Ischemic Skin Research Articles

Engineering exosomes from fibroblast growth factor 1 pre-conditioned adipose-derived stem cells promote ischemic skin flaps survival by activating autophagy

BackgroundThe recovery of ischemic skin flaps is a major concern in clinical settings. The purpose of this study is to evaluate the effects of engineered exosomes derived from FGF1 pre-conditioned adipose-derived stem cells (FEXO) on ischemic skin flaps. Method6 patients who suffered from pressure ulcer at stage 4 and underwent skin flaps surgery were recruited in this study to screen the potential targets of ischemic skin flaps in FGF family. FGF1 was co-incubated with adipose stem cells, and ultracentrifugation was applied to extract FEXO. Transcriptome sequencing analysis was used to determine the most effective microRNA in FEXO. Animal skin flaps models were established in our study to verify the effects of FEXO. Immunofluorescence (IF), western blotting (WB) and other molecular strategy were used to evaluate the effects and mechanism of FEXO. ResultsFGF1 was expected to be the therapeutic and diagnostic target of ischemic skin flaps, but there is still some deficiency in rescuing skin flaps. FEXO significantly improved the viability of RPSFs and endothelial cells by inhibiting oxidative stress and alleviating apoptosis and pyroptosis through augmenting autophagy flux. In addition, FEXO inhibited the over-activated inflammation responses. Transcriptome sequencing analysis showed that miR-183-5p was significantly elevated in FEXO, and inhibiting miR-183-5p resulted in impaired protective effects of autophagy in skin flaps. The exosomal miR-183-5p markedly enhanced cell viability, inhibited oxidative stress and alleviated apoptosis and pyroptosis in endothelial cells by targeting GPR137 through Pi3k/Akt/mTOR pathway, indicating that GPR137 could also be a therapeutic target of ischemic skin flap. It was also notabale that FGF1 increased the number of exosomes by upregulating VAMP3, which may be a promising strategy for clinical translation. ConclusionFEXO markedly improved the survivial rate of ischemic skin flaps through miR-183-5p/GPR137/Pi3k/Akt/mTOR axis, which would be a promising strategy to rescue ischemic skin flaps.

Effect of ultrahigh frequency ozone therapy on oxidative metabolism in the blood of rats with ischemic skin flaps: A preclinical experimental randomized study

Background. Maintaining and restoring skin microcirculation in surgical flaps, as well as accelerating rehabilitation after skin flap transplantation, in order to mitigate the consequences of burns and injuries, remain a pressing issue. In addition to various timings and techniques for plastic surgery, physiotherapeutic approaches prove to be efficient and include low-intensity electromagnetic radiation in millimeter waves as their prominent techniques. In recent years, experts have paid an increasing attention to the application of low-intensity electromagnetic radiation across different frequency ranges for the enhancement of microcirculation in patients after surgical correction of burn consequences. However, this approach is yet to be further validated. Objective. To investigate the effect of different combinations of ultrahigh frequency electromagnetic radiation with ozone therapy on the oxidative metabolism of blood in rats using a model of ischemic skin flaps. Methods. A preclinical experimental randomized study was conducted on 100 adult male Wistar rats weighing between 200 and 250 grams. Five equal-sized groups of animals were formed in the study: Group 1: intact (no interventions), and Groups 2, 3, 4, and 5: after surgical intervention (modeling of ischemic skin flaps). Animals in Group 2 (control group) received no therapeutic procedures. Rats in Groups 3 and 5 underwent a 10-minute course of electromagnetic radiation exposure with a dose of 0.06 mJ for seven days. Animals in Group 3 were exposed to electromagnetic radiation of ultrahigh frequency with a range of 53–78 GHz. Animals in Group 4 received injections of ozonized saline solution (with a saturating ozone concentration in the ozonized oxygen mixture of 3000 µg/L) daily for 7 days, administered intraperitoneally at a volume of 1 mL. Group 5 underwent a combined treatment: daily exposure to ultrahigh frequency electromagnetic radiation along with intraperitoneal ozone therapy (the application modalities of these treatments were similar to those used in Groups 3 and 4, respectively). The intensity of lipid peroxidation, peroxide resistance in erythrocytes, and overall antioxidant system activity were assessed in order to investigate the balance of pro- and antioxidant systems in plasma and erythrocytes. Additionally, the study involved determination of the level of malondialdehyde content and evaluation of the activity of superoxide dismutase and catalase in erythrocytes. The obtained date were analyzed, using MS Office 2013 (Microsoft Corporation, USA) and Statistica 10 (StatSoft, USA). Results. The conducted analysis revealed an antioxidant effect from ultrahigh frequency electromagnetic radiation, with this effect being enhanced by ozone therapy. In addition, the study detected the inhibition of free radical oxidation under the ultrahigh frequency electromagnetic radiation and ozone therapy. Conclusion. Thus, the positive effects of the studied therapeutic factors manifest at the systemic level, as evidenced by the optimization of biochemical parameters and indicators of oxidative metabolism in the plasma of animal blood. It has been established that ultrahigh frequency electromagnetic radiation, administered in a noise mode, exerts a regulatory effect on pro- and antioxidant systems in the body, as demonstrated in a model of transplanted skin flap. This intervention leads to a reduction in the severity of oxidative stress and an enhancement of antioxidant reserves in the blood. The observed effect is further amplified with the additional application of ozone therapy.

A-282 Purpura fulminans caused by Haemophilus influenzae: case report of unusual etiology

Abstract Background Fulminant purpura is a clinical syndrome characterized by a purplish, ischemic-looking skin rash, commonly accompanied by systemic symptoms ranging from acute febrile syndrome to septic shock. Due to high lethality of possible infectious etiologies, immediate recognition and early initiation of empirical antimicrobial therapy are crucial to ensure better outcomes. Interdisciplinary collaboration among healthcare teams, infectious disease specialists and microbiologists is essential to ensure accurate and early microbiological diagnosis. Methods This work aims to report a case of Haemophilus influenzae-induced purpura fulminans that occurred in Fortaleza-CE, a coastal city in northeastern Brazil, highlighting clinical recognition and microbiological identification, based on review of medical records. Results Case report A 59-year-old man, originally from Germany, was on vacation in Brazil. He presented to emergency medical service with an acute onset of fever, abdominal pain and diarrhea, progressing to decreased level of consciousness and purplish ischemic skin lesions with hemorrhagic bullae on trunk and extremities (Figure 1), with no history of trauma. Upon admission, the blood exams showed bicytopenia - 1900 leukocytes/µL (86% segmented) and 51,000 platelets/µL - and very high C-reactive protein (41.58 mg/dL). Although empirical antimicrobial therapy with vancomycin and piperacillin-tazobactam was initiated, patient progressed to septic shock, hepatic dysfunction, requiring mechanical ventilation, vasopressor support, and renal replacement therapy. Blood cultures from hospital admission were positive after about 14 hours and allowed isolation of small and translucent colonies in Chocolate PVX plate Agar (BioMerieux™). Maldi tof analysis by Vitek MS identified H. influenzae (99.9 % accuracy). Despite prolonged hospitalization due to multiple organ dysfunctions, patient had a positive outcome. Conclusions This case illustrates the importance of immediate recognition of the syndrome coupled with assertive empirical treatment and early microbiological diagnosis for a positive clinical outcome, even in a severe presentation. Multiprofessional approach is essential for accurate and early diagnosis.

Terlipressin-induced skin necrosis in cirrhotic patients-A case report and comprehensive literature review.

The occurrence of terlipressin-induced skin necrosis in cirrhotic patients is a rare but serious adverse event that warrants further investigation. Clinicians should be aware of this potential complication in cirrhotic patients receiving terlipressin therapy and closely monitor for any signs of skin necrosis. Early recognition and prompt intervention are crucial in preventing further complications and improving patient outcomes. Further research is needed to better understand the risk factors associated with terlipressin-induced skin necrosis and to develop effective preventive strategies. Overall, healthcare providers should exercise caution when prescribing terlipressin to cirrhotic patients, weighing the potential benefits against the risks of this rare but significant adverse event. Terlipressin is commonly used to manage conditions related to portal hypertension, such as hepatorenal syndrome and esophageal variceal bleeding. Despite its therapeutic benefits, terlipressin can rarely lead to severe ischemic complications involving the skin vasculature, known as terlipressin-induced skin necrosis. We present a 50-year-old male with cirrhosis and acute variceal bleeding who developed skin necrosis following terlipressin administration. We performed a comprehensive review of the literature by analyzing 18 case reports/case series comprising 22 cirrhotic patients with terlipressin-induced skin necrosis. Among these individuals, we found a mean age of 51 years with a male predominance (78%). Further analysis showed that the onset of skin necrosis ranged from 2 to 5 days post-terlipressin initiation, with bolus administration being predominant (85.7%). The underlying pathophysiological mechanisms of terlipressin-induced skin ischemia are still elusive but primarily attributed to the vasoconstrictive and thrombogenic effects. Management involves terlipressin discontinuation and supportive care. Physicians should be aware of this potential complication in patients receiving terlipressin and closely observe for any signs of skin rash.

Local Treatment of Ischemic Skin Wounds Using a Unique Drug Mixture in Combination with Magnetic Therapy

Local Treatment of Ischemic Skin Wounds Using a Unique Drug Mixture in Combination with Magnetic Therapy

The Impact of Gel Parameters on the Dispersal and Fragmentation of Hyaluronic Acid Gel Fillers within an Artificial Model of Arterial Embolism.

Accidental arterial embolization of hyaluronic acid (HA) fillers can lead to severe complications, including skin ischemia, blindness, and stroke. Currently, the intra-arterial dispersal and fragmentation behavior of HA gels is unknown but critical to our understanding of the pathomechanism of these injuries. This work introduces the Pulsatile Unit for the Laboratory Simulation of Arterio-embolic Restrictions (PULSAR) and evaluates the intravascular behavior of different HA gels. The fragmentation and dispersal behaviors of four HA gels with distinct rheological properties were evaluated via high-resolution videography and ImageJ particle size and morphology analysis. The gels' elastic modulus (G'), loss modulus (G″), tan(δ), and HA concentration were subsequently correlated with their intra-arterial behaviors. This study effectively confirms the extensive fragmentation of HA gels upon arterial inoculation, with particle sizes ranging from <50 µm to >1 mm. Gel particle size and morphology correlated most significantly with tan(δ). Conversely, arterial flow rates did not significantly influence gel fragmentation behavior, though the probability of proximal, macrovascular obstruction was affected. Overall, this study validates the PULSAR model for simulation of arterial dynamics and the testing of intravascular filler kinematics. The findings demonstrate the ability of gels to microfragment and disseminate distally, as well as induce partial proximal occlusion depending on gel rheology and arterial flow parameters.

A case of Buerger's disease with vasculopathy and skin fibrosis requiring differential diagnosis from systemic sclerosis.

Buerger's disease is characterized by peripheral ischemia due to occlusion of small- and medium-sized arteries in the extremities. This report describes a case of Buerger's disease in a 51-year-old male who presented with findings resembling systemic sclerosis. The patient exhibited Raynaud's phenomenon in year X-3, which developed to skin hardening, nail avulsion, and ulceration of the right fingers in year X. Diagnostic testing showed positive microvasculopathy on nailfold videocapillaroscopy (NVC) and positive fibrosis on skin biopsy. Although the patient fulfilled the 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for systemic sclerosis, several findings in this case were atypical for systemic sclerosis, including left-right asymmetry in finger involvement, nail loss, and negative autoantibody tests. Contrast-enhanced computed tomography showed poor perfusion of the right ulnar artery, and a heavy smoking history was established in the patient case. Therefore, based on Shionoya's criteria, he was diagnosed with a case of Buerger's disease confined to the upper extremity. Smoking cessation and vasodilator therapy resulted in the prompt resolution of ischemic symptoms, skin hardening, and ulcerations. Furthermore, NVC abnormalities improved, and ulnar artery occlusion showed reperfusion on repeat testing. The present case suggests that hypoxemia-driven microvasculopathy may contribute to vascular occlusion and skin fibrosis observed in this atypical presentation.

Aesthetic Reconstruction of the Sequelae of Large Facial Involuted Infantile Hemangioma with Tissue Expanders.

Large involuted infantile hemangioma remains a challenge in facial reconstruction. The characteristic fibrofatty residuum and multiple subunits/tissues involvement contribute significantly to the difficulty of surgical management. Tissue expander plays an important role in facial reconstruction, allowing plastic surgeons to repair skin damaged by both congenital and acquired defects. Between 2009 and 2021, 30 patients who underwent tissue expansion surgery were reviewed in a single hospital. The demographic data, lesion characteristics, surgical approaches, complication rate, and aesthetic outcomes were analyzed. Thirty patients (5 men and 25 women) with a mean age of 14.03 ± 7.25 years (range, 4-33years) were included. The mean follow-up is 35.92months, ranging from 9 to 75months. Tissue expansion-related complications include closed infection, 2/30 (6.67%); skin ischemia, 2/30 (6.67%); hematoma, 1/30 (3.33%); flap necrosis, 1/30 (3.33%). Large facial involuted infantile hemangiomas have variable patterns of presentation and necessitate tailored therapy. Tissue expansion is a reproducible approach to achieving aesthetic reconstruction. 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 .

Evaluating the pro-survival potential of apoptotic bodies derived from 2D- and 3D- cultured adipose stem cells in ischaemic flaps

In the realm of large-area trauma flap transplantation, averting ischaemic necrosis emerges as a pivotal concern. Several key mechanisms, including the promotion of angiogenesis, the inhibition of oxidative stress, the suppression of cell death, and the mitigation of inflammation, are crucial for enhancing skin flap survival. Apoptotic bodies (ABs), arising from cell apoptosis, have recently emerged as significant contributors to these functions. This study engineered three-dimensional (3D)-ABs using tissue-like mouse adipose-derived stem cells (mADSCs) cultured in a 3D environment to compare their superior biological effects against 2D-ABs in bolstering skin flap survival. The findings reveal that 3D-ABs (85.74 ± 4.51) % outperform 2D-ABs (76.48 ± 5.04) % in enhancing the survival rate of ischaemic skin flaps (60.45 ± 8.95) % (all p < 0.05). Mechanistically, they stimulated angiogenesis, mitigated oxidative stress, suppressed apoptosis, and facilitated the transition of macrophages from M1 to M2 polarization (all p < 0.05). A comparative analysis of microRNA (miRNA) profiles in 3D- and 2D-ABs identified several specific miRNAs (miR-423-5p-up, miR30b-5p-down, etc.) with pertinent roles. In summary, ABs derived from mADSCs cultured in a 3D spheroid-like arrangement exhibit heightened biological activity compared to those from 2D-cultured mADSCs and are more effective in promoting ischaemic skin flap survival. These effects are attributed to their influence on specific miRNAs.

A novel intervention for wound bed preparation in severe extremity trauma: Highly concentrated carbon dioxide bathing

IntroductionIn severe extremity trauma involving large tissue defects, early closure (e.g., free-flap surgery) of the defects is an essential step for good functional reconstruction; however, in some cases, early closure may be difficult. Highly concentrated carbon dioxide bathing, used to improve blood flow in ischemic limbs and skin ulcers, can also be applied in wound bed preparation for severe limb trauma. Patients and MethodsThe three cases in this study required an average of 13 weeks of highly concentrated carbonated bathing, which led to significantly better wound bed preparation, even in the exposed bone and tendon regions. ResultsWe successfully achieved good functional limb reconstruction in patients with deep burns and severe open fractures by reducing wound infection and facilitating good wound bed preparation. ConclusionsHighly concentrated carbon dioxide bathing was sufficient to prevent frequent wound infections, even in severe extremity trauma involving large soft-tissue defects such as deep crush burns and Gustilo Anderson classification ≥3b open fractures of the extremities. To our knowledge, such interventions have not been reported in the past and are valuable as new procedures for wound bed preparation in severe extremity trauma from both cost and wound infection control perspectives.

Human Adipose-Derived Microvessel Fragments: A Natural Vascularization Units for Ischemic Diseases.

In plastic surgery tissue transplantation, tissue ischemia limits transplanted tissue survival. Adipose-derived stem cells (ASCs) and stromal vascular fraction (SVF) show potential for promoting angiogenesis and rescuing ischemic conditions. However, when SVF and ASC suspensions are utilized without the protection of extracellular matrix, the retention rate of transplanted cells tends to be diminished, leading to an unsatisfactory therapeutic outcome. To overcome this, adipose tissue-derived microvascular fragments (ad-MVFs) have emerged as a promising solution. We conducted enzymatic digestion on human adipose tissue to generate ad-MVFs. These fragments underwent a thorough characterization process, utilizing electron microscopy to assess their structural attributes and enabling a detailed analysis of their intricate morphology. Furthermore, our team investigated the cellular composition of these microvascular fragments, subsequently confirming their ability to enhance the viability of ischemic skin flaps. The resulting product primarily comprised fragments with sizes ranging from 20 to 50 µm, and some exhibited a sophisticated network-like structure. Electron microscopy examination revealed the presence of collagen components in the product. Additionally, flow cytometry analysis indicated a substantial abundance of adipose-derived stem cells and endothelial cells within these microvascular fragments. Significantly, when tested in treating an ischemic skin flap in a nude mouse model, the product exhibited superior therapeutic efficacy compared to SVF cell suspension. We have successfully generated human ad-MVFs and established standardized procedures. Compared with SVF, Ad-MVFs have a better effect in the treatment of ischemic diseases. 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 .

Topical Neuropeptide Y for Ischemic Skin Wounds.

Our objective was to investigate the effects of topically applied neuropeptide Y (NPY) on ischemic wounds. Initially, the animal model for ischemic wound healing was validated using 16 male Sprague Dawley albino rats. In the intervention study, an additional 28 rats were divided into three groups: NPY (0.025%), the positive control insulin-like growth factor-I (IGF-I, 0.0025%), and the hydrogel carrier alone (control). The hydrogel was selected due to its capacity to prolong NPY release (p < 0.001), as demonstrated in a Franz diffusion cell. In the animals, an 8 mm full-thickness wound was made in a pedunculated dorsal ischemic skin flap. Wounds were then treated and assessed for 14 days and collected at the end of the experiment for in situ hybridization analysis (RNAscope®) targeting NPY receptor Y2R and for meticulous histologic examination. Wound healing rates, specifically the percentage changes in wound area, did not show an increase with NPY (p = 0.907), but there was an increase with rhIGF-I (p = 0.039) compared to the control. Y2R mRNA was not detected in the wounds or adjacent skin but was identified in the rat brain (used as a positive control). Light microscopic examination revealed trends of increased angiogenesis and enhanced inflammatory cell infiltration with NPY compared to control. An interesting secondary discovery was the presence of melanophages in the wounds. Our findings suggest the potential of NPY to enhance neovascularization under ischemic wound healing conditions, but further optimization of the carrier and dosage is necessary. The mechanism remains elusive but likely involves NPY receptor subtypes other than Y2R.

Electrical stimulation promoting the angiogenesis in diabetic rat perforator flap through attenuating oxidative stress-mediated inflammation and apoptosis.

Skin flap transplantation is one of the effective methods to treat the diabetes-related foot ulceration, but the intrinsic damage to vessels in diabetes mellitus (DM) leads to the necrosis of skin flaps. Therefore, the discovery of a non-invasive and effective approach for promoting the survival of flaps is of the utmost importance. Electrical stimulation (ES) promotes angiogenesis and increases the proliferation, migration, and elongation of endothelial cells, thus being a potential effective method to improve flap survival. The purpose of this study was to elucidate the mechanism used by ES to effectively restore the impaired function of endothelial cells caused by diabetes. A total of 79 adult male Sprague-Dawley rats were used in this study. Gene and protein expression was assessed by PCR and western blotting, respectively. Immunohistochemistry and hematoxylin-eosin staining were performed to evaluate the morphology and density of the microvessels in the flap. The optimal duration for preconditioning the flap with ES was 7 days. The flap survival area percentage and microvessels density in the DMES group were markedly increased compared to the DM group. VEGF, MMP2, and MMP9 protein expression was significantly upregulated. ROS intensity was significantly decreased and GSH concentration was increased. The expression of IL-1β, MCP‑1, cleaved caspase-3, and Bax were downregulated in the DMES group, while TGF-β expression was upregulated. ES improves the angiogenesis in diabetic ischemic skin flaps by attenuating oxidative stress-mediated inflammation and apoptosis, eventually increasing their viability.

The effect of pitavastatin in an ischemic skin flap model in rats

The effect of pitavastatin in an ischemic skin flap model in rats

In Situ Monitoring and Assessment of Ischemic Skin Flap by High-Frequency Ultrasound and Quantitative Parameters.

Skin flap surgery is a critical procedure for treating severe skin injury in which post-surgery lesions must well monitored and cared for noninvasively. In the present study, attempts using high-frequency ultrasound imaging, quantitative parameters, and statistical analysis were made to extensively assess variations in the skin flap. Experiments were arranged by incising the dorsal skin of rats to create a skin flap using the chamber model. Measurements, including photographs, 30 MHz ultrasound B-mode images, skin thickness, echogenicity, Nakagami statistics, and histological analysis of post-surgery skin flap, were performed. Photograph results showed that color variations in different parts of the skin flap may readily correspond to ischemic states of local tissues. Compared to post-surgery skin flap on day 7, both integrated backscatter (IB) and Nakagami parameter (m) of the distal part of tissues were increased, and those of the skin thickness were decreased. Overall, relative skin thickness, IB, and m of the distal part of post-surgery skin flap varied from 100 to 67%, -66 to -61 dB, and 0.48 to 0.36, respectively. These results demonstrate that this modality and quantitative parameters can be feasibly applied for long-term and in situ assessment of skin flap tissues.

Evaluation of enteral and parenteral hyaluronic acid in induced ischemic skin flaps in rats: a double-blinded and randomized study.

To evaluate exogenous hyaluronic acid (HA) derived from bacterial fermentation through enteral and parenteral routes in ischemic skin flaps induced in rats, using clinical and histological exams; and interleukins (IL) as tissue inflammatory biomarkers. Sixty-four male adults Wistar rats with ischemic skin flaps on the dorsum were randomized into four groups, based on the treatment protocol: subcutaneous administration of saline solution (0.9%) (GI); oral administration of distilled water (GII); subcutaneous administration of HA (0.3%) (GIII); and oral administration of HA (1%) (GIV). Flaps of all groups were comparable regarding clinical and macroscopic evaluation, histological examination, pro-inflammatory cytokines (IL-1β, IL-6, and tumor necrosis factor-α) and anti-inflammatory cytokine IL-10. A lower percentage of necrosis was identified in flaps treated with subcutaneous administration of HA (0.3%). The pro- and anti-inflammatory cytokines, epidermis thickness, blood vessels, and inflammatory cells showed statistically significant inter-group and intra-group differences (p < 0.05). High molecular HA (1,400 ~ 2,000 kDa) administrated by subcutaneous or oral route exhibited beneficial effects in ischemic skin flaps of rats. However, subcutaneous administration of HA (0.3%) showed better results in terms of the percentage of necrosis and epithelialization.

Augmented Safety Profile of Ultrasound-Guided Gluteal Fat Transfer: Retrospective Study With 1815 Patients.

Gluteal augmentation with autologous fat transfer is one of the fastest growing aesthetic surgical procedures worldwide over the past decade. However, this procedure can be associated with high mortality from fatal pulmonary fat embolism events caused by intramuscular injection of fat. Ultrasound-guided fat grafting allows visualization of the transfer in the subcutaneous space, avoiding intramuscular injection. The aim of this study was to assess the safety and efficacy of gluteal fat grafting performed with ultrasound-guided cannulation. A retrospective chart review of all patients undergoing ultrasound-guided gluteal fat grafting at the authors' center between 2019 and 2022 was performed. All cases were performed by board-certified and board-eligible plastic surgeons under general anesthesia in ASA Class I or II patients. Fat was only transferred to the subcutaneous plane when over the gluteal muscle. Patients underwent postoperative follow-up from a minimum of 3 months up to 2 years. Results were analyzed with standard statistical tests. The study encompassed 1815 female patients with a median age of 34 years. Controlled medical comorbidities were present in 14%, with the most frequent being hypothyroidism (0.7%), polycystic ovarian syndrome (0.7%), anxiety (0.6%), and asthma (0.6%). Postoperative complications occurred in 4% of the total cohort, with the most common being seroma (1.2%), local skin ischemia (1.2%), and surgical site infection (0.8%). There were no macroscopic fat emboli complications or mortalities. These data suggest that direct visualization of anatomic plane injection through ultrasound guidance is associated with a low rate of complications. Ultrasound guidance is an efficacious adjunct to gluteal fat grafting and is associated with an improved safety profile that should be considered by every surgeon performing this procedure.

Regulation of Glucose Metabolism for Cell Energy Supply In Situ via High-Energy Intermediate Fructose Hydrogels.

The cellular functions, such as tissue-rebuilding ability, can be directly affected by the metabolism of cells. Moreover, the glucose metabolism is one of the most important processes of the metabolism. However, glucose cannot be efficiently converted into energy in cells under ischemia hypoxia conditions. In this study, a high-energy intermediate fructose hydrogel (HIFH) is developed by the dynamic coordination between sulfhydryl-functionalized bovine serum albumin (BSA-SH), the high-energy intermediate in glucose metabolism (fructose-1,6-bisphosphate, FBP), and copper ion (Cu2+). This hydrogel system is injectable, self-healing, and biocompatible, which can intracellularly convert energy with high efficacy by regulating the glucose metabolism in situ. Additionally, the HIFH can greatly boost cell antioxidant capacity and increase adenosine triphosphate (ATP) in the ischemia anoxic milieu by roughly 1.3 times, improving cell survival, proliferation and physiological functions in vitro. Furthermore, the ischemic skin tissue model is established in rats. The HIFH can speed up the healing of damaged tissue by promoting angiogenesis, lowering reactive oxygen species (ROS), and eventually expanding the healing area of the damaged tissue by roughly 1.4 times in vivo. Therefore, the HIFH can provide an impressive perspective on efficient in situ cell energy supply of damaged tissue.

Oxygen Saturation or Tissue Oxygen Determinations on Skin Whose Viability is at Risk.

The triad of ischaemia, neuropathy, and infection are among the principal causes of lower extremity wounds that are commonly prevalent in patients with diabetic foot (DF) a condition in which peripheral arterial disease commonly co-exists. The prevalence of this condition is increasing globally and with it, the mounting costs of its management. One aspect of management is saving limbs and or digits, a crucial part of this process is assessing tissue viability of skin which is a focus of this review: there are other aspects which are well described in the literature. Amputations are offered to limit the damage resulting from acute/chronic ischaemia. Holstein measured skin perfusion pressure using a radioisotope clearance technique to describe critically ischaemic skin; he found 30 mm Hg as the threshold above which healing may reliably be expected. Recent advances in vascular surgery and related technology have informed evidence-based advice to revascularize and save limbs; in practice, this may leave a wound in the distal skin unhealed; managing these raises questions of tissue viability. Much effort has been made to manage, prevent and to better understand these lower extremity wounds using measurements of tissue oxygen, oxygen saturation and skin imaging. The measurement techniques and their relevant merits are examined in this article. Advances in wound management systems and protocols can also facilitate the repair processes, and those which can have a particular impact on restoring or maintaining tissue perfusion are also discussed in the article.

Nesfatin-1 regulates the HMGB1-TLR4-NF-κB signaling pathway to inhibit inflammation and its effects on the random skin flap survival in rats

ObjectiveRandom skin flaps are often placed by plastic surgeons to treat limb deformities and dysfunction. Nesfatin-1 (NES) is a peptide that exerts angiogenic, anti-inflammatory, and anti-oxidant effects. We assessed the impact of NES on flap survival and the underlying mechanism. MethodsWe modified the McFarlane random skin flap rat model. Thirty-six male Sprague-Dawley rats were randomly divided into a control group (corn oil solution with DMSO), low-dose group (NES-L at 10 µg/kg/day), and high-dose group (NES-H at 20 µg/kg/day). On day 7 after surgery, average flap survival areas were calculated. Laser Doppler blood flow monitoring and lead oxide/gelatin angiography were used to evaluate blood perfusion and neovascularization, respectively. Flap histopathological status was evaluated by hematoxylin and eosin (H&E) staining. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) were determined. Immunohistochemical techniques were used to evaluate the expression of angiogenetic and inflammatory factors. ResultsIn the experimental groups, the mean skin flap survival areas and blood perfusion increased considerably. The SOD activities in the experimental groups increased and the MDA contents decreased. Immunohistochemically, VEGF expression was upregulated in the experimental groups and the expression levels of inflammatory factors decreased markedly. ConclusionNES inhibited ischemic skin flap necrosis, promoted angiogenesis, and reduced ischemia-reperfusion injury and inflammation. Inhibition of the inflammatory HMGB1-TLR4-NF-κB signal pathway, which reduced flap inflammation and oxidative stress, may explain the enhanced flap survival.