Electrospray Nano-Micro Composite Sodium Alginate Microspheres with Shape-Adaptive, Antibacterial, and Angiogenic Abilities for Infected Wound Healing.

Nonhealing infectious wounds, characterized by bacterial colonization, wound microenvironment destruction, and shape complexity, present an intractable problem in clinical practice. Inspired by LEGOs, building-block toys that can be assembled into desired shapes, we proposed the use of electrospray nano-micro composite sodium alginate (SA) microspheres with antibacterial and angiogenic properties to fill irregularly shaped wounds instantly. Specifically, porous poly(lactic-co-glycolic acid) (PLGA) microspheres (MSs) encapsulating basic fibroblast growth factor (bFGF) were produced by a water-in-oil-in-water double-emulsion method. Then, bFGF@MSs were blended with the SA solution containing ZIF-8 nanoparticles. The resultant solution was electrosprayed to obtain nano-micro composite microspheres (bFGF@MS/ZIF-8@SAMSs). The composite MSs' size could be regulated by PLGA MS mass proportion and electrospray voltage. Moreover, bFGF, a potent angiogenic agent, and ZIF-8, bactericidal nanoparticles, were found to release from bFGF@MS/ZIF-8@SAMSs in a controlled and sustainable manner, which promoted cell proliferation, migration, and tube formation and killed bacteria. Through experimentation on rat models, bFGF@MS/ZIF-8@SAMSs were revealed to adapt to wound shapes and accelerate infected wound healing because of the synergistic effects of antibacterial and angiogenic abilities. In summation, this study developed a feasible approach to prepare bioactive nano-micro MSs as building blocks that can fill irregularly shaped infected wounds and improve healing.

EFFECTS OF HYPERBARIC OXYGEN THERAPY ON INTESTINAL ISCHEMIA-REPERFUSION AND ITS MECHANISM.

ABSTRACT: Ischemia can cause reversible or irreversible cell or tissue damage, and reperfusion after ischemia not only has no therapeutic effect but also aggravates cell damage. Notably, gut tissue is highly susceptible to ischemia-reperfusion (IR) injury under many adverse health conditions. Intestinal IR (IIR) is an important pathophysiological process in critical clinical diseases. Therefore, it is necessary to identify better therapeutic methods for relieving intestinal ischemia and hypoxia. Hyperbaric oxygenation refers to the intermittent inhalation of 100% oxygen in an environment greater than 1 atm pressure, which can better increase the oxygen level in the tissue and change the inflammatory pathway. Currently, it can have a positive effect on hypoxia and ischemic diseases. Related studies have suggested that hyperbaric oxygen can significantly reduce ischemia-hypoxic injury to the brain, spinal cord, kidney, and myocardium. This article reviews the pathogenesis of IR and the current treatment measures, and further points out that hyperbaric oxygen has a better effect in IR. We found that not only improved hypoxia but also regulated IR induced injury in a certain way. From the perspective of clinical application, these changes and the application of hyperbaric oxygen therapy have important implications for treatment, especially IIR.

The positive impact of the NtTAS14-like1 gene on osmotic stress response in Nicotiana tabacum.

KEY MESSAGE: NtTAS14-like1 enhances osmotic tolerance through coordinately activating the expression of osmotic- and ABA-related genes. Osmotic stress is one of the most important limiting factors for tobacco (Nicotiana tabacum) growth and development. Dehydrin proteins are widely involved in plant adaptation to osmotic stress, but few of these proteins have been functionally characterized in tobacco. Here, to identify genes required for osmotic stress response in tobacco, an encoding dehydrin protein gene NtTAS14-like1 was isolated based on RNA sequence data. The expression of NtTAS14-like1 was obviously induced by mannitol and abscisic acid (ABA) treatments. Knock down of NtTAS14-like1 expression reduced osmotic tolerance, while overexpression of NtTAS14-like1 conferred tolerance to osmotic stress in transgenic tobacco plants, as determined by physiological analysis of the relative electrolyte leakage and malonaldehyde accumulation. Further expression analysis by quantitative real-time PCR indicated that NtTAS14-like1 participates in osmotic stress response possibly through coordinately activating osmotic- and ABA-related genes expression, such as late embryogenesis abundant (NtLEA5), early responsive to dehydration 10C (NtERD10C), calcium-dependent protein kinase 2 (NtCDPK2), ABA-responsive element-binding protein (NtAREB), ABA-responsive element-binding factor 1 (NtABF1), dehydration-responsive element-binding genes (NtDREB2A), xanthoxin dehydrogenase/reductase (NtABA2), ABA-aldehyde oxidase 3 (NtAAO3), 9-cis-epoxycarotenoid dioxygenase (NtNCED3). Together, this study will facilitate to improve our understandings of molecular and functional properties of plant TAS14 proteins and to improve genetic evidence on the involvement of the NtTAS14-like1 in osmotic stress response of tobacco.

Timing of surgical operation for patients with intra-abdominal infection: A systematic review and meta-analysis.

BACKGROUND: Intra-abdominal infections (IAIs) is the most common type of surgical infection, with high associated morbidity and mortality rates. In recent years, due to the use of antibiotics, various drug-resistant bacteria have emerged, making the treatment of abdominal infections more challenging. Early surgical exploration can reduce the mortality of patients with abdominal infection and the occurrence of complications. However, available evidence regarding the optimal timing of IAI surgery is still weak. In study, we compared the effects of operation time on patients with abdominal cavity infection and tried to confirm the best timing of surgery. AIM: To assess the efficacy of early vs delayed surgical exploration in the treatment of IAI, in terms of overall mortality. METHODS: A systematic literature search was performed using PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Ovid, and ScienceDirect. The systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses method. Based on the timing of the surgical operation, we divided the literature into two groups: Early surgery and delayed surgery. For the early and delayed surgery groups, the intervention was performed with and after 12 h of the initial surgical intervention, respectively. The main outcome measure was the mortality rate. The literature search was performed from May 5 to 20, 2021. We also searched the World Health Organization International Clinical Trials Registry Platform search portal and ClinicalTrials.gov on May 20, 2021, for ongoing trials. This study was registered with the International Prospective Register of Systematic Reviews. RESULTS: We identified nine eligible trial comparisons. Early surgical exploration of patients with IAIs (performed within 12 h) has significantly reduced the mortality and complications of patients, improved the survival rate, and shortened the hospital stay. CONCLUSION: Early surgical exploration within 12 h may be more effective for the treatment of IAIs relative to a delayed operation.

Bioinks adapted for in situ bioprinting scenarios of defect sites: a review.

In situ bioprinting provides a reliable solution to the problem of in vitro tissue culture and vascularization by printing tissue directly at the site of injury or defect and maturing the printed tissue using the natural cell microenvironment in vivo. As an emerging field, in situ bioprinting is based on computer-assisted scanning results of the defect site and is able to print cells directly at this site with biomaterials, bioactive factors, and other materials without the need to transfer prefabricated grafts as with traditional in vitro 3D bioprinting methods, and the resulting grafts can accurately adapt to the target defect site. However, one of the important reasons hindering the development of in situ bioprinting is the absence of suitable bioinks. In this review, we will summarize bioinks developed in recent years that can adapt to in situ printing scenarios at the defect site, considering three aspects: the in situ design strategy of bioink, the selection of commonly used biomaterials, and the application of bioprinting to different treatment scenarios.

Comparative physiological and metabolic analyzes of two Italian ryegrass (Lolium multiflorum) cultivars with contrasting salinity tolerance.

Italian ryegrass (Lolium multiflorum) is a widely cultivated forage with high nutritional value and good palatability. Salinity, however, is a negative factor to lessen output and quality in Italian ryegrass. The aim of this study was to elucidate the salt tolerance mechanism of two Italian ryegrass cultivars, 'Abundant' and 'Angus'. Under hydroponic conditions, two cultivars of Italian ryegrass with different salt tolerance were exposed to 0 and 300 mM NaCl solution for 1 week, respectively. The results showed that salt stress decreased relative growth rate and relative water content, especially in salt-sensitive 'Angus'. The salt-tolerant 'Abundant' cultivar alleviated reactive oxygen species (ROS) induced burst and cell damage. However, 'Angus' exhibited a greater activity of superoxide dismutase (SOD) and peroxidase (POD) than 'Abundant'. Additionally, 'Abundant' exhibited higher photosynthetic efficiency than 'Angus' under salt stress condition. Salt treatment significantly increased the Na/K, Na/Mg, and Na/Ca ratios in the leaves and roots of both cultivars, with a pronounced effect in salt-sensitive 'Angus'. The metabolite analysis of leaf polar extracts revealed 41 salt responsive metabolites in both cultivars, mainly consisting of amino acids, organic acids, fatty acids, and sugars. Following exposure to salt conditions, salt-sensitive 'Angus' had a higher level of metabolites and more uniquely upregulated metabolites were detected. Based on these findings, we conclude that the 'Abundant' cultivar emerged as a favorite in saline-alkali soil, while the 'Angus' cultivar is suitable for planting in normal soil. It appears that the high salt tolerance of 'Abundant' is partly to prevent the plant from ionic homeostasis disruption.

Endogenous salicylic acid shows different correlation with baicalin and baicalein in the medicinal plant Scutellaria baicalensis Georgi subjected to stress and exogenous salicylic acid.

Salicylic acid (SA) is synthesized via the phenylalanine lyase (PAL) and isochorismate synthase (ICS) pathways and can influence the stress response in plants by regulating certain secondary metabolites. However, the association between SA and particular secondary metabolites in the Chinese medicinal plant Scutellaria baicalensis Georgi is unclear. To elucidate the association between SA and the secondary metabolites baicalin and baicalein, which constitute the primary effective components of S. baicalensis, we subjected seedlings to drought and salt stress and exogenous SA treatment in a laboratory setting and tested the expression of PAL and ICS, as well as the content of free SA (FSA), total SA (TSA), baicalin, and baicalein. We also assessed the correlation of FSA and TSA with PAL and ICS, and with baicalin and baicalein accumulation, respectively. The results indicated that both FSA and TSA were positively correlated with PAL, ICS, and baicalin, but negatively correlated with baicalein. The findings of this study improve our understanding of the manner in which SA regulates secondary metabolites in S. baicalensis.