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Extrusion-based bioprinting (EBB) holds potential for regenerative medicine. However, the widely-used bioinks of EBB exhibit some limitations for skin regeneration, such as unsatisfactory bio-physical (i.e., mechanical, structural, biodegradable) properties and compromised cellular compatibilities, and the EBB-based bioinks with therapeutic effects targeting cutaneous wounds still remain largely undiscussed. In this review, the printability considerations for skin bioprinting were discussed. Then, current strategies for improving the physical properties of bioinks and for reinforcing bioinks in EBB approaches were introduced, respectively. Notably, we highlighted the applications and effects of current EBB-based bioinks on wound healing, wound scar formation, vascularization and the regeneration of skin appendages (i.e., sweat glands and hair follicles) and discussed the challenges and future perspectives. This review aims to provide an overall view of the applications, challenges and promising solutions about the EBB-based bioinks for cutaneous wound healing and skin regeneration.

The goals and approaches to fluid therapy vary through different stages of resuscitation. This pilot study was designed to test the safety and feasibility of a fluid therapy protocol for the second or optimisation stage of resuscitation in patients with predicted severe acute pancreatitis (SAP).Spontaneously breathing patients with predicted SAP were admitted after initial resuscitation and studied over a 24-h period in a tertiary hospital ward. Objective clinical assessment (OCA; heart rate, mean arterial pressure, urine output, and haematocrit) was done at 0, 4, 8, 12, 18-20, and 24 h. All patients had mini-fluid challenge (MFC; 250 ml intravenous normal saline within 10 min) at 0 h and repeated at 4 and 8 h if OCA score ≥2. Patients who were fluid responsive (10% change in stroke volume after MFC) received 5-10 ml/kg/h, otherwise 1-3 ml/kg/h until the next time point. Passive leg raising test (PLRT) was done at each time point and compared with OCA for assessing volume status and predicting fluid responsiveness.This fluid therapy protocol based on OCA, MFC, and PLRT and designed for the second stage of resuscitation was safe and feasible in spontaneously breathing predicted SAP patients. The PLRT was superior to OCA (at 0 and 8 h) for predicting fluid responsiveness and guiding fluid therapy.This pilot study found that a protocol for intravenous fluid therapy specifically for the second stage of resuscitation in patients with predicted SAP was safe, feasible, and warrants further investigation.

Three signal peptides from α-mating factor (α-MF), inulinase (INU) and native levansucrase (LS) were compared for secretion efficiency of Bacillus subtilis levansucrase SacB-T305A in Pichia pastoris GS115. The first complete secretion of bacterial levansucrase in yeasts under methanol induction was achieved while using α-MF signal. The secreted recombinant Lev(α-MF) proved to be glycosylated by combination of NanoLC-MS/MS and Endo H digestion. Interestingly, glycosylation not only improved significantly the polymerase thermostability, but also reversed the products profiles to favor synthesis of high molecular weight (HMW) levan which accounted for approximately 73 % to total levan-type polysaccharides. It indicated for the first time that the glycosylation of recombinant B. subtilis levansucrase affected significantly the products molecular weight distribution. It also provided a promising enzymatic way to effectively product HMW levan from sucrose resources.

Umbilical cord mesenchymal stem cells (UCMSCs) transplantation has been proposed as a promising treatment modality for myocardial infarction (MI), but the low retention rate remains a considerable challenge. Injectable natural polymer hydrogels with conductivity ability are highly desirable as cell delivery vehicles to repair infarct myocardium and restore the cardiac function. In this work, we developed a hydrogel system based on gelatin methacrylate (GelMA) and oxidized dextran (ODEX) as cell delivery vehicles for MI. And dopamine could be used as a reductant of graphene oxide (GO) to form reductive GO (rGO). By adjusting the amount of rGO, the conductivity of hydrogels with 0.5 mg/mL rGO concentration (≈10−4 S/cm) was similar to that of natural heart tissue. In vitro cell experiments showed that the prepared hydrogels had excellent biocompatibility and cell delivery ability of UCMSCs. More importantly, GelMA-O5/rGO hydrogel could promote UCMSCs growth and proliferation, improve the myocardial differentiation ability of UCMSCs, and up-regulate the expression of cTnI and Cx43. Further in vivo experiments demonstrated that GelMA-O5/rGO/UCMSCs Hydrogel could significantly improve the ejection fraction (EF) of rats and significantly reduce myocardial infarct area compared to PBS group, promote the survival of UCMSCs, enhance the expression level of cTnI and Cx43, and decrease the expression level of caspase-3. The findings of this study suggested that the injectable conductive GelMA-O5/rGO hydrogel encapsulating UCMSCs could improve damaged myocardial tissue and reconstruct myocardial function, which will be a promising therapeutic strategy for cardiac repair.

Micro-/macroangiopathy, neuropathy and prolonged inflammation are common in diabetic wound, however, traditional wound dressing cannot treat these problems in the same time. Herein, we developed a multifunctional hydrogel with promoted angiogenesis, cell proliferation and anti-inflammation ability to treat diabetic wound. The hydrogel was composed of natural polymers, including gelatin and chitosan, which have excellent biocompatibility. Histatin-1 (His-1) was added into the hydrogel to improve the cell adhesion, proliferation and angiogenesis. Besides, polypyrrole based conductive nanoparticles (G-Ppy) were introduced in the hydrogel to enhance the electrical signal conduction between skin and promote the mechanical strength of the hydrogel. The polypyrrole nanoparticles were growth in the chain of methacryloyl grafted gelatin (Gel-MA), leading to a better biocompatibility and water dispersibility. In vivo wound healing experiment proved that the hydrogel accelerated the wound healing rate, down regulation the expression of pro-inflammation factor TNF-α and upregulation the expression of CD31 and α-SMA, indicating the prospects in the application of diabetic wound healing.

Investigation of passenger flight delays with statistical physics has been less focused by previous researchers. We consider the flights as special particles, and take quasi-thermodynamic variables to describe their van der Waals - like gaseous equations. Improved from our former model, we download data of 6 more years (2015–2020) with 20 original ones (1995–2014), and redefine pressure as two average number of departure/arrival flights per airport in a given day. Therefore, we enact an empirical gaseous constant R , and get a new kind of “delayor gases” as the daily average delays per flight at all airports. The approach could be applied to passenger flights of any other countries and different complex systems.

The majority of electric arc injury wounds are deep second-degree or mixed depth wounds. Traditional treatment methods in these types of injuries have many shortcomings. This randomized prospective study evaluated the use of a minimally invasive hydrosurgery system for precise debridement, followed by the application of autologous skin cell suspension prepared utilizing the RECELL® Autologous Cell Harvesting Device (AVITA Medical). Compared with traditional methods, the cases treated with hydrosurgical debridement and autologous skin cell suspension had improved healing times and scar appearance after healing. The combination of these two treatment modalities appears to restore function and appearance for electric arc injuries.

Most of the current approaches for speech enhancement (SE) using deep neural network (DNN) face a number of limitations: they do not exploit information contained in the phase spectrum while their high computational complexity and memory requirements make them unsuited for real-time applications. In this paper, a new phase-aware composite deep neural network (PACDNN) is introduced to address these challenges. Specifically, magnitude processing with spectral mask and phase reconstruction with phase derivative are proposed as key subtasks of the new network to simultaneously enhance the magnitude and phase spectra. Besides, the DNN is meticulously designed to take advantage of strong temporal and spectral dependencies of speech, while its components perform independently and in parallel to speed up the computation. The advantages of the proposed PACDNN model over some well-known DNN-based SE methods are demonstrated through extensive comparative experiments.

Polysaccharides were recovered from red grape pomace by hot water extraction and then subjected to deproteinization, decolorization, fractionization, and characterization. The extraction process conferred a crude polysaccharide yield of 8.45 % (w/w) and the highest decolorization rate of 63.12 % was obtained by soaking the crude polysaccharide solution with 0.20 g/mL HPD-300 macroporous resin for 3 h. Separation with the anionic DEAE Fast Flow column generated four fractions, which were negatively charged according to zeta potential measurement. All the fractions contained uronic acid and their weight-average molecular weights were within the range 2 × 106–4 × 106 Dal. The most abundant fraction GPP-3 was composed of arabinose, xylose, mannose, glucose, and galactose in molar ratio 8.05:1.37:2.85:1.30:7.81 and rhamnose was also present according to FTIR and NMR analysis. AFM observation revealed that aggregation occurred in GPP-3, while the Congo red and β-elimination tests indicated the existence of triple helix and -O- linkage in the fraction. Hence, red grape pomace is a potential source of water-soluble polysaccharides and their bioactivity needs further study.

When using several possible linguistic terms with different weights (represented by probability values) to express preferences, the probability distribution of those linguistic terms is usually hard to be obtained. In this paper, we utilize degree values to reflect the weights of possible linguistic terms and first propose a novel concept called degree-based linguistic term set (DLTS) from the perspective of degree. Then we present a new multi-attribute three-way decision method under the environment of DLTSs. Furthermore, considering that if only one person is involved in decision-making process, it may produce unreasonable or unfair evaluation results. We choose multiple decision-makers to participate in the decision-making process, and propose a multi-attribute group three-way decision method by utilizing the idea of TOPSIS method under the environment of DLTSs. Since the weights of multiple decision-makers (DMs) may be different, we give a method to determine the weights by using the idea of information gain based on the three-way decision results of each decision-maker (DM). Finally, we compare our decision method with an existing decision method, and illustrate the effectiveness of our method through a concrete example.