, CCL8, EMP3, IFNGR2, CCL25, IL15, RTP4, and NLRP6) was constructed. The signature had AUCs of 0.714 and 0.659 for predicting 3-year overall survival (OS) in the TCGA entire and GEO validation cohorts, respectively. Kaplan-Meier analyses revealed that the high-risk group had a poorer prognosis. Multivariable Cox regression showed that the GRIP signature was an independent predictor of OS with higher accuracy than traditional clinicopathological features. The nomogram showed good accuracy and reliability in predicting 3-year OS (AUC = 0.810). GSEA and TME analyses showed that the high-risk group had lower levels of pyroptosis, inflammation, and immune response, such as lower levels of CD8+ T-cell infiltration, CD4+ memory-activated T-cell infiltration, and ICI. In addition, low-risk patients whose disease expressed PD-1 or CTLA-4 were likely to respond better to ICIs, and several chemotherapeutic and targeted agents. Immunohistochemical analysis confirmed the distinct expression of five out of the eight GRIPs between normal and CM tissues.ConclusionOur novel 8-GRIP signature can accurately predict the prognosis of patients with CM and the efficacies of multiple anticancer therapies. These GRIPs might be potential prognostic biomarkers and therapeutic targets for CM.

Preoperative radiation is associated with an increased risk of wound complications. However, the influences of radiation on musculofascial wound healing remains unclear. The purpose of the study was to investigate the short-term effects of preoperative local radiation on the musculofascial healing of laparotomy incisions in a rat model. Eighteen Fischer 344 rats received radiation doses of 0, 10, or 20 Gy to the abdominal wall and underwent laparotomy 4 weeks later. Two weeks after laparotomy, samples of irradiated muscle were harvested for mechanical tests, histological (Hematoxylin & Eosin, and Masson’s Trichrome) and immunohistochemical analyses using KI67, CD31, TGF-β, and MYOD1 antibodies. The elastic modulus (EM), maximum strain (MS), and ultimate tensile strength (UTS) in the 20-Gy group were significantly weaker than those in the 0-Gy group. The EM and UTS in the 20-Gy group were significantly lower than those in the 10-Gy group. The UTS and MS in the 10-Gy group were significantly lower than those in the 0-Gy group. The mean number of inflammatory cells per mm2 in the 20-Gy group was significantly larger than those in the 10- and 0-Gy groups. The mean numbers of CD31-, KI67-, and MYOD1-positive cells, the optical density of TGF-β, and the microvessel density in the 20-Gy group were significantly smaller than those in the 10- and 0-Gy groups. These results indicated that radiation delays musculofascial healing and decreases mechanical strength of the laparotomy incision by creating a chronic inflammatory environment, inhibiting cell proliferation, angiogenesis, granulation maturation, collagen deposition, and muscular regeneration in a dose-dependent manner. The impaired biomechanical, histological and molecular properties may be associated with the higher risk of wound complications in patients who undergo radiotherapy prior to laparotomy.

Purpose Although osteoporosis is associated with increased risks of complications of fracture fixation in the orthopedic literature, the association between local bone quality (LBQ) and complications of facial fracture fixation is unknown. The authors aim to identify that if decreased LBQ is an independent risk factor for complications following facial fracture fixation? Methods The authors conducted a prospective cohort study on patients over age of 50 years who underwent open reduction and rigid internal fixation for facial fractures. The primary predictor was LBQ (low or normal), decided by a combination of 3 panoramic indices. Other predictors included age, gender, body mass index (BMI), comorbidities, trauma-related characteristics, etc. The outcome variable was the presence of hardware-related, fracture-healing, wound, or neurosensory complications during 2-year follow-up. Univariate and multivariate regressions were performed to identify any significant association between predictor and outcome variables. Results The sample was composed of 69 patients (27 females) with an average age of 58.6 ± 8.6 years and BMI of 25 ± 3.8. Low-LBQ patients were significantly older, more females, had lower BMI, mainly injured from falls, had more complications compared to their normal-LBQ counterparts. However, multivariable logistic regressions demonstrated that only age (adjusted OR: 1.12, P = 0.031, 95% CI: 1.01, 1.23) and diabetes (adjusted OR: 12.63, P = 0.029, 95% CI: 1.3, 122.53) were significantly associated with overall complications after confounding adjustment. Conclusions The results of the present study indicate that reduced LBQ is not an independent risk factor for complications following facial fracture fixation. The increased risk of complications in low-LBQ patients is more likely to be attributed to other age-related comorbidities such as diabetes. Therefore, the authors recommend detailed workup and good control of comorbidities in elderly trauma patient.

This meta-analysis aimed to provide an up-to-date comparison of donor site morbidity (DSM) between patients who underwent head and neck reconstruction with Anterolateral thigh (ALT) and radial forearm free (RFF) flaps. We searched the PubMed, Web of Science, EMBASE, and Cochrane Library databases to identify studies that compared DSM between ALT and RFF patients. Study quality was assessed using the Newcastle-Ottawa Scale. The pooled odds ratio (OR) of each DSM between ALT and RFF patients was estimated using a random- or fixed-effect model depending on the degree of interstudy heterogeneity. Sensitivity and subgroup analyses were performed if substantial heterogeneity was detected. Eighteen cohort studies with 1,018 patients (535 ALT and 483 RFF patients) were included. Compared with RFF, ALT were associated with lower risks of wound dehiscence (OR = 0.2, 95%CI: 0.10-0.42, P

Background: Gradual distraction with external fixators such as Ilizarov frame has been widely used for the treatment of severe postburn ankle contracture (PAC). However, the application of external fixator is complex and conventional surgical planning based on 2D imaging is compromised due to a lack of spatial geometry and tactile feedback. The purpose of this study was to evaluate the surgical planning with patient-specific 3D-printed models (3DPM) for the treatment of PAC with external fixators. Methods: A two-centered retrospective cohort study, composed of consecutive patients who underwent external fixation for the treatment of severe PAC, was implemented. Patients were divided into two cohorts (3DPM group vs. Control group) according to whether 3DPM was used for preoperative surgical planning. The primary outcome variable was operation duration. Other outcome variables included improvement in metatarsal-tibial angle (MTA), range of motion (ROM), American Orthopedic Foot and Ankle Society (AOFAS) scores, and complications. Results: Between January 2008 and June 2018, ten patients with an average age of 23.8±14.1 yeas were treated for PAC at two centers. 3DPM were used for surgical planning in 5 patients. 3DPM group had significantly shorter operation duration than the control group (2±0.3 hours vs. 3.2±0.3 hours, p=0.0001). The comparison of preoperative, after removal of external fixator, and follow-up MTA, ROM, and AOFAS between the 3DPM and control group showed no significant differences. A plantigrade foot was achieved and gait was substantially improved in all patients at the final follow-up. Pin-tract infections occurred in 2 patients (one in each group) during distraction and were treated with wound care and oral antibiotics. Conclusion: The results of this study show that surgical planning using patient-specific 3DPM significantly reduced the operation duration while providing similar improvements in MTA, ROM, and AOFAS scores compared to traditional surgical planning for the correction of severe PAC with external fixators.

Occlusion caused by interaction between multiple objects makes the road scene understanding intractable. In this paper, we focus on the prediction of the objects' states by causal reasoning. In this paper, the visibility fluent is used to present the varying state of objects involving visible, occluded, and lost. Then, a Causal And-Or Graph (C-AOG) is constructed to present the causal relations. Besides, an Action And-Or Graph (A-AOG) and the influence field are proposed to encode the interaction of multi-objects. Finally, a probabilistic grammar model is proposed to jointly make inference of visibility fluents. We evaluate our approach on the synthetic data. It proves to achieve a promising performance in the prediction of the objects' states.

Adipose-derived mesenchymal stem cells (ADSCs) show considerable promise for clinical applications in regenerative medicine. We performed a large-scale single-cell transcriptomic sequencing of 24,358 cultured human ADSCs from three donors. We provide a high-quality dataset, which would be a valuable resource for dissecting the intrapopulation heterogeneity of cultured ADSCs as well as interrogating lineage priming patterns for any interested lineages at single-cell resolution.

The use of synthetic mesh (e.g., polypropylene [PP] mesh) and biologic (e.g., porcine acellular dermal matrix (PADM)) for the repair of abdominal wall musculofascial has limitations associated with an increased risk of complications and finite properties, respectively. Silk fibroin (SF)-based scaffolds are fabricated with decorin blends (SFD) to create a matrix platform with the desired structure-property function to be translated to the clinic to address patient-specific needs. PADM and SFD composites with SFD or PADM facing the peritoneal cavity were tested in an in vivo incisional ventral hernia repair model using female Hartley guinea pigs. At week 4, gross observation of adhesion grade and strength showed that the SFD, PADM, and composites resulted in fewer and weaker adhesions than did PP mesh (p < 0.05). Mechanical properties at the musculofascial-implant interface in the SFD group were similar to those of the native abdominal wall. SFD group exhibited homogeneous three-dimensional cell infiltration, vascularization, and tissue remodeling in implants. In conclusion, SFD promotes musculofascial regeneration.

Insufficient neovascularization is associated with high levels of resorption and necrosis in autologous and engineered fat grafts. We tested the hypothesis that incorporating angiogenic growth factor into a scaffold–stem cell construct and implanting this construct around a vascular pedicle improves neovascularization and adipogenesis for engineering soft tissue flaps. Poly(lactic-co-glycolic-acid/polyethylene glycol (PLGA/PEG) microspheres containing vascular endothelial growth factor (VEGF) were impregnated into collagen-chitosan scaffolds seeded with human adipose-derived stem cells (hASCs). This setup was analyzed in vitro and then implanted into isolated chambers around a discrete vascular pedicle in nude rats. Engineered tissue samples within the chambers were harvested and analyzed for differences in vascularization and adipose tissue growth. In vitro testing showed that the collagen-chitosan scaffold provided a supportive environment for hASC integration and proliferation. PLGA/PEG microspheres with slow-release VEGF had no negative effect on cell survival in collagen-chitosan scaffolds. In vivo, the system resulted in a statistically significant increase in neovascularization that in turn led to a significant increase in adipose tissue persistence after 8 weeks versus control constructs. These data indicate that our model—hASCs integrated with a collagen-chitosan scaffold incorporated with VEGF-containing PLGA/PEG microspheres supported by a predominant vascular vessel inside a chamber—provides a promising, clinically translatable platform for engineering vascularized soft tissue flap. The engineered adipose tissue with a vascular pedicle could conceivably be transferred as a vascularized soft tissue pedicle flap or free flap to a recipient site for the repair of soft-tissue defects.

The purpose of this study was to compare the clinical outcomes of ultrasonic surgery to the conventional bone cutting technique using bur and saw for the release of ankylosis of temporomandibular joint. We conducted a prospective cohort study on 25 patients with 38 ankylotic joints at Chinese PLA General Hospital from March 01, 2012 to March 01, 2016. Patients were followed up at least 2 years postoperatively. The primary outcome was the intraoperative blood loss per joint. The secondary outcome was the long-term (≥2 years) improvement of maximum mouth opening. The blood loss was significantly reduced in the ultrasonic group compared to the conventional group (107.3 ± 62.3 ml vs. 186.3 ± 92.6 ml, P = 0.019). The long-term improvements of maximum mouth opening were substantial and stable in both groups (33.5 ± 4.8 mm in the ultrasonic group vs. 29.2 ± 6 mm in the conventional group, P = 0.06). Multivariate linear regression analysis showed a significant association between blood loss and technique used (coefficient: 66.3, 95% confidence interval: 22.1,110.4, P = 0.006). The ultrasonic surgery was associated with less intraoperative blood loss when compared to the conventional method for the release of ankylosis of temporomandibular joint while providing a stable and comparable long-term improvement of maximum mouth opening.

Purpose We sought to compare cricothyroid membrane puncture–guided tracheostomy (CMPGT) with surgical cricothyroidotomy (SC) and percutaneous tracheostomy with Griggs' guidewire dilating forceps (GWDF) for establishing an emergency airway in a porcine model. We hypothesized that CMPGT would be associated with a shorter time to ventilation and more rapid restoration of oxygenation. Materials and Methods We implemented a small pilot animal study. Eighteen miniature pigs were randomly assigned to undergo CMPGT, SC, or GWDF. The predictor variable was the technique used. The primary outcome variable was time to ventilation. Other outcome variables were efficiency of oxygenation restoration, procedure duration, and procedure-related complications. The data were assessed using 1-way analysis of variance and Bonferroni correction. The oxygen saturation (SpO2) changes over time were graphed using a time-series line plot. Statistical significance was set at P Results Airways were successfully established in all 18 pigs. SC (68 ± 4 seconds) showed the shortest procedure duration compared with GWDF (95 ± 3 seconds) and CMPGT (96 ± 4 seconds); however, the time to ventilation using CMPGT (21 ± 2 seconds) was significantly shorter than that with SC (68 ± 4 seconds) and GWDF (95 ± 3 seconds) (P o 2 in each group increased postoperatively, reaching 95% at 120 seconds, 131 seconds, and 144 seconds in the CMPGT, SC, and GWDF groups, respectively. The slope of the ascending phase of the Sp o 2 curve was 0.38 for CMPGT, 0.42 for SC, and 0.53 for GWDF (P Conclusions The results of this animal study suggest that CMPGT is a time-efficient and safe technique for emergency airway access that allows for a more rapid return of ventilation and obviates conversion to definitive tracheostomy. Further cadaveric study is ongoing.

Background The success of an autologous fat graft depends in part on its total stromal vascular fraction (SVF) and adipose-derived stem cells (ASCs). However, variations in the yields of ASCs and SVF cells as a result of different harvesting techniques and donor sites are poorly understood. Objective To investigate the effects of adipose tissue harvesting technique and donor site on the yield of ASCs and SVF cells. Methods Subcutaneous fat tissues from the abdomen, flank, or axilla were harvested from patients of various ages by mechanical liposuction, direct surgical excision, or Coleman's technique with or without centrifugation. Cells were isolated and then analyzed with flow cytometry to determine the yields of total SVF cells and ASCs (CD11b−, CD45−, CD34+, CD90+, D7-FIB+). Differences in ASC and total SVF yields were assessed with one-way analysis of variance. Differentiation experiments were performed to confirm the multilineage potential of cultured SVF cells. Results Compared with Coleman's technique without centrifugation, direct excision yielded significantly more ASCs ( P < .001) and total SVF cells ( P = .007); liposuction yielded significantly fewer ASCs ( P < .001) and total SVF cells ( P < .05); and Coleman's technique with centrifugation yielded significantly more total SVF cells ( P < .005), but not ASCs. The total number of SVF cells in fat harvested from the abdomen was significantly larger than the number in fat harvested from the flank or axilla ( P < .05). Cultured SVF cells differentiated to adipocytes, osteocytes, and chondrocytes. Conclusions Adipose tissue harvested from the abdomen through direct excision or Coleman's technique with centrifugation was found to yield the most SVF cells and ASCs.

Adipose-derived stem cells (ASCs) facilitate wound healing by improving cellular and vascular recruitment to the wound site. Therefore, we investigated whether ASCs would augment a clinically relevant bioprosthetic mesh-non-cross-linked porcine acellular dermal matrix (ncl-PADM)-used for ventral hernia repairs in a syngeneic animal model. ASCs were isolated from the subcutaneous adipose tissue of Brown Norway rats, expanded, and labeled with green fluorescent protein. ASCs were seeded (2.5×10(4) cells/cm(2)) onto ncl-PADM for 24 h before surgery. In vitro ASC adhesion to ncl-PADM was assessed at 0.5, 1, and 2 h after seeding, and cell morphology on ncl-PADM was visualized by scanning electron microscopy. Ventral hernia defects (2×4 cm) were created and repaired with ASC-seeded (n=31) and control (n=32) ncl-PADM. Explants were harvested at 1, 2, and 4 weeks after surgery. Explant remodeling outcomes were evaluated using gross evaluation (bowel adhesions, surface area, and grade), histological analysis (hematoxylin and eosin and Masson's trichrome staining), immunohistochemical analysis (von Willebrand factor VIII), fluorescent microscopy, and mechanical strength measurement at the tissue-bioprosthetic mesh interface. Stem cell markers CD29, CD90, CD44, and P4HB were highly expressed in cultured ASCs, whereas endothelial and hematopoietic cell markers, such as CD31, CD90, and CD45 had low expression. Approximately 85% of seeded ASCs adhered to ncl-PADM within 2 h after seeding, which was further confirmed by scanning electron microcopy examination. Gross evaluation of the hernia repairs revealed weak omental adhesion in all groups. Ultimate tensile strength was not significantly different in control and treatment groups. Conversely, elastic modulus was significantly greater at 4 weeks postsurgery in the ASC-seeded group (p

The accuracy of predicates selectivity estimation is one of the important factors affecting query optimization performance. State-of-art selectivity estimation algorithms for string predicates based on Pruned countsuffix tree (PST) often suffer severe underestimating and overestimating problems, thus their average relative errors are not good. We analyze the main causes of the underestimating and overestimating problems, propose a novel Restricted pruned count-suffix tree (RPST) and a new pruning strategy. Based on these, we present the EKVI algorithm and the EMO algorithm which are extended from the KVI algorithm and the MO algorithm respectively. The experiments compare the EKVI algorithm and the EMO algorithm with the traditional KVI algorithm and the MO algorithm, and the results show that the average relative errors of our selectivity estimation algorithms are significantly better than the traditional selectivity estimation algorithms. The EMO algorithm is the best among these algorithms from the overall view.

Objective To investigate the effect of vascular endothelial growth factor (VEGF) overexpression on the phenotype, proliferation and multilineage differentiation ability of human adipose-derived stem cells (hADSCs). Methods Passage-2 hADSCs were transfected with pIRES2-EGFP-VEGF plasmid using DOTAP liposomal technique, whereas hADSCs in control group were transfected in absence of plasmid. The success of transfection was confirmed by immunofluorescent cytochemistry. Phenotype differences between the two groups were detected using flow cytometry. Proliferation ability was assessed using MTT assay. Adipogenic and osteogenic differentiation were induced and confirmed using Oil Red O staining and alizarin red staining. Results The transfected hADSCs expressed EGFP and VEGF, whereas no EGFP was observed in the untransfected hADSCs. Both groups of hADSCs showed high expressions of CD29, CD44, CD90, and low expressions of CD31 and CD45. Compared with the untransfected hADSCs, the transfected hADSCs exhibited significantly increased proliferation ability as well as the number of lipid droplets, calcium nodules, and the stained area. Conclusion VEGF overexpression promotes proliferation and multilineage differentiation potential of hADSCs without evident phenotype changes.

Curcumin is a potent anticancer molecule naturally derived from the spice turmeric and was combined with silk fibroin (SF) to improve its intracellular bioavailability. This study focused on the fabrication and characterization of SF nanoparticles loaded with curcumin (SF-curcumin) and evaluated their efficacy in vitro using a metastatic breast cancer cell line (GILM2). SF-curcumin nanoparticles were characterized for particle size, morphology, curcumin loading efficiency and release kinetics, efficacy against GILM2 cells, and protein expression profiles using protein microarray. Nanoparticles had an average diameter of 127.7±6.8 nm and a bimodal distribution with most particles falling within the 70- to 110-nm range. SEM showed the nanoparticles had a spherical morphology and aggregated into grape-like structures, which was confirmed using dynamic light scattering. Curcumin release from the nanoparticles showed a typical profile with an initial burst release within the first 24 hours and continued release up to 7 days. The efficacy of SF-curcumin nanoparticles in vitro improved with increased concentration of curcumin and with time. Molecular effects of nanocurcumin on GILM2 cells targeted the high expression of AKT1. Our results indicate that SF nanoparticles may be an attractive nontoxic alternative for the systemic delivery of curcumin.

Human adipose tissue extracellular matrix, derived through decellularization processing, has been shown to provide a biomimetic microenvironment for adipose tissue regeneration. This study reports the use of human adipose tissue-derived extracellular matrix (hDAM) scaffolds as a three-dimensional cell culturing system for the investigation of breast cancer growth and drug treatments. The hDAM scaffolds have similar extracellular matrix composition to the microenvironment of breast tissues. Breast cancer cells were cultured in hDAM scaffolds, and cell proliferation, migration, morphology, and drug responses were investigated. The growth profiles of multiple breast cancer cell lines cultured in hDAM scaffolds differed from the growth of those cultured on two-dimensional surfaces and more closely resembled the growth of xenografts. hDAM-cultured breast cancer cells also differed from those cultured on two-dimensional surfaces in terms of cell morphology, migration, expression of adhesion molecules, and sensitivity to drug treatment. Our results demonstrated that the hDAM system provides breast cancer cells with a biomimetic microenvironment in vitro that more closely mimics the in vivo microenvironment than existing two-dimensional and Matrigel three-dimensional cultures do, and thus can provide vital information for the characterization of cancer cells and screening of cancer therapeutics.

Little is known about the impact of hyperbaric oxygen treatment (HBOT) on matrix metalloproteinase (MMP) production in pre-existing high-oxidant wounds. This study aimed to investigate whether HBOT modulates reactive oxygen species (ROS) and MMP regulation in ischemic wound tissue. Using a validated ischemic wound model, Sprague-Dawley rats were divided into four groups for daily treatment: HBOT, N-acetylcysteine (NAC), HBO and NAC, and control (normoxia at sea level). High levels of inducible nitric oxide synthase (iNOS), gp91-phox, and 3-nitrotyrosine were detected in ischemic wounds, indicating high-oxidant stress. HBOT not only increased antioxidant enzyme expression, such as Cu/Zn-superoxide dismutase, catalase, and glutathione peroxidase, but also significantly decreased pro-oxidant enzyme levels, such as iNOS and gp91-phox, thereby decreasing net oxygen radical production by means of negative feedback. This effect was blocked by NAC treatment in ischemic wounds. HBO-treated ischemic wounds also manifested reduced phosphorylation of extracellular signal-regulated kinases 1/2, c-Jun N-terminal kinase, and c-Jun, indicating downregulation of mitogen-activated protein kinases (MAPKs). Furthermore, HBOT decreased the expression of several MMPs while simultaneously increasing tissue inhibitor of MMP (tissue inhibitor of metalloproteinase 2). These results indicate that HBOT acts via the ROS/MAPK/MMP signaling axis to reduce tissue degeneration and improve ischemic wound healing.

The authors have previously demonstrated promising results with tissue engineered trachea in vitro using decellularized matrix scaffolds. The present study aims to investigate the applicability of the construct in vivo.Tracheae harvested from Brown Norway rats (donor) and Lewis rats (recipient) were decellularized with repeated detergent-enzymatic treatment cycles. Decellularized Brown Norway tracheal matrix scaffolds were seeded with Lewis rat stem cell-derived chondrocytes externally and tracheal epithelial cells internally to generate a bilaminated tracheal construct. Brown Norway tracheal matrix scaffolds (n = 6), Lewis rat scaffolds (n = 6), and the engineered constructs (n = 3) were implanted subcutaneously in Lewis rats and observed for 4 weeks. Fresh Brown Norway (n = 6) and Lewis rat (n = 6) tracheae were implanted as controls. Histologic analysis for macrophage, CD8, and CD4 cell infiltration was performed.Allogeneic decellularized matrix scaffold showed significantly decreased macrophage, CD8+ and CD4+ cell infiltration compared with tracheal allografts, and demonstrated similar level of cell infiltration to syngeneic decellularized matrix scaffold. No significant differences in macrophage infiltration were observed between syngeneic decellularized matrix scaffolds and tracheal isografts. The engineered constructs achieved complete epithelial cell coverage and preserved lumen patency; however, chondrocytes failed to repopulate the cartilaginous matrix with statically seeding stem cell on scaffold.Decellularized tracheal matrix scaffold did not induce significant allograft rejection or foreign body reaction in vivo. Although the construct supported reepithelialization, stem cell-derived chondrocytes failed to engraft in the heterotopic environment and represent a focus of future investigations.

Using a perfusion decellularization protocol, we developed a decellularized skin/adipose tissue flap (DSAF) comprising extracellular matrix (ECM) and intact vasculature. Our DSAF had a dominant vascular pedicle, microcirculatory vascularity, and a sensory nerve network and retained three-dimensional (3D) nanofibrous structures well. DSAF, which was composed of collagen and laminin with well-preserved growth factors (e.g., vascular endothelial growth factor, basic fibroblast growth factor), was successfully repopulated with human adipose-derived stem cells (hASCs) and human umbilical vein endothelial cells (HUVECs), which integrated with DSAF and formed 3D aggregates and vessel-like structures in vitro . We used microsurgery techniques to re-anastomose the recellularized DSAF into nude rats. In vivo , the engineered flap construct underwent neovascularization and constructive remodeling, which was characterized by the predominant infiltration of M2 macrophages and significant adipose tissue formation at 3 months postoperatively. Our results indicate that DSAF co-cultured with hASCs and HUVECs is a promising platform for vascularized soft tissue flap engineering. This platform is not limited by the flap size, as the entire construct can be immediately perfused by the recellularized vascular network following simple re-integration into the host using conventional microsurgical techniques. Statement of Significance Significant soft tissue loss resulting from traumatic injury or tumor resection often requires surgical reconstruction using autologous soft tissue flaps. However, the limited availability of qualitative autologous flaps as well as the donor site morbidity significantly limits this approach. Engineered soft tissue flap grafts may offer a clinically relevant alternative to the autologous flap tissue. In this study, we engineered vascularized soft tissue free flap by using skin/adipose flap extracellular matrix scaffold (DSAF) in combination with multiple types of human cells. Following vascular reanastomosis in the recipient site, the engineered products successful regenerated large-scale fat tissue in vivo . This approach may provide a translatable platform for composite soft tissue free flap engineering for microsurgical reconstruction.

To compare cricothyroid membrane puncture directed tracheostomy (CMPDT) with conventional surgical tracheostomy (ST) and cricothyroidotomy (CT) and to evaluate the feasibility, efficacy and safety of this novel technique.15 minipigs were divided randomly into 3 groups, 5 in each. After general anesthesia, CMPDT, ST and CT were performed respectively according to the established techniques when SPO₂reached 80% (T0). Procedure duration, ECG and arterial blood gas results were recorded. Complications were recorded and scored according to an established score scale by an observer blinded to the grouping.Airway was successfully established in all animals (15/15). ECG monitor showed T-wave decreased and Q-T shortened after seasing of oxygen supply and both recovered rapidly to normal levels after reoxygenation. There were no significant differences between 3 groups in HR, BP, SPO2, SaO₂, PaO₂, PaCO₂and pH at pre-apnea, T0 or post-operation, but with significant intragroup variation in the parameters before and after operation. The time for CMPDT, ST and CT was (174 ± 34) s, (619 ± 128) s and (86 ± 12) s respectively. Three of 5 minipigs in ST group experienced hypotension due to longer time of hypoxia. 1 and one had minor bleeding and stoma infection after surgery. One of 5 animals in CT group had minor laryngeal cartilage injury leading to difficult decannulation, postoperative fiber bronchoscopy showed no subglottic stenosis. The complication scores were 13, 9, and 3 for ST, CT and CMPDT, respectively.All 3 methods can provide with effective airway access with no significant differences in ventilation effect, however CMPDT has short recovery time for SpO2 and other vital signs with the lowest complication score. The animal experiment suggests that CMPDT is a fast, safe and effective surgical technique for emergency airway.

The purpose of this study was to investigate the potential of silk fibroin and chitosan blend (SFCS) biological scaffolds for the purpose of cartilage tissue engineering with applications in tracheal tissue reconstruction. The capability of these scaffolds as cell carrier systems for chondrocytes was determined in vitro and cartilage generation in vivo on engineered chondrocyte-scaffold constructs with and without a perichondrium wrapping was tested in an in vivo nude mouse model. SFCS scaffolds supported chondrocyte adhesion, proliferation, and differentiation, determined as features of the cells based on the spherical cell morphology, increased accumulation of glycosaminoglycans, and increased collagen type II deposition with time within the scaffold framework. Perichondrium wrapping significantly (P

A multifaceted strategy using a composite of anti-cancer nanotherapeutic and natural biomaterials silk fibroin (SF) and chitosan (CS) blend scaffolds was investigated for the treatment of a tissue defect post-tumor resection by providing local release of the therapeutic and filling of the defect site with the regenerative bioscaffolds. The scaffold-emodin nanoparticle composites were fabricated and characterized for drug entrapment and release, mechanical strength, and efficacy against GILM2 breast cancer cells in vitro and in vivo in a rat tumor model. Emodin nanoparticles were embedded in SF and SFCS scaffolds and the amount of emodin entrapment was a function of the scaffold composition and emodin loading concentration. In vitro, there was a burst release of emodin from all scaffolds during the first 2 days though it was detected even after 24 days. Increase in emodin concentration in the scaffolds decreased the overall elastic modulus and ultimate tensile strength of the scaffolds. After 6 weeks of in vivo implantation, the cell density (p < 0.05) and percent degradation (p < 0.01) within the remodeled no emodin SFCS scaffold was significantly higher than the emodin loaded SFCS scaffolds, although there was no significant difference in the amount of collagen deposition in the regenerated SFCS scaffold. The presence and release of emodin from the SFCS scaffolds inhibited the integration of SFCS into the adjacent tumor due to the formation of an interfacial barrier of connective tissue that was lacking in emodin-free SFCS scaffolds. While no significant difference in tumor size was observed between the in vivo tested groups, tumors treated with emodin loaded SFCS scaffolds had decreased presence and size and similar regeneration of new tissue as compared to no emodin SFCS scaffolds.

The authors describe their experience with the use of the distally based dorsal pedal neurocutaneous flap for distal foot coverage. Ten patients underwent reconstruction with 13 flaps between 2004 and 2008. One patient suffered from a traffic accident and 9 from electrical injury. All of the soft tissue defects resulted in metatarsophalangeal joint and phalanx bone exposure. The size of the flaps ranged from 6 × 2 cm to 11 × 6 cm. The flaps were elevated based on intermediate or medial dorsal pedal nerves. Nine flaps were harvested in first stage to repair the distal foot. Among them, 3 showed partial necrosis in the distal region because of venous insufficiency. Four flaps underwent a surgical delay procedure in the first stage and were then transferred to reconstruct phalanx wounds in the second stage, surviving completely. All patients were satisfied with their reconstruction and donor site contour. The distally based dorsal pedal neurocutaneous flap can be used to repair the distal foot soft tissue defects, providing sufficient skin territory and excellent aesthetic and functional recovery. Surgical delay effectively enhances the distally based dorsal pedal neurocutaneous flap survival, particularly for the large size flaps.

The anterolateral thigh (ALT) flap has gained popularity, yet the donor site remains problematic. With increased knowledge of the vascular anatomy, we anticipated that we would be able to contour the ALT adipofascial flap when reconstructing facial deformities and micromastia without sacrificing skin at the donor site. A total of 24 cases of hemifacial atrophy and 1 case of micromastia underwent anterolateral thigh adipofascial flap transplantation with vascular anastomosis. All surgical reconstructions resulted in satisfactory results with minimal donor-site morbidity. The anterolateral thigh adipofascial perforator flap is an ideal choice for autologous tissue reconstruction with primary defatting.

The groin flap was designed to improve the conventional repair of the donor site of the anterolateral thigh flap. The modification method was applied successfully to cover the defects of donor sites of anterolateral thigh flaps in five patients. An ideal color match and a stable and completed composition for the donor sites were obtained. Little morbidity of the donor sites occurred. Cosmetic and functional rehabilitations of the donor sites were achieved. These results suggest the potential and novel method to improve the repair of the donor sites of anterolateral thigh flap.

Repair of soft tissue defects resulting from lumpectomy or mastectomy has become an important rehabilitation process for breast cancer patients. This study aimed to provide an adipose tissue engineering platform for soft tissue defect repair by combining decellularized human adipose tissue extracellular matrix (hDAM) and human adipose-derived stem cells (hASCs). To derive hDAM incised human adipose tissues underwent a decellularization process. Effective cell removal and lipid removal were proved by immunohistochemical analysis and DNA quantification. Scanning electron microscopic examination showed a three-dimensional nanofibrous architecture in hDAM. The hDAM included collagen, sulfated glycosaminoglycan, and vascular endothelial growth factor, but lacked major histocompatibility complex antigen I. hASC viability and proliferation on hDAM were proven in vitro. hDAM implanted subcutaneously in Fischer rats did not cause an immunogenic response, and it underwent remodeling, as indicated by host cell infiltration, neovascularization, and adipose tissue formation. Fresh fat grafts (Coleman technique) and engineered fat grafts (hDAM combined with hASCs) were implanted subcutaneously in nude rats. The implanted engineered fat grafts maintained their volume for 8 weeks, and the hASCs contributed to adipose tissue formation. In summary, the combination of hDAM and hASCs provides not only a clinically translatable platform for adipose tissue engineering, but also a vehicle for elucidating fat grafting mechanisms.

Ideal scaffolds that represent native extracellular matrix (ECM) properties of musculofascial tissues have great importance in musculofascial tissue engineering. However, detailed characterization of musculofascial tissues’ ECM (particularly, of fascia) from large animals is still lacking. In this study, we developed a decellularization protocol for processing pig composite musculofascial tissues. Decellularized muscle (D-muscle) and decellularized fascia (D-fascia), which are two important components of decellularized musculofascial extracellular matrix (DMM), were comprehensively characterized. D-muscle and D-fascia retained intact three-dimensional architecture, strong mechanical properties, and bioactivity of compositions such as collagen, laminin, glycosaminoglycan, and vascular endothelial growth factor. D-muscle and D-fascia provided a compatible niche for human adipose-derived stem cell integration and proliferation. Heterotopic and orthotopic implantation of D-muscle and D-fascia in a rodent model further proved their biocompatibility and myogenic properties during the remodeling process. The differing characteristics of D-muscle from D-fascia (e.g., D-muscle’s strong pro-angiogenic and pro-myogenic properties vs. D-fascia’s strong mechanical properties) indicate different clinical application opportunities of D-muscle vs. D-fascia scaffolds. DMM comprising muscle and fascia ECM as a whole unit can thus provide not only a clinically translatable platform for musculofascial tissue repair and regeneration but also a useful standard for scaffold design in musculofascial tissue engineering.

BACKGROUND: A tracheal matrix scaffold decellularized by detergent-enzymatic treatment has been shown as a promising scaffold in tracheal tissue engineering. The objectives of this study were to evaluate the impact of this technique on tracheal extracellular matrix integrity and characterize the matrix environment for recellularization. METHODS: Brown Norway rat tracheae were decellularized using a modified detergent-enzymatic treatment. Antigenicity and cellularity were monitored during processing. Glycosaminoglycan content, histoarchitecture, and mechanical properties were also evaluated. Matrix compatibility was determined by cytotoxicity assay. Surface ultrastructure of the matrix and its interaction with seeded bone marrow stem cell-derived chondrocytes and tracheal epithelial cells were examined by scanning electron microscopy. RESULTS: Rat trachea treated with five detergent-enzymatic treatment cycles demonstrated complete elimination of antigenicity. Although there was a significant loss of glycosaminoglycan (t test, p < 0.01), histoarchitecture of tracheal cartilage and basement membrane was retained after decellularization. Stiffness decreased, but sufficient compressive strength was preserved to maintain lumen patency. The decellularized matrix showed good cell compatibility and favored adhesion and growth of chondrocytes and respiratory epithelial cells, as demonstrated by scanning electron microscopy. CONCLUSIONS: At the point of complete antigen removal, detergent-enzymatic treatment altered tracheal extracellular matrix composition but preserved the major structure and adequate mechanical strength. The matrix provided a compatible and supportive environment for recellularization.

The purpose of this article is to describe the author's experience using the anterolateral thigh (ALT) flap for the reconstruction of a variety of soft tissue defects. The flap utility and donor site morbidity were evaluated in 126 cases from March 1985 to August 2007. The ALT flaps were harvested as either free fasciocutaneous, free adipofascial, fasciocutaneous island, or reversed fasciocutaneous island flaps to repair facial, neck, breast, trunk, and extremity defects. In 40 cases (32%), the skin vessels were found to be septocutaneous perforators, and in 86 cases (68%), they were found as musculocutaneous perforators. Of the 126 flaps, 121 survived completely, providing a success rate of 96.0%. There were four cases undergoing multidetector-row computed tomographic angiography (CTA) for preoperative perforator mapping, and all perforators were confirmed intraoperatively. In conclusion, the ALT flap is a versatile and reliable flap that could well be a priority option for soft tissue reconstruction. CTA can provide more valuable and accurate anatomic information about the pedicle and perforators, making it safer and faster to harvest a targeted ALT perforator flap with less donor site morbidity.