A Multifunctional, Tough, Stretchable, and Transparent Curcumin Hydrogel with Potent Antimicrobial, Antioxidative, Anti-inflammatory, and Angiogenesis Capabilities for Diabetic Wound Healing.

The treatment of diabetic chronic wounds is still faced with great challenges, mainly due to wound infection, excessive inflammation, and peripheral vascular disease in the wound area. Therefore, it is of great importance to develop a novel multifunctional hydrogel with high efficiency to accelerate diabetic wound healing. Curcumin (Cur), a Chinese herbal, has shown great potential in enhancing the healing of diabetic chronic wounds because of its immunomodulatory and pro-angiogenic properties. However, its low aqueous solubility, poor bioavailability, and chemical instability have limited its clinical applications. To address these current bottlenecks, novel poly(vinyl alcohol) (PVA)-chitosan (CS)/sodium alginate (SA)-Cur (PCSA) hydrogels were prepared for the first time, and they demonstrated all of the above intriguing performances by the Michael addition reaction of CS and Cur. PCSA hydrogels show multiple dynamic bonds, which possess strong mechanical properties (tensile stress: ∼0.980 MPa; toughness: ∼258.45 kJ/m3; and compressive strength: ∼7.38 MPa at strain of 80%). These intriguing performances provided an optimal microenvironment for cell migration and proliferation and also promoted the growth of blood vessels, leading to early angiogenesis. Importantly, the experimental results demonstrated that PCSA hydrogels can effectively transform pro-inflammatory M1 macrophages into anti-inflammatory M2 macrophages without the need for additional ingredients in vitro. Benefiting from these characteristics, a full-thickness diabetic wound in a rat model demonstrated that PCSA hydrogels can effectively accelerate wound healing via ROS-scavenging, downregulation of IL-1ß, and upregulation of CD31 expression, resulting in angiogenesis and collagen deposition. This strategy not only provides a simple and safe Cur-based hydrogel for diabetic wound healing but also highlights the significant potential for the development of high-performance biomaterials for promoting diabetic wound healing using traditional Chinese medicine.

Management of deep sacral and ischial pressure injuries with free-style local perforator flaps: A D+P+DPD model.

BACKGROUND: Previous reports on the treatment of sacral and ischial pressure injuries have not provided clear algorithms for surgical therapies. The objective of this study was to establish a reconstruction algorithm to guide the selection of an ideal free-style perforator flap that can be tailored to the defect in question. METHODS: We used 23 perforator flaps to reconstruct 14 sacral and 8 ischial defects in 22 patients over 5 years. A reconstruction algorithm system was developed based on the anatomical features of the perforator vessels (diameter, D; pulsatility [++∼+++], P) and their position in the skin island (DPD) (ie, D+P+DPD). A perforator-based propeller flap was applied as the first-line choice; if this plan was not feasible, we applied an altered V-Y advancement model or another second-choice technique. RESULTS: All flaps survived, and only 1 patient experienced partial wound dehiscence, which healed by secondary intention. After an average follow-up period of 11.2 months, no patient experienced recurrence or infection. CONCLUSIONS: Free-style perforator flap selection is determined by pressure injury and the desired advantage of a specific approach. The use of free-style perforator-based propeller flaps allows a surgeon to transfer healthy tissue into the defect, shifts the suture line away from the bony prominence, and preserves additional future donor sites. In cases where unexpected variations are encountered, the V-Y advancement model or another technique can be used. The simplified surgical algorithm (D+P+DPD) can provide versatility and reliability, achieve a durable, natural esthetic outcome, and minimize injuries to future donor sites.

Two gene clusters and their positive regulator SlMYB13 that have undergone domestication-associated negative selection control phenolamide accumulation and drought tolerance in tomato.

Among plant metabolites, phenolamides, which are conjugates of hydroxycinnamic acid derivatives and polyamines, play important roles in plant adaptation to abiotic and biotic stresses. However, the molecular mechanisms underlying phenolamide metabolism and regulation as well as the effects of domestication and breeding on phenolamide diversity in tomato remain largely unclear. In this study, we performed a metabolite-based genome-wide association study and identified two biosynthetic gene clusters (BGC7 and BGC11) containing 12 genes involved in phenolamide metabolism, including four biosynthesis genes (two 4CL genes, one C3H gene, and one CPA gene), seven decoration genes (five AT genes and two UGT genes), and one transport protein gene (DTX29). Using gene co-expression network analysis we further discovered that SlMYB13 positively regulates the expression of two gene clusters, thereby promoting phenolamide accumulation. Genetic and physiological analyses showed that BGC7, BGC11 and SlMYB13 enhance drought tolerance by enhancing scavenging of reactive oxygen species and increasing abscisic acid content in tomato. Natural variation analysis suggested that BGC7, BGC11 and SlMYB13 were negatively selected during tomato domestication and improvement, leading to reduced phenolamide content and drought tolerance of cultivated tomato. Collectively, our study discovers a key mechanism of phenolamide biosynthesis and regulation in tomato and reveals that crop domestication and improvement shapes metabolic diversity to affect plant environmental adaptation.

Integrated Transcriptomic and Metabolomic Analyses Reveal the Molecular and Metabolic Basis of Flavonoids in Areca catechu L.

Areca catechu L., of the Arecaceae family, is widely distributed in tropical Asia. In A. catechu, the extracts and compounds, including flavonoids, have various pharmacological activities. Although there are many studies of flavonoids, the molecular mechanism of their biosynthesis and regulation remains unclear in A. catechu. In this study, 331 metabolites were identified from the root, stem, and leaf of A. catechu using untargeted metabolomics, including 107 flavonoids, 71 lipids, 44 amino acids and derivatives, and 33 alkaloids. The transcriptome analysis identified 6119 differentially expressed genes, and some were enriched in the flavonoid pathway. To analyze the biosynthetic mechanism of the metabolic differences in A. catechu tissues, 36 genes were identified through combined transcriptomic and metabolomic analysis, in which glycosyltransferase genes Acat_15g017010 and Acat_16g013670 were annotated as being involved in the glycosylation of kaempferol and chrysin by their expression and in vitro activities. Flavonoid biosynthesis could be regulated by the transcription factors, AcMYB5 and AcMYB194. This study laid a foundation for further research on the flavonoid biosynthetic pathway of A. catechu.

Population analysis reveals the roles of DNA methylation in tomato domestication and metabolic diversity.

DNA methylation is an important epigenetic marker, yet its diversity and consequences in tomato breeding at the population level are largely unknown. We performed whole-genome bisulfite sequencing (WGBS), RNA sequencing, and metabolic profiling on a population comprising wild tomatoes, landraces, and cultivars. A total of 8,375 differentially methylated regions (DMRs) were identified, with methylation levels progressively decreasing from domestication to improvement. We found that over 20% of DMRs overlapped with selective sweeps. Moreover, more than 80% of DMRs in tomato were not significantly associated with single-nucleotide polymorphisms (SNPs), and DMRs had strong linkages with adjacent SNPs. We additionally profiled 339 metabolites from 364 diverse accessions and further performed a metabolic association study based on SNPs and DMRs. We detected 971 and 711 large-effect loci via SNP and DMR markers, respectively. Combined with multi-omics, we identified 13 candidate genes and updated the polyphenol biosynthetic pathway. Our results showed that DNA methylation variants could complement SNP profiling of metabolite diversity. Our study thus provides a DNA methylome map across diverse accessions and suggests that DNA methylation variation can be the genetic basis of metabolic diversity in plants.

A modified perforator-based stepladder V-Y advancement flap in the Achilles tendon area for coverage of larger posterior heel defects.

BACKGROUND: Posterior heel defect coverage is challenging because of the paucity of suitable flaps. The traditional local stepladder V-Y advancement flap is recommended only for small defects because of the lack of an axial pedicle. This study reports our experience of using the perforator-based stepladder V-Y advancement flaps in a larger posterior heel defect repair. METHODS: Twenty-two patients with posterior heel defects were treated with modified perforator-based stepladder V-Y advancement flaps in the Achilles tendon area for 11 years. Sixteen males and six females aged 3-74 years underwent surgery. The defect size, perforator characteristics, flap size, flap movement, sural nerve, lesser saphenous vein, deep fascia, flap survival, and outcome quality were analyzed. RESULTS: The perforators were found to predominate within two 2-cm intervals: 0-2 cm and 4-6 cm proximal to the tip of the lateral malleolus. Twenty-one perforator-based flaps healed uneventfully, and only one developed tip necrosis on the lower edge, which healed by secondary intention. The maximum distance of distal movement was 5.0 cm for the modified flap in contrast to 2.5 cm for the traditional flap. All flaps allowed adequate and durable reconstruction to be achieved, with excellent contouring after 2-28 months of follow-up. CONCLUSIONS: The perforator-based stepladder V-Y advancement flap resulted in good outcomes for larger posterior heel defects compared with conventional transfer methods. The flap is a reliable, well-vascularized, sensate, and pliable local flap option that uses similar tissue from adjacent skin for defect repair and creates an internal gliding surface for the Achilles tendon.

A new skin flap from the zygomaticotemporal region: Anatomical study and clinical application to eyelid reconstruction.

BACKGROUND: Eyelid reconstruction is a demanding task faced by plastic surgeons. Island flaps from the zygomaticotemporal region, where the zygomatico-orbital artery predominates in vascularization, represent the recent local approaches to this problem. Questions exist as to where and on what element the flap should be based, and whether or not they should be adapted in relation to the behavior of the zygomatico-orbital artery. METHODS AND MATERIALS: A total of 22 fresh-frozen adult cadaver heads were employed. The fasciocutaneous perforators of the zygomatico-orbital artery and their anastomoses with the surrounding arteries, especially those in the upper palpebra, were investigated. On this basis, a distally based perforator flap was created and executed for eyelid reconstruction in 7 patients. RESULT: The zygomatico-orbital artery was interconnected through its perforators with the subdermal plexus over the zygomaticotemporal region and with the arteries in the surroundings. The transverse facial artery took the place of zygomatico-orbital artery where it was absent. Both the arteries anastomosed consistently with the superficial orbital arcade at a predictable site. All 7 flaps survived completely. CONCLUSION: A new distally based perforator flap from the zygomaticotemporal region is described regarding its anatomical basis and clinical applications to eyelid reconstruction. With a vascular axis consistently present and a pivot adjacent to the defects, the flap is more reliable in vascularization, and less harm to its donor site than orbicularis oculi myocutaneous flaps, and poses no concern about whether the zygomatico-orbital artery is present or not.

Erratum: "Baicalin prevents pulmonary arterial remodeling in vivo via the AKT/ERK/NF-κB signaling pathways".

[This corrects the article DOI: 10.1177/2045894019878599.].

Flap failure prediction in microvascular tissue reconstruction using machine learning algorithms.

BACKGROUND: Microvascular tissue reconstruction is a well-established, commonly used technique for a wide variety of the tissue defects. However, flap failure is associated with an additional hospital stay, medical cost burden, and mental stress. Therefore, understanding of the risk factors associated with this event is of utmost importance. AIM: To develop machine learning-based predictive models for flap failure to identify the potential factors and screen out high-risk patients. METHODS: Using the data set of 946 consecutive patients, who underwent microvascular tissue reconstruction of free flap reconstruction for head and neck, breast, back, and extremity, we established three machine learning models including random forest classifier, support vector machine, and gradient boosting. Model performances were evaluated by the indicators such as area under the curve of receiver operating characteristic curve, accuracy, precision, recall, and F1 score. A multivariable regression analysis was performed for the most critical variables in the random forest model. RESULTS: Post-surgery, the flap failure event occurred in 34 patients (3.6%). The machine learning models based on various preoperative and intraoperative variables were successfully developed. Among them, the random forest classifier reached the best performance in receiver operating characteristic curve, with an area under the curve score of 0.770 in the test set. The top 10 variables in the random forest were age, body mass index, ischemia time, smoking, diabetes, experience, prior chemotherapy, hypertension, insulin, and obesity. Interestingly, only age, body mass index, and ischemic time were statistically associated with the outcomes. CONCLUSION: Machine learning-based algorithms, especially the random forest classifier, were very important in categorizing patients at high risk of flap failure. The occurrence of flap failure was a multifactor-driven event and was identified with numerous factors that warrant further investigation. Importantly, the successful application of machine learning models may help the clinician in decision-making, understanding the underlying pathologic mechanisms of the disease, and improving the long-term outcome of patients.

The effect of inhibiting exosomes derived from adipose-derived stem cells via the TGF-ß1/Smad pathway on the fibrosis of keloid fibroblasts.

BACKGROUND: The main mechanism of keloid formation is that keloid fibroblasts (KFs) apoptosis is inhibited, leading to excessive proliferation. Transforming growth factor-ß1 (TGF-ß1) is a key signal molecule in the process of regulating cell fibrosis. This paper discusses the effect of adipose-derived stem cell exosomes (ADSCs-EXO) on the proliferation and apoptosis of KFS and its possible mechanism, in order to provide reference for the clinical intervention of hypertrophic scar. METHODS: ADSCs were isolated and cultured from human adipose tissue, the supernatant was collected, and the exosomes secreted by ADSCs-EXO were extracted by ultracentrifugation. At the same time, KFs were cultured from human keloid tissue to P3 generation, and then divided into four groups: control group, experimental group A, experimental group B and experimental group C. KFs were then cultured with four concentrations of ADSCs-EXO (0, 1, 10, and 100 µg/mL, respectively). After 24 hours, cells in each group were taken to detect the following: proliferation of cells in each group using the cell counting Kit 8 (CCK-8) method, cell migration ability via the Transwell test, cell apoptosis by flow cytometry, collagen synthesis using the hydroxyproline method, messenger ribonucleic acid (mRNA) expression of fibrosis-related genes in each group by real-time fluorescent polymerase chain amplification, and the expression of fibrosis-related proteins in the cells of each group by western blotting. RESULTS: Compared with the control group, the proliferation rate, migration rate, and collagen synthesis levels in the three experimental groups decreased with the increase of ADSCs-EXO concentration, while the apoptosis rate in the three experimental groups increased with the increase of ADSCs-EXO concentration, and the differences were statistically significant (P<0.05). Also, compared with the control group, the relative mRNA and protein expression of alpha-smooth muscle actin (α-SMA), TGF-ß1, and Smad3 in the three groups decreased significantly, while the expression of three kinds of mRNA and protein decreased with the increase of ADSCs-EXO concentration, and the differences were statistically significant (P<0.05). CONCLUSIONS: ADSCs-EXO may inhibit the proliferation and migration, and promote the apoptosis of KFs by inhibiting the expression of the TGF-ß1/Smad pathway.

Baicalin prevents pulmonary arterial remodeling in vivo via the AKT/ERK/NF-κB signaling pathways.

Pulmonary arterial hypertension is a rapidly progressive and often fatal disease. As the pathogenesis of pulmonary arterial hypertension remains unclear, there is currently no good drug for pulmonary arterial hypertension and new therapy is desperately needed. This study investigated the effects and mechanism of baicalin on vascular remodeling in rats with pulmonary arterial hypertension. A rat pulmonary arterial hypertension model was constructed using intraperitoneal injection of monocrotaline, and different doses of baicalin were used to treat these rats. The mean pulmonary arterial pressure (mPAP) and right ventricular systolic pressure (RVSP) were measured with a right heart catheter. Moreover, the hearts were dissected to determine the right ventricular hypertrophy index (RVHI). The lung tissues were stained with H&E and Masson's staining to estimate the pulmonary vascular remodeling and collagen fibrosis, and the expression of proteins in the AKT, ERK, and NF-κB p65 phosphorylation (p-AKT, p-ERK, p-p65) was examined by Western blot analysis. We found that compared with untreated pulmonary arterial hypertension rats, baicalin ameliorated pulmonary vascular remodeling and cardiorespiratory injury, inhibited p-p65 and p-ERK expression, and promoted p-AKT and p-eNOS expression. In conclusion, baicalin interfered with pulmonary vascular remodeling and pulmonary arterial hypertension development in rats through the AKT/eNOS, ERK and NF-κB signaling pathways.

Tissue Inhibitor of Matrix Metalloproteinases-1 Knockdown Suppresses the Proliferation of Human Adipose-Derived Stem Cells.

Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a multifunctional matrix metalloproteinase, and it is involved in the regulation of cell proliferation and apoptosis in various cell types. However, little is known about the effect of TIMP-1 expression on the proliferation of adipose-derived stem cells (ADSCs). Therefore, TIMP-1 expression in the ADSCs was firstly detected by western blotting, and TIMP-1 gene was knocked down by lentivirus-mediated shRNA. Cell proliferation was then evaluated by MTT assay and Ki67 staining, respectively. Cell cycle progression was determined by flow cytometry. The changes of p51, p21, cyclin E, cyclin-dependent kinase 2 (CDK2), and P-CDK2 caused by TIMP-1 knockdown were detected by western blotting. The results indicated that ADSCs highly expressed TIMP-1 protein, and the knockdown of TIMP-1 inhibited cell proliferation and arrested cell cycle progression at G1 phase in the ADSCs possibly through the upregulation of p53, p21, and P-CDK2 protein levels and concurrent downregulation of cyclin E and CDK2 protein levels. These findings suggest that TIMP-1 works as a positive regulator of cell proliferation in ADSCs.

Xenotransplantation of human adipose-derived stem cells in zebrafish embryos.

Zebrafish is a widely used animal model with well-characterized background in developmental biology. The fate of human adipose-derived stem cells (ADSCs) after their xenotransplantation into the developing embryos of zebrafish is unknown. Therefore, human ADSCs were firstly isolated, and then transduced with lentiviral vector system carrying a green fluorescent protein (GFP) reporter gene, and followed by detection of their cell viability and the expression of cell surface antigens. These GFP-expressing human ADSCs were transplanted into the zebrafish embryos at 3.3-4.3 hour post-fertilization (hpf). Green fluorescent signal, the proliferation and differentiation of human ADSCs in recipient embryos were respectively examined using fluorescent microscopy and immunohistochemical staining. The results indicated that human ADSCs did not change their cell viability and the expression levels of cell surface antigens after GFP transduction. Microscopic examination demonstrated that green fluorescent signals of GFP expressed in the transplanted cells were observed in the embryos and larva fish at post-transplantation. The positive staining of Ki-67 revealed the survival and proliferation of human ADSCs in fish larvae after transplantation. The expression of CD105 was observable in the xenotransplanted ADSCs, but CD31 expression was undetectable. Therefore, our results indicate that human ADSCs xenotransplanted in the zebrafish embryos not only can survive and proliferate at across-species circumstance, but also seem to maintain their undifferentiation status in a short term. This xenograft model of zebrafish embryos may provide a promising and useful technical platform for the investigation of biology and physiology of stem cells in vivo.

Lateral calcaneal artery perforator-based skin flaps for coverage of lower-posterior heel defects.

BACKGROUND: Perforator-based flaps have been explored across almost all of the lower leg except in the Achilles tendon area. This paper introduced a perforator flap sourced from this area with regard to its anatomic basis and clinical applications. METHODS: Twenty-four adult cadaver legs were dissected to investigate the perforators emerging along the lateral edge of the Achilles tendon in terms of number and location relative to the tip of the lateral malleolus, and distribution. Based on the anatomic findings, perforator flaps, based on the perforator(s) of the lateral calcaneal artery (LCA) alone or in concert with the perforator of the peroneal artery (PA), were used for reconstruction of lower-posterior heel defects in eight cases. Postoperatively, subjective assessment and Semmes-Weinstein filament test were performed to evaluate the sensibility of the sural nerve-innerved area. RESULTS: The PA ended into the anterior perforating branch and LCA at the level of 6.0 ± 1.4 cm (range 3.3-9.4 cm) above the tip of the lateral malleolus. Both PA and LCA, especially the LCA, gave rise to perforators to contribute to the integument overlying the Achilles tendon. Of eight flaps, six were based on perforator(s) of the LCA and two were on perforators of the PA and LCA. Follow-up lasted for 6-28 months (mean 13.8 months), during which total flap loss and nerve injury were not found. Functional and esthetic outcomes were good in all patients. CONCLUSION: The integument overlying the Achilles tendon gets its blood supply through the perforators of the LCA primarily and that of through the PA secondarily. The LCA perforator(s)-based and the LCA plus PA perforators-based stepladder flap is a reliable, sensate flap, and should be thought of as a valuable procedure of choice for coverage of lower-posterior heel defects in selected patients.