Rapid detection of pathogens of peritoneal dialysis-related peritonitis, especially in patients who have taken antibiotics, using metagenomic next-generation sequencing: a pilot study.

INTRODUCTION: Peritoneal dialysis (PD)-related peritonitis is a serious complication of PD. Improving the diagnostic rate of peritonitis pathogens may substantially benefit peritonitis patients. METHODS: The study was conducted in the People's Liberation Army (PLA) General Hospital from 1 June 2021 to 31 May 2022. Information about peritonitis, culture and metagenomic next-generation sequencing (mNGS) results and so on were collected. Patients were divided into antibiotic-use and antibiotic-free groups. The culture and mNGS results were compared using the paired χ2 test. RESULTS: Data from 26 patients with peritonitis were collected. 50% of the patients had used antibiotics before samples were obtained (antibiotic-use group). The positivity rate using culture was 92.3% (12 cases) in the antibiotic-free group and 38.5% (5 cases) in the antibiotic-use group (p = 0.011). However, the positivity rate using mNGS was 92.3% (12 cases) regardless of whether antibiotics were used (p = 1.000). After revising the mNGS results, the positivity rate was 84.6% (11 cases) in both groups (p = 1.000). A significant difference between culture and mNGS results of all groups was observed (p = 0.039). The difference no matter between culture and mNGS (p = 0.016) or between culture and modified mNGS (p = 0.031) of the antibiotic-use group was observed. CONCLUSION: For patients with PD-related peritonitis who previously received antibiotics, mNGS is suggested. For other patients, mNGS testing can be performed, but the results should be interpreted with caution. Much more research should be done to identify a powerful and ideal tool to detect pathogens underlying PD-related peritonitis.

Application of Skin-stretching Device for Closing Scalp Defect.

BACKGROUND: The scalp defect was a clinical common constructive challenge. This research verified the efficacy of the skin-stretching device in the treatment of scalp defect and assessed the associated complications. METHODS: The clinical data of 12 patients with scalp defect treated with skin-stretching device from January 2020 to January 2021 were collected. We used EASApprox skin-stretching device for the treatment of scalp defect. We described a detailed reconstruction procedure for this treatment. We collected the site, distance from wound edge and other characteristics of the wound, and recorded the number of stretching cycles, operation time, closed state, healing time, and observed postoperative complications and wound healing status. RESULTS: In this research, the scalp defect was mainly caused by pressure ulcer, and mainly located in the parietooccipital site. The average distance from wound edge was 3.2 cm, the average stretching cycles was 4.2 times during the operation, and the average operation time was 43.5 minutes. Ten patients were directly sutured after stretching, and 2 patients underwent first-stage stretching to reduce the wound. The average time of wound healing was 13.5 days. Postoperative follow-up of 3 months, no patients had wound tear, necrosis, 1 patient suffered from wound exudation and infection due to poor nutrition. Skin function and final scar was acceptable. CONCLUSION: The treatment of skin-stretching device was effective for scalp defect and has the advantages of convenient operation, acceptable functional results, without severe complications. In addition to traditional treatment, this was a promising treatment. However, more clinical and preclinical research of the skin-stretching device were required.

Ferritinophagy is Involved in Experimental Subarachnoid Hemorrhage-Induced Neuronal Ferroptosis.

Ferroptosis is a novel form of regulated cell death involved in the pathophysiological process of experimental subarachnoid hemorrhage (SAH), but how neuronal ferroptosis occurs remains unknown. In this study, we report that SAH-induced ferroptosis is macroautophagy/autophagy dependent because the inhibition of autophagy by knocking out autophagy-related gene 5 (ATG5) apparently mitigated SAH-induced ferroptosis. We created an experimental SAH model in Sprague-Dawley rats to determine the possible mechanism. We found that SAH can trigger neuronal ferroptosis, as evidenced by the disruption of iron homeostasis, elevation of intracellular lipid peroxidation (LPO) and decreased expression of ferroptosis-protective proteins. Then, we inhibited autophagy by ATG5 gene knockout, showing that autophagy inhibition can reduce the intracellular iron level and LPO, improve the expression of ferroptosis-protective proteins, and subsequently alleviate SAH-induced cell death. Additionally, autophagy inhibition also attenuated SAH prognostic indicators, such as brain edema, blood-brain barrier permeability, and neurological deficits. These findings not only present an opinion that SAH triggers neuronal ferroptosis via activation of ferritinophagy but also indicate that regulating ferritinophagy and maintaining iron homeostasis could provide clues for the prevention of early brain injury.

Basic Fibroblast Growth Factor (bFGF) Protects the Blood-Brain Barrier by Binding of FGFR1 and Activating the ERK Signaling Pathway After Intra-Abdominal Hypertension and Traumatic Brain Injury.

BACKGROUND Intra-abdominal hypertension (IAH) is associated with high morbidity and mortality. IAH leads to intra-abdominal tissue damage and causes dysfunction in distal organs such as the brain. The effect of a combined injury due to IAH and traumatic brain injury (TBI) on the integrity of the blood-brain barrier (BBB) has not been investigated. MATERIAL AND METHODS Intracranial pressure (ICP) monitoring, brain water content, EB permeability detection, immunofluorescence staining, real-time PCR, and Western blot analysis were used to examine the effects of IAH and TBI on the BBB in rats, and to characterize the protective effects of basic fibroblast growth factor (bFGF) on combined injury-induced BBB damage. RESULTS Combined injury from IAH and TBI to the BBB resulted in brain edema and increased intracranial pressure. The effects of bFGF on alleviating the rat BBB injuries were determined, indicating that bFGF regulated the expression levels of the tight junction (TJ), adhesion junction (AJ), matrix metalloproteinase (MMP), and IL-1ß, as well as reduced BBB permeability, brain edema, and intracranial pressure. Moreover, the FGFR1 antagonist PD 173074 and the ERK antagonist PD 98059 decreased the protective effects of bFGF. CONCLUSIONS bFGF effectively protected the BBB from damage caused by combined injury from IAH and TBI, and binding of FGFR1 and activation of the ERK signaling pathway was involved in these effects.

Percutaneous insertion of peritoneal dialysis catheter is a safe and effective technique irrespective of BMI.

BACKGROUND: A large body mass index (BMI) has been considered as a relative contraindication for percutaneous catheter insertion, although this technique has many advantages. Up to now, there are few studies on peritoneal catheter placement and obesity. The aim of this study was to determine whether patients with large BMI can also choose the percutaneous technique for peritoneal dialysis catheter insertion. METHODS: One hundred eighty seven consecutive patients underwent peritoneal catheter insertions in the Chinese PLA General Hospital between January 1, 2015 and December 31, 2016, with 178 eligible cases being included in the analysis. Two groups were created based on the catheter insertion techniques, the percutaneous group (group P) and the surgical group (group S). Subgroups were created according to BMI > 28 or ≤ 28. The outcomes included catheter related complications and catheter survival. RESULTS: Total infectious complication rates were significantly lower in group P than in group S. There were no significant differences in peritonitis rate between group P and group S (1.20% vs. 3.16% with P = 0.71 in early stage, and 4.82% vs. 11.58% with P = 0.11 in late stage). All other measured complications were similar between the two groups. Though the one-year infection-free catheter survival in group P was 7.5% higher than group S, the difference was not significant. The one-year dysfunction-free catheter survival, one-year dysfunction-and-infection-free catheter survival, and overall catheter survival were similar between the two groups. Subgroup analyses showed a superior one-year infection-free catheter survival of percutaneous technique in patients with BMI > 28, which was confirmed by Kaplan-Meier analysis. CONCLUSIONS: Despite the challenges that may be encountered with patients who have a large BMI, the percutaneous technique seems to be a safe and effective approach to placing a peritoneal dialysis catheter.

Perioperative management strategy of severe traumatic brain injury during the outbreak of COVID-19.

Since December 2019, a pneumonia caused by a new coronavirus, i.e. COVID-19 occurred in Wuhan, Hubei Province, China. Although the epidemic in China has been bought under control, the global COVID-19 situation is still grim. Severe traumatic brain injury (TBI), as one of critical conditions in the department of neurosurgery, requires an early and effective treatment, especially surgery. There were currently no reliable guidelines on how to perform perioperative protection in TBI patients with suspected or confirmed coronavirus infection. According to the corresponding treatment regulations and guidelines issued by the authorities, we summarized the management strategy of TBI patients in perioperative period during the COVID-19 outbreak based on medical and nursing practice, in order to provide a reference for clinicians.

Risk factors associated with the progression of extra-axial hematoma in the original frontotemporoparietal site after contralateral decompressive surgery in traumatic brain injury patients.

PURPOSE: To introduced our experience with progressive extra-axial hematoma (EAH) in the original frontotemporoparietal (FTP) site after contralateral decompressive surgery (CDS) in traumatic brain injury patients and discuss the risk factors associated with this dangerous situation. METHODS: This retrospective study was conducted on 941 patients with moderate or severe TBI treated in Daping Hospital, Army Medical University, Chongqing, China in a period over 5 years (2013-2017). Only patients with bilateral lesion, the contralateral side being the dominant lesion, and decompressive surgery on the contralateral side conducted firstly were included. Patients were exclude if (1) they underwent bilateral decompression or neurosurgery at the original location firstly; (2) although surgery was performed first on the contralateral side, surgery was done again at the contralateral side due to re-bleeding or complications; (3) patients younger than 18 years or older than 80 years; and (4) patients with other significant organ injury or severe disorder or those with abnormal coagulation profiles. Clinical and radiographic variables reviewed were demographic data, trauma mechanisms, neurological condition assessed by Glasgow coma scale (GCS) score at admission, pupil size and reactivity, use of mannitol, time interval from trauma to surgery, Rotterdam CT classification, type and volume of EAH, presence of a skull fracture overlying the EAH, status of basal cistern, size of midline shift, associated brain lesions and types, etc. Patients were followed-up for at least 6 months and the outcome was graded by Glasgow outcome scale (GOS) score as favorable (scores of 4-5) and unfavorable (scores of 1-3). Student's t-test was adopted for quantitative variables while Pearson Chi-squared test or Fisher's exact test for categorical variables. Multivariate logistic regression analysis was also applied to estimate the significance of risk factors. RESULTS: Initially 186 patients (19.8%) with original impact locations at the FTP site and underwent surgery were selected. Among them, 66 met the inclusion and exclusion criteria. But only 50 patients were included because the data of the other 16 patients were incomplete. Progressive EAH developed at the original FTP site in 11 patients after the treatment of, with an incidence of 22%. Therefore the other 39 patients were classified as the control group. Multivariate logistic regression analysis showed that both the volume of the original hematoma and the absence of an apparent midline shift were significant predictors of hematoma progression after decompressive surgery. Patients with fracture at the original impact site had a higher incidence of progressive EAH after CDS, however this factor was not an important predictor in the multivariate model. We also found that patients with progressive EAH had a similar favorable outcome with control group. CONCLUSION: Progressive EAH is correlated with several variables, such as hematoma volumes ≥10 mL at the original impact location and the absence of an apparent midline shift (<5 mm). Although progressive EAH is devastating, timely diagnosis with computed tomography scans and immediate evacuation of the progressive hematoma can yield a favorable result.

Basic Fibroblast Growth Factor Reduces Permeability and Apoptosis of Human Brain Microvascular Endothelial Cells in Response to Oxygen and Glucose Deprivation Followed by Reoxygenation via the Fibroblast Growth Factor Receptor 1 (FGFR1)/ERK Pathway.

BACKGROUND Disruption of the blood-brain barrier (BBB) is a mechanism in the pathogenesis of traumatic brain injury. Basic fibroblast growth factor (bFGF) is expressed in angiogenesis, neurogenesis, and neuronal survival. This study aimed to investigate the role of bFGF in vitro in human brain microvascular endothelial cells (HBMECs) challenged by oxygen-glucose deprivation/reperfusion (OGD/R). MATERIAL AND METHODS HBMECs were cultured in glucose-free medium and an environment with <0.5% oxygen in an anaerobic chamber. Immunocytochemistry, Western blot, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) were used to measure the protein and mRNA expression levels of bFGF, tight junction, adherens junction, apoptotic proteins, and matrix metalloproteinases (MMPs). The effects of bFGF on the viability of HBMECs was evaluated using the cell counting kit-8 (CCK-8) assay. Cell apoptosis was evaluated using the TUNEL assay, and endothelial permeability was quantified using a transwell migration assay with fluorescein isothiocyanate (FITC) conjugated with dextran. The effects of bFGF were evaluated following inhibition of fibroblast growth factor receptor 1 (FGFR1) with PD173074 and inhibition of ERK with PD98059. RESULTS Following OGD/R of HBMECs, bFGF significantly reduced cell permeability and apoptosis and significantly inhibited the down-regulation of the expressions of proteins associated with tight junctions, adherens junctions, apoptosis and matrix metalloproteinases (MMPs). The effects of bFGF were mediated by the activation of FGFR1 and ERK, as they were blocked by FGFR1 and ERK inhibitors. CONCLUSIONS Permeability and apoptosis of HBMECs challenged by OGD/R were reduced by bFGF by activation of the FGFR1 and the ERK pathway.

Dissipation, residues, and risk assessment of imidacloprid in Zizania latifolia and purple sweet potato under field conditions using LC-MS/MS.

A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2-5.5 days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005-0.120 mg kg-1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields.

Residues, dissipation kinetics, and dietary intake risk assessment of two fungicides in grape and soil.

The residue behavior and dietary intake risk of two fungicides (dimethomorph and pyraclostrobin) in grape (Vitis vinifera L.) were investigated from field trials. A modified quick, easy, cheap, effective, rugged, and safe method for simultaneously determining dimethomorph and pyraclostrobin residues in grape and soil was established using high performance liquid chromatography-tandem mass spectrometry. The average recoveries of dimethomorph and pyraclostrobin in the grape and soil matrices varied from 76.88% to 97.05%, with relative standard deviations of 1.73%-10.38%. The degradation half-lives of dimethomorph and pyraclostrobin were 7.3-12.0 days and 3.6-7.0 days in grape and soil, respectively. The terminal residues of dimethomorph and pyraclostrobin in the two matrices were 0.05-0.87 mg/kg. For dietary exposure risk assessments, all of the hazard quotient and hazard quotient index values were below 100%, which indicated that the suspending agents of dimethomorph and pyraclostrobin were sprayed on grape at the recommended dosages with no significant potential risks for Chinese consumers. This study provides a reference for analytically evaluating residual degradation behavior and dietary intake risk of two fungicides under field conditions.

Simultaneous determination of residues of thiamethoxam and its metabolite clothianidin in tobacco leaf and soil using liquid chromatography-tandem mass spectrometry.

A simple analytical method was developed to simultaneously determine thiamethoxam and its metabolite, clothianidin, in fresh tobacco leaf, soil and cured tobacco leaf using liquid chromatography with tandem mass spectrometry. Thiamethoxam and clothianidin in tobacco and soil samples were extracted with acetonitrile containing 0.1% formic acid and purified using an NH2 -SPE column. The optimized method provided good linearity with coefficients of determination R2 ≥ 0.9981. The limits of detection and quantification were between 0.006-0.12 and 0.02-0.4 mg/kg, respectively. Intra- and inter-day recovery assays were used to validate the established method. The average recoveries of thiamethoxam and clothianidin in fresh tobacco leaf, soil and cured tobacco leaf were 75.04-100.47%, 75.86-86.40% and 89.83-99.39%, respectively. The intra- and inter-day relative standard deviations were all <9%. The developed method was successfully applied for the analysis of thiamethoxam and clothianidin residues in actual tobacco and soil samples. The results indicated that the established method met the requirements for the analysis of trace amounts of thiamethoxam and clothianidin in fresh tobacco leaf, soil and cured tobacco leaf.

Dissipation, residues and risk assessment of spirotetramat and its four metabolites in citrus and soil under field conditions by LC-MS/MS.

A modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the simultaneous determination of spirotetramat and its four metabolite residues in citrus, peel, pulp and soil was developed and validated by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The samples were extracted with acetonitrile (1%, glacial acetic acid, v/v) and purified using primary secondary amine and octadecylsilane. The limit of detection was 0.01-0.13 mg/kg, whereas that of quantification was 0.02-0.40 mg/kg for spirotetramat and its metabolites. The average recoveries of spirotetramat, spirotetramat-enol, spirotetramat-mono-hydroxy, spirotetramat-enol-glucoside and spirotetramat-ketohydroxy in all matrices were 73.33-107.91%, 75.93-114.85%, 76.44-100.78%, 71.46-103.19% and 73.08-105.27%, respectively, with relative standard deviations < 12.32%. The dissipation dynamics of spirotetramat in citrus and soil followed first-order kinetics, with half-lives of 2.3-8.5 days in the three sampling locations. The terminal residues of spirotetramat in four matrices at the three locations were measured below the 1.0 mg/kg maximum residue limit set by China, and residues were found to be concentrated on the peel. The risk assessment of citrus was evaluated using risk quotients. The risk quotient values were found to be significantly <1, suggesting that the risk to human health was negligible when using the recommended doses of spirotetramat in citrus. These results could provide guidance for the safe and proper application of spirotetramat in citrus in China.

A novel framework for urban flood risk assessment: Multiple perspectives and causal analysis.

Risk assessment and adaptation have become key focuses in the examination of urban flooding risk. In recent decades, global climate change has resulted in a high incidence of extreme weather events, notably flooding. This study introduces a spatial multi-indicator model developed for assessing flood risk at the urban agglomeration scale. A crucial addition to the model is the incorporation of an adaptive capacity within the IPCC risk framework. The model systematically considers various flood risk indicators related to the economic, social, and geographic environments of the central and southern Liaoning urban agglomeration (CSLN). It generates a spatial distribution map of integrated flood risk for multiple scenario combinations. Furthermore, the intricate relationship between different risk indicators and flood risk was analyzed using correlation analysis and the Light Gradient Boosting Machine model (Light GBM). The findings reveal notable variations in flood risk under different scenarios. The inclusion of vulnerability indicators increased flood risk by 33 %, while the subsequent inclusion of adaptive indicators decreased flood risk by 45 %. Dense populations and assets contribute to high flood risk, while adaptive capacity significantly mitigates urban flood risk. The framework adopted in this paper can be applied to other areas where urban agglomeration-scale flood risk assessment is needed, and can contribute to advancing scientific research on flood forecasting and mitigation.

A dynamically cross-linked catechol-grafted chitosan/gelatin hydrogel dressing synergised with photothermal therapy and baicalin reduces wound infection and accelerates wound healing.

Superior multifunctional hydrogel dressings are of considerable interest in wound healing. In clinical practice, it is useful to investigate hydrogel dressings that offer multifunctional benefits to expedite the process of wound healing. In this study, Catechol-grafted Chitosan, Gelatin, and Fe3+ as substrates to construct a hydrogel network. The network was dynamically cross-linked to form Ccg@Fe hydrogel substrate. Fe3O4 nanoparticles and baicalin, which possess antimicrobial and anti-inflammatory properties, were loaded onto the substrate to form a photothermal antibacterial composite hydrogel dressing (Ccg@Fe/Bai@Fe3O4 NPs). The Ccg@Fe hydrogel was characterised using Fourier transform infrared spectroscopy (FTIR) and Ultraviolet-visible spectrophotometry (UV-Vis). The morphological, mechanical, and adhesion properties of the hydrogel were determined using scanning electron microscopy (SEM) and a universal testing machine. The hydrogel's swelling, hemostasis, and self-healing properties were also evaluated. Additionally, the study determined the release rate of hydrogel-loaded antimicrobial and anti-inflammatory Baicalin (Ccg@Fe/Bai) and evaluated the photothermal antimicrobial properties of hydrogel-loaded Fe3O4 nanoparticles (Ccg@Fe/Bai@Fe3O4 NPs) through synergistic photothermal therapy (PTT). Histological staining of mice skin wound tissues using Masson and H&E revealed that the Ccg@Fe/Bai@Fe3O4 NPs hydrogel dressing demonstrated potential healing ability with the aid of PTT. The study suggests that this multifunctional hydrogel dressing has great potential for wound healing.

Investigation of Cement Prepared with Microencapsulated Microorganisms.

Cracks in underground rock masses cause gas leakage, seepage, and water inflow. To realize calcium carbonate deposition and mineralization filling in rock cracks, microencapsulated bacterial spores were prepared by an oil phase separation method. To optimize the microorganism growth conditions, the effects of microcapsules with various pHs, particle sizes, and amounts on microcrack self-healing were investigated through an orthogonal test, and the best conditions for repairing the cracks using microencapsulated Bacillus sphaericus were obtained. Infrared analysis and scanning electron microscopy were used to observe the morphological characteristics and coating performance of the microcapsules. The results showed that the microcapsules contained functional groups in the core and wall materials. The surfaces of the microcapsules prepared by the test were rough, which was beneficial for adhesion onto the fracture surface. X-ray diffraction analysis, X-ray photoelectron spectroscopy, and thermal analysis were conducted. The results showed that the microcapsules with pH = 8 and a particle size of 100 µm had the highest thermal decomposition temperature and the best thermal stability. The elements of the core and wall materials were detected in the microcapsules, and the coating had a beneficial effect. The compression and acoustic emission tests of the specimens embedding microbial capsules with different contents under different working conditions revealed that the two fractures of the specimen were due to the rupture of the microcapsule and the rupture of the rock specimen, indicating the best mechanical triggering properties and compressive properties of the microcapsule.

Management of Primary Brainstem Hemorrhage: A Review of Outcome Prediction, Surgical Treatment, and Animal Model.

Primary brainstem hemorrhage (PBH) has the worst prognosis of all types of intracerebral hemorrhage. Currently, the management of PBH is controversial. Hematoma classification, scoring systems, and electrophysiological monitoring are critical for predicting the outcome of PBH. Surgery may be an effective treatment for PBH. Clinical studies have emphasized the importance of animal models for understanding the pathogenesis and pathological mechanisms of PBH. In this study, combined with recent studies, the outcome prediction, surgical treatment, and animal models of PBH were reviewed.

Micromechanism Analysis of Surfactant Wetting of Coal Based on 13C NMR Experiments.

With the gradual improvement in coal mine mechanization and automation, the dust concentration at production sites is increasing significantly as the production efficiency improves, which not only poses a substantial threat to the occupational safety and health of workers but also affects the safe production and social stability of mines. At present, wet dust removal is the most economical and effective technical dust removal measure. However, most coal seams in China have poor wettability, unclear microscopic wetting mechanisms, and poor dust removal effects. Therefore, based on experiments and numerical analysis, this paper qualitatively studies the influencing factors of surfactants on coal wettability and quantitatively constructs an innovative evaluation model of the influence of the microstructure of coal and surfactants on wettability. First, based on 13C NMR experiments, the structural parameters of coal and several surfactants were obtained. Second, the wettability relationship between the coal and the surfactants was determined by optical titration, and the key factors affecting the wettability of coal dust and the wettability of the surfactants were selected. Then, using numerical analysis and function fitting analysis and combining the structural parameters with the coal wetting results, the relationship between the microstructure of the surfactants on different kinds of coal and the wettability of the coal samples was established. The results show that the ether group, the phenol or aromatic ether carbon, the fatty methyl group, and the aromatic methyl group in the surfactants have a substantial influence on the wettability. The research results can provide scientific guidance for the development of efficient and environmentally friendly compound dust suppressants to realize clean production in mines.

Synthesis and Characterization of a Multifunctional Sustained-Release Organic-Inorganic Hybrid Microcapsule with Self-Healing and Flame-Retardancy Properties.

As their service life increases, cement-based materials inevitably undergo microcracking and local damage. In response to this problem, this study used phacoemulsification-solvent volatilization to prepare a multifunctional sustained-release microcapsule (SFRM) with self-healing and flame-retardant characteristics. The synthesis of SFRM is based on the modification of ethyl cellulose with nano-SiO2 particles and cross-linking with a silane coupling agent to form an organic-inorganic hybrid wall material. The epoxy resin is blended with hexaphenoxy cyclotriphosphazene (HPCTP) to form a composite core emulsion. The surface morphology, particle size distribution, core-shell composition, and thermal stability of SFRM were analyzed via scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), Malvern, Fourier-transform infrared (FT-IR), and TD-DSC-DTG. It is concluded that SFRM was successfully synthesized with superior particle size distribution and thermal stability. When the ratio of SiO2 solution and EC alcohol solution reached 1:2, the particle size distribution of the microcapsules was 30-190 µm, and the D50 decreased to 70 µm. The core material content, slow-release performance, and flame retardancy of SFRM were measured using a UV-1800 spectrophotometer and Hartmann tubes, and the compressive and repair properties of SFRM were evaluated by uniaxial compression tests. The results demonstrate that SFRM has satisfactory slow-release and flame-retardancy properties, the LC is 67%, and the first-order kinetic model shows the best fit and conforms to the non-Fickian diffusion mechanism. The SFRM repair rate can reach approximately 61%. This is of substantial significance to the field of self-repairing cement-based materials.

Regulation of pathophysiological and tissue regenerative functions of MSCs mediated via the WNT signaling pathway (Review).

Tissues have remarkable natural capabilities to regenerate for the purpose of physiological turnover and repair of damage. Adult mesenchymal stem cells (MSCs) are well known for their unique self­renewal ability, pluripotency, homing potential, paracrine effects and immunomodulation. Advanced research of the unique properties of MSCs have opened up new horizons for tissue regenerative therapies. However, certain drawbacks of the application of MSCs, such as the low survival rate of transplanted MSCs, unsatisfactory efficiency and even failure to regenerate under an unbalanced microenvironment, are concerning with regards to their wider therapeutic applications. The activity of stem cells is mainly regulated by the anatomical niche; where they are placed during their clinical and therapeutic applications. Crosstalk between various niche signals maintains MSCs in homeostasis, in which the WNT signaling pathway plays vital roles. Several external or internal stimuli have been reported to interrupt the normal bioactivity of stem cells. The irreversible tissue loss that occurs during infection at the site of tissue grafting suggests an inhibitory effect mediated by microbial infections within MSC niches. In addition, MSC­seeded tissue engineering success is difficult in various tissues, when sites of injury are under the effects of a severe infection despite the immunomodulatory properties of MSCs. In the present review, the current understanding of the way in which WNT signaling regulates MSC activity modification under physiological and pathological conditions was summarized. An effort was also made to illustrate parts of the underlying mechanism, including the inflammatory factors and their interactions with the regulatory WNT signaling pathway, aiming to promote the clinical translation of MSC­based therapy.

Influence Mechanism of Surfactants on Wettability of Coal with Different Metamorphic Degrees Based on Infrared Spectrum Experiments.

Based on experiments, a numerical analysis is used to quantitatively explore the influence of coal and surfactant microstructures on wettability. First, based on an infrared spectrum experiment, the distribution of oxygen-containing functional groups, aromatic hydrocarbons, and aliphatic hydrocarbons of coal and surfactants was obtained. Second, the wettability relationship between coal and different surfactants was determined by optical titration, and the coal dust wettability and surfaces were optimized. The key factors of the active agent wetting ability affecting lignite wetting mainly depend on the carbonyl, ether, and carboxyl groups in the surfactant. The factors affecting non-stick coal and gas coal wetting mainly depend on the ether group and aromatic amine in the surfactant. The factors affecting fat coal wetting mainly depend on the ether group and hydroxyl group in the surfactant. Finally, the factors affecting coking coal and anthracite wetting mainly depend on the surfactant ether group, aliphatic amine, and aromatic amine. Then, combining the structural parameters with the coal wetting results, the quantitative mathematical relationship between coal dust wettability, the important influencing factors of the surfactant, and the wettability index was established. Finally, a perfect and reasonable wettability evaluation model between coal and the surfactants was established. The relative activity of methyl ether and aromatic ether is greater than that of methyl ether, and the influence on the lignite, coking coal, and anthracite wettability conforms to the model . The influence on the non-caking coal and fat coal wettability conforms to the model , while the influence on the gas coal wettability conforms to the model Z = A + B 1 X 1 + B 2 X 2. In general, this study provides scientific guidance for the compounding of high-efficiency and environmentally protective composite dust suppressors to realize clean mine production.