3D skin bioprinting as promising therapeutic strategy for radiation-associated skin injuries.

Both cutaneous radiation injury and radiation combined injury (RCI) could have serious skin traumas, which are collectively referred to as radiation-associated skin injuries in this paper. These two types of skin injuries require special managements of wounds, and the therapeutic effects still need to be further improved. Cutaneous radiation injuries are common in both radiotherapy patients and victims of radioactive source accidents, which could lead to skin necrosis and ulcers in serious conditions. At present, there are still many challenges in management of cutaneous radiation injuries including early diagnosis, lesion assessment, and treatment prognosis. Radiation combined injuries are special and important issues in severe nuclear accidents, which often accompanied by serious skin traumas. Mass victims of RCI would be the focus of public health concern. Three-dimensional (3D) bioprinting, as a versatile and favourable technique, offers effective approaches to fabricate biomimetic architectures with bioactivity, which provides potentials for resolve the challenges in treating radiation-associated skin injuries. Combining with the cutting-edge advances in 3D skin bioprinting, the authors analyse the damage characteristics of skin wounds in both cutaneous radiation injury and RCI and look forward to the potential value of 3D skin bioprinting for the treatments of radiation-associated skin injuries.

Overall Description and Predictors of Disruptive Behavior Toward Nurses in the Perioperative Arena.

PURPOSE: To investigate the prevalence, characteristics, causes, consequences, and predictors of and responses to disruptive behavior toward nurses in the perioperative arena. DESIGN: A cross-sectional design using a network questionnaire platform. METHODS: Nurses in the perioperative arena were recruited online in March 2020. Data on disruptive behavior toward nurses in the past 6 months and nurses' sociodemographic and environmental factors were collected. FINDINGS: Nurses (N = 496) responded validly to the survey. In total, 82.1% of participants experienced disruptive behavior. Assignment of overwhelming workloads and verbal aggression were the most common behaviors, and surgeons were the major perpetrators. Perpetrators' intrapersonal issues were the most commonly perceived causes. A positive strategy was the most common strategy adopted by participants. Further, 80.8% of participants recounted their negative experiences, and more than half of respondents (59.9%) talked with their nursing colleagues. Nearly half of respondents (45.9%) did not report disruptive behavior. Negative emotions as an immediate effect were reported by 53.1% of the participants, and the most common long-term impact was decreased passion for work. Middle age, job position, practice environment, and system help were risk factors for experiencing disruptive behavior. CONCLUSIONS: The prevalence of disruptive behavior toward nurses in the perioperative arena is high, and its ramifications should not be ignored. Health care institutions should urgently implement intervention strategies to reduce disruptive behavior toward nurses.

Effects of Peppermint Essential Oil on Learning and Memory Ability in APP/PS1 Transgenic Mice.

OBJECTIVE: To explore the effect and mechanism of peppermint essential oil on learning and memory ability of APP/PS1 transgenic mice. METHODS: Morris water maze test and shuttle box test were used to explore the changes in learning and memory ability of APP/PS1 transgenic mice after sniffing essential oil. The cellular status of neurons in the hippocampal CA1 region of the right hemisphere, Aß deposition, oxidative stress level, and serum metabonomics were detected to explore its mechanism. RESULTS: Sniffing peppermint essential oil can improve the learning and memory ability of APP/PS1 transgenic mice. Compared with the model group, the state of neurons in the hippocampal CA1 region of the peppermint essential oil group returned to normal, and the deposition of Aß decreased. The MDA of brain tissue decreased significantly, and the activity of SOD and GSH-PX increased significantly to the normal level. According to the results of metabonomics, it is speculated that peppermint essential oil may improve cognitive function in AD by regulating arginine and proline metabolism, inositol phosphate metabolism, and cysteine and methionine metabolism.

A Comprehensive Protocol to Prevent Brachial Plexus Injury During Ankylosing Spondylitis Surgery.

PURPOSE: This article describes a comprehensive protocol to protect the brachial plexus when performing pedicle subtraction osteotomy for ankylosing spondylitis patients with thoracolumbar kyphosis. DESIGN: A descriptive study was conducted. METHODS: Records of 101 cases from October 2013 to December 2016 were retrospectively audited. The protocol included five items: (1) preoperative assessment of motion range and nerve function of limbs and trunks; (2) preoperative positioning according to the assessment results; (3) intra-operative somatosensory evoked potential and blood pressure monitoring; (4) intra-operative repositioning according to the monitoring alarm signals; and (5) postoperative neurological function check. FINDINGS: Five patients showed impending brachial plexus injury indicators, including two who had a decrease in blood pressure and three who had a decrease in the amplitude of somatosensory evoked potential. After adjustment of position and soft pads, one patient had brachial plexus injury (0.99%) and the recovery time was 2 weeks. CONCLUSIONS: With this comprehensive strategy, the brachial plexus could be effectively protected during the surgery.

New insights into the mechanism and kinetics of the addition reaction of unsaturated Criegee intermediates to CF3COOH and tropospheric implications.

In this work, we have investigated the mechanism, thermochemistry and kinetics of the reaction of syn-cis-CH2RzCRyCO+O- (where Rz, Ry = H, CH3-) unsaturated Criegee intermediates (CIs) with CF3COOH using quantum chemical methods. The rate coefficients for the barrierless reactions were calculated using variable reaction coordinate variational transition state theory (VRC-VTST). For the syn-cis-CH2RzCRyCO+O- conformation in which conjugated CC and CO double bonds are aligned with each other, we propose a new pathway for the unidirectional addition of an OC-OH molecule (CF3COOH) to the CC double bond of syn-cis-CH2RzCRyCO+O-. The rate coefficient for the 1,4-CC addition reaction at 298 K is ∼10-10 to 10-11 cm3 s-1, resulting in the formation of CF3C(O)OCH2CRzRyCOOH trifluoroacetate alkyl allyl hydroperoxide (TFAAAH) as a new transitory adduct. It can act as a precursor for the formation of secondary organic aerosols (SOAs). This novel TFAAAH hydroperoxide was identified through a detailed quantum chemical study of the 1,4-addition mechanism and will provide new insights into the significance of the 1,4-addition reaction of unsaturated Cls with trace tropospheric gases on -CRzCH2 vinyl carbon atoms.

Formation mechanism of Pickering emulsion gels stabilized by proanthocyanidin particles: Experimental and molecular dynamics studies.

The feasibility of constructing a Pickering emulsion gel with proanthocyanidin particles (PAP) was evaluated in this study, and the related mechanism was revealed by combining instrumental characterization with molecular dynamics simulation. The results showed that PAP was composed of nano/micron spherical particles or their fragments, which had excellent wettability. Suitable PAP addition amount (w, ≥1%) and oil volume fraction (φ, 40-90 %) were beneficial to the formation of stable Pickering emulsion gel. The oil droplet size of gel was inversely proportional to w and φ. The mechanical parameters (gel strength, loss modulus, and storage modulus) were positively correlated with w and φ. Molecular dynamics simulation indicated that the proanthocyanidin molecules in the oil-water system could spontaneously reside and aggregate at the interface, and their interactions with water and oil reduced interfacial tension, which was consistent with the experimental results. This study provides a reference for other polyphenol-based Pickering emulsions.

Effect of citric acid esterification on the structure and physicochemical properties of tigernut starch.

In this work, esterified tigernut starch with citric acid (ETSC) was prepared for the first time, and its structure, in vitro digestibility, and Pickering emulsifying capacity were investigated. The formation of ETSC was confirmed by SEM (Scanning electron microscopy), XRD (X-ray diffraction), FTIR (Fourier-transform infrared spectroscopy), and solid-state 13C NMR (Nuclear magnetic resonance), and the citric acid dosage in the preparation process was positively correlated with the degree of substitution (DS) of ETSC. With an increase in DS, the solubility and swelling power of ETSC decreased, the crystallinity degree declined, and the proportion of resistant starch (RS) increased rapidly. The increase in DS could also enhance the wettability of ETSC, thus improving the Pickering emulsifying ability of ETSC. The high ETSC concentration (c) and suitable oil phase volume ratio (φ) of the Pickering emulsion were beneficial to its formation and stability. Moreover, the macroscopic viscosity index (MVI) and elastic index (EI) of the emulsion were also positively related to the DS of ETSC.

Metabonomics Study in Mice With Learning and Memory Impairment on the Intervention of Essential Oil Extracted From Cinnamomum camphora Chvar. Borneol.

Our objective was to explore the mechanism of essential oil that was extracted from Cinnamomum camphora chvar. Borneol (Borneol essential oil) for improving learning and memory impairment in mice. Brain tissue and plasma samples of a normal group, a model group, a Borneol essential oil group and a reference group were detected using gas chromatography time-of-flight mass spectrometry (GC-TOFMS) in order to find differential metabolites and analyze metabolic pathways. Results showed that there were 11 different metabolites --including glycine and azelaic acid --in plasma samples, and that there were 26 different metabolites--including adenine and aspartic acid --in brain tissue samples. These metabolites are involved in phenylalanine, tyrosine, and tryptophan biosynthesis, phenylalanine metabolism, alanine, aspartate and glutamate metabolism, arginine biosynthesis, beta-alanine metabolism, glyoxylate acid and dicarboxylate metabolism, and aminoacyl-tRNA biosynthesis. Thus, Borneol essential oil may improve learning and memory impairment by regulating amino acid metabolism and/or neurotransmitter changes.

Nitrite accumulation, denitrification kinetic and microbial evolution in the partial denitrification process: The combined effects of carbon source and nitrate concentration.

The combined effects of carbon source (HAc, HPr, Glu, Glu + HAc) and nitrate concentration (40, 80 mg/L labeling as R40, R80) on partial denitrification (PD) were discussed at C/N ratio of 2.5 (COD = 100, 200 mg/L). The optimal NO2--N and NTR reached to 67.03 mg/L, 99.14% in HAc-R80 system, and denitrification kinetics revealed the same conclusion, corresponding to higher COD utilization rate (CUR: 58.46 mgCOD/(gVSS·h)), nitrate reduction rate (NaRR: 29.94 mgN/(gVSS·h)) and nitrite accumulation rate (NiAR: 29.68 mgN/(gVSS·h)). The preference order was HAc > HPr > Glu + HAc > Glu in both R40 and R80 systems due to different metabolic pathways, however, the NO2--N accumulation and kinetic parameters of R80 group were dramatically higher than those in R40 for the same carbon source. The R80 group facilitated more concentrated biodiversity (607-808 OTUs) with Terrimonas and norank_f_Saprospiraceae responsible for high NO2--N accumulation in HAc and HPr served systems, while norank_f_norank_o_Saccharimonadales and OLB13 dominated the Glu containing systems.