Highly efficient semiconductor modules making controllable parallel microchannels for non-compressible hemorrhages.

Nature makes the most beautiful solution to involuted problems. Among them, the parallel tubular structures are capable of transporting fluid quickly in plant trunks and leaf stems, which demonstrate an ingenious evolutionary design. This study develops a mini-thermoelectric semiconductor P-N module to create gradient and parallel channeled hydrogels. The modules decrease quickly the temperature of polymer solution from 20 °C to -20 °C within 5 min. In addition to the exceptional liquid absorption rate, the foams exhibited shape memory mechanics. Our mini device universally makes the inspired structure in such as chitosan, gelatin, alginate and polyvinyl alcohol. Non-compressible hemorrhages are the primary cause of death in emergency. The rapid liquid absorption leads to fast activation of coagulation, which provides an efficient strategy for hemostasis management. We demonstrated this by using our semiconductor modules on collagen-kaolin parallel channel foams with their high porosity (96.43%) and rapid expansion rate (2934%). They absorb liquid with 37.25 times of the own weight, show 46.5-fold liquid absorption speed and 24-fold of blood compared with random porous foams. These superior properties lead to strong hemostatic performance in vitro and in vivo.

Extracellular Matrices as Bioactive Materials for In Situ Tissue Regeneration.

Bioactive materials based on a nature-derived extracellular matrix (NECM) represent a category of biomedical devices with versatile therapeutic applications in the realms of tissue repair and engineering. With advancements in decellularization technique, the inherent bioactive molecules and the innate nano-structural and mechanical properties are preserved in three-dimensional scaffolds mainly composed of collagens. Techniques such as electrospinning, three-dimensional printing, and the intricate fabrication of hydrogels are developed to mimic the physical structures, biosignalling and mechanical cues of ECM. Until now, there has been no approach that can fully account for the multifaceted properties and diverse applications of NECM. In this review, we introduce the main proteins composing NECMs and explicate the importance of them when used as therapeutic devices in tissue repair. Nano-structural features of NECM and their applications regarding tissue repair are summarized. The origins, degradability, and mechanical property of and immune responses to NECM are also introduced. Furthermore, we review their applications, and clinical features thereof, in the repair of acute and chronic wounds, abdominal hernia, breast deformity, etc. Some typical marketed devices based on NECM, their indications, and clinical relevance are summarized.

Silk Nanofiber Scaffolds with Multiple Angiogenic Cues to Accelerate Wound Regeneration.

Niches with multiple physical and chemical cues can influence the fate of cells and tissues in vivo. Simulating the in vivo niche in the design of bioactive materials is a challenge, particularly to tune multiple cues simultaneously in the same system. Here, an assembly strategy was developed to regulate multiple cues in the same scaffold based on the use of two silk nanofiber components that respond differently during the fabrication processes. An aqueous solution containing the two components, amorphous silk nanofibers (ASNFs) and ß-sheet-rich silk nanofibers (BSNFs), was sequentially treated with an electrical field and freeze-drying processes where the BSNFs oriented to the electrical field, while the ASNFs formed stable porous structures during the lyophilization process to impact the mechanical properties. Bioactive cargo, such as deferoxamine (DFO), was loaded on the BSNFs to enrich cell responses with the scaffolds. The in vitro results revealed that the loaded DFO and the anisotropic structures with improved mechanical properties resulted in better vascularization than those of the scaffolds without the anisotropic features. The multiple cues in the scaffolds provided angiogenic niches to accelerate wound healing.

Development of Organs-on-Chips and Their Impact on Precision Medicine and Advanced System Simulation.

Drugs may undergo costly preclinical studies but still fail to demonstrate their efficacy in clinical trials, which makes it challenging to discover new drugs. Both in vitro and in vivo models are essential for disease research and therapeutic development. However, these models cannot simulate the physiological and pathological environment in the human body, resulting in limited drug detection and inaccurate disease modelling, failing to provide valid guidance for clinical application. Organs-on-chips (OCs) are devices that serve as a micro-physiological system or a tissue-on-a-chip; they provide accurate insights into certain functions and the pathophysiology of organs to precisely predict the safety and efficiency of drugs in the body. OCs are faster, more economical, and more precise. Thus, they are projected to become a crucial addition to, and a long-term replacement for, traditional preclinical cell cultures, animal studies, and even human clinical trials. This paper first outlines the nature of OCs and their significance, and then details their manufacturing-related materials and methodology. It also discusses applications of OCs in drug screening and disease modelling and treatment, and presents the future perspective of OCs.

Eschar dissolution and the immunoregulator effect of keratinase on burn wounds.

At present, enzyme debridement preparation has shown a good curative effect on eschar removal of burn wounds. Keratinase has shown great potential in enzymatic debridement because of its good fibrin-degrading ability. In this study, the debridement of keratinase was examined by using a third degree burn wound model in rats. We observed the wound, and keratinase shortened the time of eschar dissolution after debridement. Histopathology and immunofluorescence staining showed that the eschar in the keratinase group became thinner, inflammatory cell infiltration in the wound increased, the fluorescence intensity of the macrophage surface marker CD68 increased, and the CD163/CD86 ratio increased. In bone marrow-derived macrophages (BMDMs), there was no significant difference in the activity of CCK-8 in cells in the keratinase group compared with the control group. The fluorescence intensity of the keratinase group was higher than that of the control group. At 12 h, the cell scratches were obviously closed. The number of migrated Transwell cells increased. Flow cytometry and immunofluorescence analysis showed increased expression of CD206 and Arg-1 and decreased expression of CD86 and iNOS. The gene expression of the Arg-1, iNOS and IL-10 was increased, as shown by qPCR. The secretion of IL-10 was increased and TNF-α was decreased, as shown by ELISA. We concluded that keratinase dissolution of eschar not only has a hydrolytic effect on eschar but may also affect immune regulation to enhance the migration and phagocytosis of macrophages, promote the polarization of macrophages, and further enhance the effect of eschar dissolution. Therefore, keratinase may have good prospects for the debridement of burn wounds.

Hydrophobic aerogel-modified hemostatic gauze with thermal management performance.

Current hemostatic agents or dressings are not efficient under extremely hot and cold environments due to deterioration of active ingredients, water evaporation and ice crystal growth. To address these challenges, we engineered a biocompatible hemostatic system with thermoregulatory properties for harsh conditions by combining the asymmetric wetting nano-silica aerogel coated-gauze (AWNSA@G) with a layer-by-layer (LBL) structure. Our AWNSA@G was a dressing with a tunable wettability prepared by spraying the hydrophobic nano-silica aerogel onto the gauze from different distances. The hemostatic time and blood loss of the AWNSA@G were 5.1 and 6.9 times lower than normal gauze in rat's injured femoral artery model. Moreover, the modified gauze was torn off after hemostasis without rebleeding, approximately 23.8 times of peak peeling force lower than normal gauze. For the LBL structure, consisting of the nano-silica aerogel layer and a n-octadecane phase change material layer, in both hot (70 °C) and cold (-27 °C) environments, exhibited dual-functional thermal management and maintained a stable internal temperature. We further verified our composite presented superior blood coagulation effect in extreme environments due to the LBL structure, the pro-coagulant properties of nano-silica aerogel and unidirectional fluid pumping of AWNSA@G. Our work, therefore, shows great hemostasis potential under normal and extreme temperature environments.

Fabrication of biologically inspired electrospun collagen/silk fibroin/bioactive glass composited nanofibrous to accelerate the treatment efficiency of wound repair.

A triple-layer matrix Collagen/Silk fibroin/Bioactive glass composited Nanofibrous was fabricated by linking electrospinning and freeze-drying systems, this typical three layered composite with a nanofibrous fragment as the key (top) layer, middle portion as inferior, and a spongy porous fragment as the third (bottom) deposit to develop the synergistic effect of composite materials resultant to physical and biological performances. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy were used to assess the final material's physicochemical properties (SEM). The triple-layer matrix had a nanofibrous and porous structure, which has qualities including high porosity, swelling, and stability, which are important in soft-tissue engineering. NIH 3 T3 fibroblast and humanoid keratinocyte (HaCaT) cell lines were also used to investigate the matrix's in vitro biological and fluorescent capabilities, which showed excellent cell adherence and proliferation across the composite layers. The synergistic arrangement of nanofibrous substantial deposition onto collagenous with silk fibroin candidates has therefore proven effective in the construction of a tri-layer matrix for skin-tissue-engineering applications.

Application of Comfort Therapy under eCASH Concept in Acute and Chronic Wound Treatment.

INTRODUCTION: Given the new ideas on wound care offered by the eCASH (early Comfort using Analgesia, minimal Sedatives, and maximal Humane care) and the substantial differences in clinical treatment between acute and chronic wounds, we aimed to investigate the effect of comfort therapy under the eCASH concept on analgesic sedation and accelerated wound healing in patients with acute or chronic wounds. METHODS: This randomized clinical study was conducted in two parts: acute wounds and chronic wounds. Patients with acute wounds were allocated into the acute wound control group (AWCG) and the acute wound experimental group (AWEG). Patients with chronic wounds were allocated into the chronic wound control group (CWCG) and two experimental groups, in which they received intermittent negative pressure therapy (IPTEG) and continuous negative pressure therapy (CPTEG). On the basis of the standard treatment for patients in the control group, eCASH therapy was used in the experimental groups. In addition, pain intensity and procedural anxiety were evaluated using the visual analogue score (VAS) and the Hamilton Anxiety Scale (HAM-A). In addition, clinical effects were assessed on the basis of the size of the surface area, rate of healing, and concentration of pro-inflammatory factors (IL-1, IL-6, TNF-α) and growth factors (VEGF, bFGF, TGF-ß1). RESULTS: Compared with the control group, the VAS score and HAM-A score in the experimental groups were significantly decreased after intervention (P < 0.05). After intervention, the levels of IL-1ß, IL-6, and TNF-α in AWEG, IPTEG, and CPTEG were significantly lower than those in AWCG. In addition, the levels of VEGF, bFGF, and TGF-ß1 in IPTEG and CPTEG were significantly higher than those in CWCG (P < 0.05). CONCLUSION: These results indicated that comfort therapy under the eCASH concept has a significant effect on ameliorating the pain and anxiety of patients, reducing the inflammatory reaction during the period of wound healing in the treatment of acute and chronic wounds. CLINICAL TRIAL REGISTRY: The trial has been registered in the Chinese Clinical Trial Registry (ChiCTR2200057981).

The Nocardia Rubra Cell Wall Skeleton Regulates Macrophages and Promotes Wound Healing.

The Nocardia rubra cell wall skeleton (Nr-CWS) is an immunomodulator used clinically for its ability to modulate the body's immune function. Macrophages are an important hub of the immune response during wound healing. In this study, we hypothesized that a Nr-CWS could modulate macrophage physiological activities, polarize macrophages toward M2, and promote wound healing. Through in vivo experiments, we made two full-thickness excisional wounds on the backs of mice; one was treated with a Nr-CWS, and the other was treated with saline. We photographed and recorded the wound change every other day. We observed the histopathological examination and collagen deposition using H&E and Masson staining, then analyzed the macrophage surface markers using immunofluorescence. Through in vitro experiments, we studied the effect of the Nr-CWS on RAW264.7 cells through CCK8, transwell, flow cytometry, western blot, immunofluorescence, and ELISA. We found that the Nr-CWS can enhance the proliferation, migration, and phagocytosis of macrophages. In addition, it can promote the recruitment of macrophages on the wound surface, polarize macrophages to M2, and increase the expression of pro-healing cytokines. Ultimately, the Nr-CWS accelerated wound healing.

Corrigendum: Focusing on Mechanoregulation Axis in Fibrosis: Sensing, Transduction and Effecting.

[This corrects the article DOI: 10.3389/fmolb.2022.804680.].

Focusing on Mechanoregulation Axis in Fibrosis: Sensing, Transduction and Effecting.

Fibrosis, a pathologic process featured by the excessive deposition of connective tissue components, can affect virtually every organ and has no satisfactory therapy yet. Fibrotic diseases are often associated with organ dysfunction which leads to high morbidity and mortality. Biomechanical stmuli and the corresponding cellular response havebeen identified in fibrogenesis, as the fibrotic remodeling could be seen as the incapacity to reestablish mechanical homeostasis: along with extracellular matrix accumulating, the physical property became more "stiff" and could in turn induce fibrosis. In this review, we provide a comprehensive overview of mechanoregulation in fibrosis, from initialing cellular mechanosensing to intracellular mechanotransduction and processing, and ends up in mechanoeffecting. Our contents are not limited to the cellular mechanism, but further expand to the disorders involved and current clinical trials, providing an insight into the disease and hopefully inspiring new approaches for the treatment of tissue fibrosis.

Fabrication of homogeneously-aligned nano-fillers encapsulated silk fibroin electrospun nanofibers for improved fibroblast attachment, epithelialization, and collagen depositions: in vitro and in vivo wound healing evaluation.

Curcumin (CUR), a natural compound found in turmeric that has multiple biological functions such as antibacterial, anti-oxidant, anti-cancer, and wound healing properties due to its hydrophobicity CUR solubilization is a great challenge. In this study, the electrospinning process is used to fabricate a novel active wound dressing based on CUR loaded silk fibroin (SF)/hydroxyapatite (HAp) (SF/HAp-CUR) nanofibers in diabetic rats. The incorporation of CUR into the SF/HAp-CUR nanofibers had an obvious effect on the morphology and dimension of SF/HAp-CUR nanofibers characterized by SEM analysis. Morphological analysis revealed that the average fiber diameter of the SF/HAp, SF/HAp-CUR(1.0%), SF/HAp-CUR(3.0%), and SF/HAp-CUR(5.0%) nanofibers were calculated to be 461 ± 65 nm, 323 ± 90 nm, 412 ± 110, and 497 ± 118 nm. In addition of CUR in the SF/HAp nanofibers significantly improved the mechanical properties in terms of enhanced elongation at break and tensile strengths. The percentages of water uptake and porosity of SF/HAp-CUR nanofibers were 143.7 ± 4.05% and 92.5 ± 3.40%, respectively. The results showed that CUR presented a sustained release behavior from SF/HAp-CUR nanofibers and maintained its free radical scavenging ability. The prepared nanofibers surface interaction was confirmed by FT-IR and XRD analysis. Antibacterial tests revealed SF/HAp-CUR on day 14 improved the bacterial embarrassment of both E. coli and S. aureus by 4 to 5-fold, respectively. The cell cytotoxicity with L929 mouse fibroblasts on the SF/HAp-CUR nanofibers was very low at 7.7 ± 1.75% on day 14. In vivo wound healing showed that the treatment using SF/HAp-CUR nanofibers significantly increased the rate of wound closure (99.6 ± 0.86%) on day 21 compared with that using SF/HAp nanofibers (67.7 ± 4.25%). These results showed that the delivery of SF/HAp-CUR nanofibers can facilitate antibacterial, anti-oxidant, cytotoxicity of wound healing properties.

Effect of the Mini-Nutritional Assessment-Short Form in Elderly Burn Patients.

Nutritional assessment can early identify patients who are malnourished and at risk of malnutrition. To examine the effect of nutritional status on wound healing in elderly burn patients, we used the Mini-Nutritional Assessment-Short Form (MNA-SF) to measure the nutritional status of elderly patients. This study aimed to examine the role of MNA-SF in elderly burn patients through the correlation analysis of wound healing indicators and MNA-SF score. This was a prospective observational and cross-sectional study. This study used the MNA-SF to investigate the elderly burn patients at the department of burn. According to the score, the patients fell into three groups: good nutritional status (more than 12 points), malnutrition risk (8-11 points), and malnutrition (0-7 points). At the same time, we measured and compared the wound healing indicators among the three groups of patients, and detected the correlation. The results showed gender had a slight influence on the score of nutritional status, while age was negatively correlated with the MNA-SF score and nutrition-related indicators. There was a low positive linear correlation between the wound healing percent area change or wound healing rate of patients and the score of the MNA-SF. This study finds malnutrition is common among hospitalized elderly burn patients. The application of the MNA-SF in elderly burn patients is efficient and accurate to identify malnutrition early and prevent further obstruction of the normal wound healing, which can provide reference points for early nutrition intervention programs.

First Report of Botryosphaeria dothidea Causing Leaf Spot on Kadsura coccinea in China.

Kadsura coccinea (Lem.) A. C. Smith, belonging to Schisandraceae, is an evergreen, woody climbing plant that is distributed widely in southwest China. Additionally, K.coccinea is used as an ethnic medicine and its main chemical components are lignin and terpenoids. The roots of the plant have been effectively used for treatment of cancer and dermatosis and as an anodyne to relieve pain (Song et al. 2010). In June 2019, a leaf spot disease on K. coccinea was first observed in a greenhouse in Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou Province, China. Over 300 plants were surveyed in the three greenhouses, and nearly 70% of the plants were infected. The diseased plants grew poorly and appeared stunted, and severely affected plants died. The symptoms occurred on leaves as small brown spots initially and then developed into suborbicular or irregular-shaped brown necrotic lesions, which often displayed irregular concentric rings. Four diseased leaves from four symptomatic Kadsura coccinea plants were randomly collected for pathogen isolation. Diseased tissues were cut into about 2mm diameter fragments, surface sterilized with 75% ethanol for 15 s and 1% NaClO for 2 min, and then rinsed twice in sterilized distilled water. After being dried on sterilized filter paper, the fragments were placed on potato dextrose agar (PDA) and incubated at 25°C in the dark for 5 days. The same fungus was isolated in 95% of the samples. A representative isolate, F2020003 was used for morphological and molecular characterization. The colonies were initially white, gradually turning gray-green to dark gray after 7 days, with abundant gray aerial mycelium. Conidia were one-celled, hyaline, fusoid to ellipsoid and measured 24.3 ± 1.9 × 4.8 ± 0.7 µm (n = 50). The conidial morphology matched the description of Botryosphaeria dothidea (Slippers et al. 2004). To verify identity, the partial sequences of the internal transcribed spacer region, translation elongation factor 1 alpha genes and beta-tubulin, were amplified from isolate F2020003 with primers ITS1/ITS4 (GenBank accession no. MW111267), EF1-728F/EF1-986R (GenBank accession no. MW196739) and BT-2a/BT-2b (GenBank accession no. MW206378), respectively（Sun et al. 2014）. The isolates were confirmed as B. dothidea based on morphological comparisons and BLAST searches (Zhai et al. 2014). To assess pathogenicity, five healthy leaves on each of the three 6-month-old healthy K. coccinea plants were wound inoculated with a sterilized needle. Mycelium plugs (4 mm in diameter) taken from a 5-day-old culture on PDA were inoculated on surface-sterilized leaves (sprayed with 75% ethanol). PDA plugs with no mycelium were used as a control. Plants with treated leaves were covered with plastic bags and incubated in a greenhouse at 25°C. The pathogenicity test was repeated three times. Within 4 days, all the inoculated points showed lesions similar to those previously observed in the greenhouse, whereas controls were asymptomatic. Fungi re-isolated from inoculated leaves were confirmed as B. dothidea on the basis of morphological and molecular characterization as described above. B. dothidea is a member of Botryosphaeriaceae, it has been reported to cause leaf spot on Celtis sinensis (Wang et al., 2020) and branch canker on Malosma laurina (Aguirre et al., 2018) in China. To our knowledge, this is the first report of B. dothidea causing leaf spot on K. coccinea in China. The identification of this pathogen will be helpful to prevent and control this disease in the future.

Metabolomic study of the soybean pastes fermented by the single species Penicillium glabrum GQ1-3 and Aspergillus oryzae HGPA20.

Penicillium glabrum GQ1-3 and Aspergillus oryzae HGPA20 isolated from home-made soybean pastes were separately inoculated into soybean paste subjected to brine fermentation for 90 days. The amino acid nitrogen contents of the two fermentation systems were detected every 10 days, and both reached the maximum level at 40 days. The samples fermented for 40 days were analyzed via gas chromatography-time of flight mass spectrometry. Using univariate, multivariate and KEGG analyses, 72 differential metabolites were obtained, and 7 metabolic pathways closely related to fermentation were screened. The relative contents of 2-oxoglutarate, ornithine, glutamine, and citrulline were higher in GQ1-3, whereas those of l-homoserine, aspartic acid, and asparagine were higher in HGPA20. These findings indicate that α-ketoglutaric acid-derived amino acid synthesis is preponderant in GQ1-3, whereas oxaloacetate-derived type is predominant in HGPA20. The different pathways of amino acid synthesis lead to the distinct nutrients and umami substances in the fermented soybean pastes.

[National experts consensus on clinical application of collagen-based wound biomaterials (2018 version)].

Collagen, as the main structural protein in human body, plays an important role in the wound healing process. Due to their inherent hemostatic characteristics, good biocompatibility, low immunogenicity, as well as controllable biodegradability, collagen-based materials have attracted much attention. In this article, we mainly introduce the characteristics of collagen-based wound biomaterials and the application mechanism as scaffold and wound dressing. And the standard and unified experts' consensus formed on the clinical indications, recommended applications, contraindications, and matters needing attention. The consensus wound help clinicians and patients to recognize collagen-based wound biomaterials correctly and use them rationally.