Efficacy of Superselective Intra-arterial Recanalization of Embolized Arteries Resulting from Facial Hyaluronic Acid Injection.

BACKGROUND: Arterial embolism is a rare complication caused by hyaluronic acid (HA) injection. However, it is one of the most serious complications. Once it happens, the complication would have a great and long-term impact on patients. Intra-arterial recanalization has been reported for recovering the visual acuity in patients with visual loss caused by hyaluronic acid. There is little report about the benefits of superselective intra-arterial recanalization therapy for skin wounds caused by hyaluronic acid vascular embolization. METHODS: Eight patients who had received the superselective intra-arterial recanalization therapy were retrospectively reviewed. Hyaluronidase was injected into the facial artery by superselective intra-arterial recanalization therapy, followed by symptomatic treatment. The facial artery recanalization was successfully performed and no interventional procedure-related adverse events happened. RESULTS: Arterial embolization accompanies by the interruption or reduction of blood supply, followed by ochrodermia, pain, numbness, swelling, yellowish white secreta and even necrosis on skin wound area. Early detection of skin blood supply disorders and early recovery of blood supply are very critical to treat facial artery embolization caused by HA. After superselective intra-arterial recanalization therapy, the blood supply to facial skin was restored and skin wounds recovered in all patients. Only 1 patient was left with small and superficial scars. CONCLUSION: Superselective intra-arterial recanalization therapy is an effective and safe method that can alleviate skin wounds caused by HA vascular embolization. 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 .

Percutaneous Intra-arterial Hyaluronidase Injection for Hyaluronic Acid Filler Embolism Threatening Skin Barrier Integrity: Implementation of a Stepwise Treatment Protocol.

BACKGROUND: Hyaluronic acid (HA) filler-induced vascular embolism that threatens skin integrity is an urgent situation. There is increasing evidence that percutaneous intra-arterial hyaluronidase injection is an effective therapeutic technique for it. However, until now, there is a lack of a unifying protocol about the technique. OBJECTIVES: This study aims to provide a conclusion of percutaneous intra-arterial hyaluronidase injection along with adjunctive measures on the treatment of occlusions precipitated by HA-based filler and develop a stepwise treatment protocol. METHODS: We searched PubMed for peer-reviewed studies, consensus statements, case series, and case reports using a variety of keywords. RESULTS: High-dose, pulsed hyaluronidase is the mainstay for the treatment of HA filler-induced embolism, but percutaneous intra-arterial hyaluronidase injection is a more effective technique. Until now, hyaluronidase is injected into three arteries percutaneously, including facial artery, supratrochlear artery, and superficial temporal artery. Furthermore, the adjunctive measures that may optimize clearance of an occlusion and/or skin barrier repair such as the use of image guidance and CGF should be considered. CONCLUSION: Vascular occlusions that threaten skin integrity are an urgent matter which requires accurate diagnosis and effective intervention. Percutaneous intra-arterial hyaluronidase injection along with adjunctive measures performed in a stepwise manner is key to an optimal outcome. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

CCN1 secreted by human adipose-derived stem cells enhances wound healing and promotes angiogenesis through activating the AKT signalling pathway.

The study aimed to explore the role of cellular communication network factor 1 (CCN1) an extracellular matrix protein in hADSC-treated wound healing. Immunofluorescence and enzyme-linked immunosorbent assays (ELISA) were used to demonstrate the secretion of CCN1 by hADSCs, isolated from human fat tissue. We investigated the role of CCN1 in wound healing by knockdown of CCN1 expression in hADSCs using CCN1 siRNA. Conditioned medium of hADSCs or hADSCs with CCN1 knocked down (hADSC-CMCCN1↓ ) was collected. After treatment with plain DMEM/F12, hADSC-CM, hADSC-CMCCN1↓ , or recombinant human CCN1 (rhCCN1), the wound healing abilities of human umbilical vascular endothelial cells (HUVECs) were assayed, and the AKT, also known as protein kinase B (PKB), signalling pathway was detected using western blotting. Next, we created full-thickness skin wounds on the backs of the mice and different treatments were applied to the wound surface. Wound size was measured using a digital camera on days 0-10, and evaluated. H&E and immunohistochemical staining were performed, and laser Doppler perfusion imaging was used to evaluate blood perfusion. The wound model and wound-healing assay showed that the hADSCs-CM and rhCCN1 groups had enhanced wound healing compared to the hADSCs-CMCCN1↓ group. Further, CCN1 and hADSCs-CM promoted the proliferation and migration of HUVECs through the AKT signalling pathway. We concluded that CCN1 secreted by hADSCs enhances wound healing and promotes angiogenesis by activating the AKT signalling pathway. CCN1 plays a vital role in the regulation of hADSCs-CM during wound healing.

Splint-free line drawing model: An innovative method for excisional wound models.

The physiological phenomenon of wound contraction in mice cannot completely imitate the process of human skin regeneration, which is primarily attributed to reepithelialisation. As such, excisional wound models in mice are considered to be imperfect comparisons. This study aimed to enhance the correlation of mouse excisional wound models with that of humans, and to offer more practical and accurate ways to record and measure wound areas. We present evidence that simple excisional wounds produce a robust and stable wound model by comparing splint-free and splint groups. We monitored reepithelialisation and contraction in the C57BL/6J mouse excision wound model at different time points and prove that excisional wounds heal by both contraction and reepithelialisation. Some parameters were measured and a formula was used to calculate the area of wound reepithelialisation and contraction. In our results, reepithelialisation accounted for 46% of the wound closure of full-thickness excisional wounds. In conclusion, excisional wound models can be used as wound-healing models and a straightforward formula may be used to determine the process of reepithelialisation over a wound bed created by a simple excisional rodent wound model.

Thermal drift correction method for laboratory nanocomputed tomography based on global mixed evaluation.

Nanocomputed tomography (nanoCT) is an effective tool for the nondestructive observation of 3D structures of nanomaterials; however, it requires additional correction phantom to reduce artifacts induced by the focal drift of the X-ray source and mechanical thermal expansion. Drift correction without a correction phantom typically uses rapidly acquired sparse projections to align the original projections. The noise and brightness difference in the projections limit the accuracy of existing feature-based methods such as locality preserving matching (LPM) and random sample consensus (RANSAC). Herein, a rough-to-refined correction framework based on global mixed evaluation (GME) is proposed for precise drift estimation. First, a new evaluation criterion for projection alignment, named GME, which comprises the structural similarity (SSIM) index and average phase difference (APD), is designed. Subsequently, an accurate projection alignment is achieved to estimate the drift by optimizing the GME within the proposed correction framework based on the rough-to-refined outlier elimination strategy. The simulated 2D projection alignment experiments show that the accuracy of the GME is improved by 14× and 12× than that of the mainstream feature-based methods LPM and RANSAC, respectively. The proposed method is validated through actual 3D imaging experiments.

Spatial correlation between electricity generation and economic scale in Africa.

This study attempts to determine whether there is a spatial correlation between electricity generation and economic scale promoting coordinated development in Africa. We explore the spatial similarity and gray correlation degree between electricity generation and economic scale in Africa since the 21st century by adopting barycenter coupling and Gray Correlation Analysis method. We argue that there is a strong correlation between electricity generation and economic scale. Our findings indicate a significant spatial difference in electricity generation, mainly concentrated in Northern and Southern Africa. Furthermore, spatial pattern remains largely consistent over time, mirroring trends observed at the economic scale. Electricity generation and economic scale were concentrated in six countries- South Africa, Egypt, Algeria, Nigeria, Morocco, and Libya- and did not change significantly over time. A correlation analysis between electricity generation and the economic scale further confirmed this, with a linear coefficient of 0.907. Both the gravity centers of economic scale and electricity generation in Africa move farther in the north-south direction than in the East-West direction, with the former showing a Southwest-Northeast-Southwest track feature and the latter a Northeast-Southwest track feature. The spatial distribution of the gravity centers of electricity generation and the gravity centers of the economic scale in Africa are highly consistent; electricity generation highly correlates with the economic scale, consistent with the research conclusion obtained by the Gray Correlation Analysis method. This study suggests the coordinated development of electricity generation and economic scales in various African countries.

Skin and soft tissue infection of Nontuberculous mycobacterium after injection lipolysis.

BACKGROUND: Injection lipolysis is used for body and face contouring due to its minimal invasiveness and cost-effectiveness, but related complications such as nontuberculous mycobacterium infection significantly affect its clinical application. AIMS: This study aimed to review the literature on NTM infection after injection lipolysis. METHODS: We conducted a literature review of scientific journals published in Medline and PubMed up to September 2022 on patients with NTM skin and soft tissue infections. We used the keywords: nontuberculous mycobacterium, infection, injection lipolysis, and lipolytic solution in various combinations with the Boolean operators AND, OR, and NOT. Only articles available in English and full version publications were considered for this review. Here, we reviewed the relevant mechanisms and drugs for injectable lipolysis and analyzed the possible correlation between NTM infection and injection lipolysis. We also summarize methods for the diagnosis and treatment of NTM infections and present some perspectives on this therapy. RESULTS: Many patients with NTM infections had a history of fat-related surgery or therapy. NTM infection after injection lipolysis may be related to inadequate disinfection and sterilization of injection equipment and clinical procedures, the unqualified medication itself and free fatty acids released during injection lipolysis. Currently, diagnosis and treatment of NTM infection after lipolysis injections remains challenging. CONCLUSIONS: Injection lipolysis represents a helpful option for local fat reduction. Doctors should strictly abide by the aseptic operation standards and use qualified products for there is a correlation between skin and soft tissue infection of nontuberculous mycobacterium and injection lipolysis. Providers should understand the mechanism, indications, and associated risks of injection lipolysis when injecting fat-dissolving drugs to reduce localized fat.

3D-bioprinted human lipoaspirate-derived cell-laden skin constructs for healing of full-thickness skin defects.

29Three-dimensional (3D)-printed bioactive scaffolds that can be produced rapidly could offer an individualized approach for treating full-thickness skin defects. Decellularized extracellular matrix (dECM) and mesenchymal stem cells have been proven to support wound healing. Adipose tissues obtained by liposuction are rich in adipose-derived dECM (adECM) and adipose-derived stem cells (ADSCs) and thus represent a natural source of bioactive materials for 3D bioprinting. Herein, ADSC-laden 3D-printed bioactive scaffolds consisting of gelatin methacryloyl (GelMA), hyaluronic acid methacryloyl (HAMA), and adECM were fabricated with dual properties of photocrosslinking in vitro and thermosensitive crosslinking in vivo. adECM was prepared by decellularization of human lipoaspirate and mixed as a bioactive material with GelMA and HAMA to form a bioink. Compared with the GelMA-HAMA bioink, the adECM-GelMA-HAMA bioink had better wettability, degradability, and cytocompatibility. Full-thickness skin defect healing in a nude mouse model showed that ADSC-laden adECM-GelMA-HAMA scaffolds accelerated wound healing by promoting faster neovascularization, collagen secretion, and remodeling. ADSCs and adECM collectively conferred bioactivity on the prepared bioink. This study represents a novel approach to enhancing the biological activity of 3D-bioprinted skin substitutes by adding adECM and ADSCs derived from human lipoaspirate and may provide a promising therapeutic option for full-thickness skin defects.

3D-Bioprinted Biomimetic Multilayer Implants Comprising Microfragmented Adipose Extracellular Matrix and Cells Improve Wound Healing in a Murine Model of Full-Thickness Skin Defects.

Repairing full-thickness skin defects is a major challenge in clinical practice. Three-dimensional (3D) bioprinting of living cells and biomaterials is a promising technique to resolve this challenge. However, the time-consuming preparation and limited sources of biomaterials are bottlenecks that must be addressed. Therefore, we developed a simple and fast method to directly process adipose tissue into a microfragmented adipose extracellular matrix (mFAECM) as the main component of bioink to fabricate 3D-bioprinted, biomimetic, multilayer implants. The mFAECM retained most of the collagen and sulfated glycosaminoglycans in the native tissue. In vitro, the mFAECM composite demonstrated biocompatibility, printability, and fidelity and could support cell adhesion. In a full-thickness skin defect model in nude mice, cells encapsulated in the implant survived and participated in wound repair after implantation. The basic structures of the implant were maintained throughout wound healing and gradually metabolized. The biomimetic multilayer implants fabricated via mFAECM composite bioinks and cells could accelerate wound healing by promoting the contraction of new tissue inside the wound, collagen secretion and remodeling, and neovascularization. This study provides an approach for improving the timeliness of fabricating 3D-bioprinted skin substitutes and may offer a useful tool for treating full-thickness skin defects.

Spatio-Temporal Coupling Evolution of Urbanisation and Carbon Emission in the Yangtze River Economic Belt.

The distribution characteristics of urbanisation level and per capita carbon emissions from 2006 to 2019 were investigated by the ranking scale rule, using 108 cities in the Yangtze River Economic Belt of China. A coupling coordination model was established to analyse the relative development relationship between the two, and exploratory spatial-temporal data analysis (ESTDA) was applied to reveal the spatial interaction characteristics and temporal evolution pattern of the coupling coordination degree. The results demonstrate that: (1) The urbanisation level and per capita carbon emissions of the Yangtze River Economic Belt show a stable spatial structure of 'high in the east and low in the west'. (2) The coupling and coordination degree of urbanisation level and carbon emissions show a trend of 'decreasing and then increasing', with a spatial distribution of 'high in the east and low in the west'. (3) The spatial structure exhibits strong stability, dependence, and integration. The stability is enhanced from west to east, the coupling coordination degree has strong transfer inertia, and the spatial pattern's path dependence and locking characteristics show a trend of weak fluctuation. Therefore, the coupling and coordination analysis is required for the coordinated development of urbanisation and carbon emission reduction.

Application of 3D-printed tissue-engineered skin substitute using innovative biomaterial loaded with human adipose-derived stem cells in wound healing.

Large-scale skin injuries are usually accompanied by impaired wound healing, resulting in scar formation, or significant morbidity and mortality. The aim of this study is to explore the in vivo application of 3D-printed tissue-engineered skin substitute using innovative biomaterial loaded with human adipose-derived stem cells (hADSCs) in wound healing. Adipose tissue was decellularized, and extracellular matrix components were lyophilized and solubilized to obtain adipose tissue decellularized extracellular matrix (dECM) pre-gel. The newly designed biomaterial is composed of adipose tissue dECM pre-gel, methacrylated gelatin (GelMA), and methacrylated hyaluronic acid (HAMA). Rheological measurement was performed to evaluate the phase-transition temperature and the storage and loss modulus at this temperature. Tissue-engineered skin substitute loaded with hADSCs was fabricated by 3D printing. We used nude mice to establish full-thickness skin wound healing model and divided them into four groups randomly: (A) Full-thickness skin graft treatment group, (B) 3D-bioprinted skin substitute treatment group as the experimental group, (C) microskin graft treatment group, and (D) control group. The amount of DNA in each milligram of dECM was 24.5 ± 7.1 ng, fulfilling the currently accepted decellularization criteria. The solubilized adipose tissue dECM was thermo-sensitive biomaterial and underwent a sol-gel phase transition when temperature rises. The dECM-GelMA-HAMA precursor undergoes a gel-sol phase transition at 17.5°C, where the storage and loss modulus of the precursor is about 8 Pa. The scanning electron microscope showed that the interior of crosslinked dECM-GelMA-HAMA hydrogel is 3D porous network structure with suitable porosity and pore size. The shape of the skin substitute is stable with regular grid-like scaffold structure. Wound healing in the experimented animals was accelerated after being treated with 3D-printed skin substitute, which attenuate inflammatory response, increase blood perfusion around the wound, as well as promote re-epithelialization, collagen deposition and alignment, and angiogenesis. In summary, 3D-printed dECM-GelMA-HAMA tissue-engineered skin substitute loaded with hADSCs, which can be fabricated by 3D printing, can accelerate wound healing and improve healing quality by promoting angiogenesis. The hADSCs and the stable 3D-printed stereoscopic grid-like scaffold structure play a critical role in promoting wound healing.

Metrological characterization of porosity graded ß-Ti21S triply periodic minimal surface cellular structure manufactured by laser powder bed fusion.

The design of a functionally graded porous structure (FGPS) for use in prosthetic devices is crucial for meeting both mechanical and biological requirements. One of the most commonly used cellular structures in FGPS is the triply periodic minimal surface (TPMS) structure due to its ability to be defined by implicit equations, which allows for smooth transitions between layers. This study evaluates the feasibility of using a novel ß-Ti21S alloy to fabricate TPMS-based FGPS. This beta titanium alloy exhibits low elastic modulus (53 GPa) and good mechanical properties in as-built condition. Two TPMS FGPSs with relative density gradients of 0.17, 0.34, 0.50, 0.66, and 0.83 and unit cell sizes of 2.5 mm and 4 mm were designed and fabricated using laser powder bed fusion (LPBF). The as-manufactured structures were analyzed using scanning electron microscopy (SEM) and X-ray micro-computed tomography (µ-CT), and the results were compared to the design. The analysis revealed that the pore size and ligament thickness were undersized by less than 5%. Compression tests showed that the stabilized elastic modulus was 4.1 GPa for the TPMS with a 2.5 mm unit cell size and 10.7 GPa for the TPMS with a 4 mm unit cell size. A finite element simulation was performed to predict the specimen's elastic properties, and a lumped model based on lattice homogenized properties was proposed and its limitations were explored.

STEDNet: Swin transformer-based encoder-decoder network for noise reduction in low-dose CT.

BACKGROUND: Low-dose computed tomography (LDCT) can reduce the dose of X-ray radiation, making it increasingly significant for routine clinical diagnosis and treatment planning. However, the noise introduced by low-dose X-ray exposure degrades the quality of CT images, affecting the accuracy of clinical diagnosis. Purpose The noises, artifacts, and high-frequency components are similarly distributed in LDCT images. Transformer can capture global context information in an attentional manner to create distant dependencies on targets and extract more powerful features. In this paper, we reduce the impact of image errors on the ability to retain detailed information and improve the noise suppression performance by fully mining the distribution characteristics of image information. METHODS: This paper proposed an LDCT noise and artifact suppressing network based on Swin Transformer. The network includes a noise extraction sub-network and a noise removal sub-network. The noise extraction and removal capability are improved using a coarse extraction network of high-frequency features based on full convolution. The noise removal sub-network improves the network's ability to extract relevant image features by using a Swin Transformer with a shift window as an encoder-decoder and skip connections for global feature fusion. Also, the perceptual field is extended by extracting multi-scale features of the images to recover the spatial resolution of the feature maps. The network uses a loss constraint with a combination of L1 and MS-SSIM to improve and ensure the stability and denoising effect of the network. RESULTS: The denoising ability and clinical applicability of the methods were tested using clinical datasets. Compared with DnCNN, RED-CNN, CBDNet and TSCN, the STEDNet method shows a better denoising effect on RMSE and PSNR. The STEDNet method effectively removes image noise and preserves the image structure to the maximum extent, making the reconstructed image closest to the NDCT image. The subjective and objective analysis of several sets of experiments shows that the method in this paper can effectively maintain the structure, edges, and textures of the denoised images while having good noise suppression performance. In the real data evaluation, the RMSE of this method is reduced by 18.82%, 15.15%, 2.25%, and 1.10% on average compared with DnCNN, RED-CNN, CBDNet, and TSCNN, respectively. The average improvement of PSNR is 9.53%, 7.33%, 2.65%, and 3.69%, respectively. CONCLUSIONS: This paper proposed a LDCT image denoising algorithm based on end-to-end training. The method in this paper can effectively improve the diagnostic performance of CT images by constraining the details of the images and restoring the LDCT image structure. The problem of increased noise and artifacts in CT images can be solved while maintaining the integrity of CT image tissue structure and pathological information. Compared with other algorithms, this method has better denoising effects both quantitatively and qualitatively.