Exploring the diversity of dissolved organic matter (DOM) properties and sources in different functional areas of a typical macrophyte - derived lake combined with optical spectroscopy and FT-ICR MS analysis.

Lake Baiyangdian is one of China's largest macrophyte - derived lakes, facing severe challenges related to water quality maintenance and eutrophication prevention. Dissolved organic matter (DOM) was a huge carbon pool and its abundance, property, and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems. In this study, Lake Baiyangdian was divided into four distinct areas: Unartificial Area (UA), Village Area (VA), Tourism Area (TA), and Breeding Area (BA). We examined the diversity of DOM properties and sources across these functional areas. Our findings reveal that DOM in this lake is predominantly composed of protein - like substances, as determined by excitation - emission matrix and parallel factor analysis (EEM - PARAFAC). Notably, the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA. Ultrahigh - resolution mass spectrometry (FT - ICR MS) unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds, suggesting that macrophytes significantly influence the material structure of DOM. DOM properties exhibited specific associations with water quality indicators in various functional areas, as indicated by the Mantel test. The connections between DOM properties and NO3N and NH3N were more pronounced in VA and BA than in UA and TA. Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.

Selective production of high-value fuel via catalytic upgrading of bio-oil over nitrogen-doped carbon-alumina hybrid supported cobalt catalysts.

Bio-oil derived from biomass fast pyrolysis can be upgraded to gasoline and diesel alternatives by catalytic hydrodeoxygenation (HDO). Here, the novel nitrogen-doped carbon-alumina hybrid supported cobalt (Co/NCAn, n = 1, 2.5, 5) catalyst is established by a coagulation bath technique. The optimized Co/NCA2.5 catalyst presented 100 % conversion of guaiacol, high selectivity to cyclohexane (93.6 %), and extremely high deoxygenation degree (97.3 %), respectively. Therein, the formation of cyclohexanol was facilitated by stronger binding energy and greater charge transfer between Co and NC which was unraveled by density functional theory calculations. In addition, the appropriate amount of Lewis acid sites enhanced the cleavage of the C-O bond in cyclohexanol, finally resulting in a remarkable selectivity for cyclohexane. Finally, the Co/NCA2.5 catalyst also exhibited excellent selectivity (93.1 %) for high heating value hydrocarbon fuel in crude bio-oil HDO. This work provides a theoretical basis on N dopants collaborating alumina hybrid catalysts for efficient HDO reaction.

Enriched environment treatment promotes neurofunctional recovery by regulating the ALK5/Smad2/3/Gadd45ß signaling pathway in rats with cerebral ischemia /reperfusion injury.

It has been demonstrated that an enriched environment (EE) treatment can alter neuroplasticity in neurodegenerative diseases. However, the role of EE treatment in ischemic stroke remains unclear. Previous findings have revealed that EE treatment can promote cerebral activin-receptor-like-kinase-5 (ALK5) expression after cerebral ischemia/reperfusion (I/R) injury. ALK5 has been identified as a potential mediator of neuroplasticity through its modulation of Smad2/3 and Gadd45ß. Therefore, the aim of this study was to investigate whether EE treatment could promote neurofunctional recovery by regulating the ALK5/Smad2/3/Gadd45ß pathway. The study utilized the rat model of middle cerebral artery occlusion/reperfusion (MCAO/R). The ALK5/Smad2/3/Gadd45ß signaling pathway changes were evaluated using western blotting (WB). Brain injury was assessed by infarct volume and neurobehavioral scores. The effect of EE treatment on neurogenesis was evaluated using Doublecortin (DCX) and Nestin, axonal plasticity with biotinylated dextran amine (BDA) nerve tracing, and dendritic plasticity was assessed using Golgi-Cox staining. EE treatment has been demonstrated to modulate the Smad2/3/Gadd45ß pathway by regulating the expression of ALK5. The protective effects of EE treatment on brain infarct volume, neurological function, newborn neurons, dendritic and axonal plasticity following cerebral I/R injury were counteracted by ALK5 silencing. EE treatment can enhance neurofunctional recovery after cerebral I/R injury, which is achieved by regulating the ALK5/Smad2/3/Gadd45ß signaling pathway to promote neuroplasticity.

Application and Method of Surface Plasmon Resonance Technology in the Preparation and Characterization of Biomedical Nanoparticle Materials.

Surface Plasmon Resonance (SPR) technology, as a powerful analytical tool, plays a crucial role in the preparation, performance evaluation, and biomedical applications of nanoparticles due to its real-time, label-free, and highly sensitive detection capabilities. In the nanoparticle preparation process, SPR technology can monitor synthesis reactions and surface modifications in real-time, optimizing preparation techniques and conditions. SPR enables precise measurement of interactions between nanoparticles and biomolecules, including binding affinities and kinetic parameters, thereby assessing nanoparticle performance. In biomedical applications, SPR technology is extensively used in the study of drug delivery systems, biomarker detection for disease diagnosis, and nanoparticle-biomolecule interactions. This paper reviews the latest advancements in SPR technology for nanoparticle preparation, performance evaluation, and biomedical applications, discussing its advantages and challenges in biomedical applications, and forecasting future development directions.

Mechanistic Insights into the Direct Deoxygenation of Phenolic Compounds over Novel Heusler Alloy Catalysts.

The catalytic deoxygenation of phenolic compounds is a crucial step in the valorization of biomass resources, which can effectively enhance the heating value and stability of primary biofuel. In this study, the catalytic mechanism of four Heusler alloy catalysts for the direct deoxidation pathway of phenol was studied through electronic structure regulation by element occupation. We found that Heusler alloys catalysts exhibit excellent catalytic activity in the dissociation activation of H2 and the cleavage of aryl hydroxyl bond (CAr-OH) bonds. The energy barriers for the direct cleavage of the CAr-OH bond in phenol on Ni2MoAl, Co2MoAl, Ni2NbAl and Ni2MoGa catalysts are 0.86, 0.95, 1.09, and 1.28 eV, respectively. And Y element of the X2YZ catalyst has a significant impact on this reaction, while the X element has a complex influence on the hydrogenation step of the unsaturated benzene ring. Microkinetic analysis further substantiates that the phenol (CAr-OH) bond cleavage step in the reaction exhibits a fast reaction rate and high extent of reaction. The reaction of hydroxyl hydrogenation to produce water exhibits the highest energy barrier, serving as the rate-determining step of the entire reaction. This issue could potentially be addressed by further fine-tuning the electronic structure.

A Convenient In Situ Preparation of Cu2ZnSnS4-Anatase Hybrid Nanocomposite for Photocatalysis/Photoelectrochemical Water-Splitting Hydrogen Production.

This study details the rational design and synthesis of Cu2ZnSnS4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS-A heterojunctions. As the concentration of titanium dioxide (TiO2) varied, the morphology of CZTS shifted from floral patterns to sheet-like structures. The resulting CZTS-A heterostructures underwent comprehensive characterization through photoelectrochemical response assessments, optical measurements, and electrochemical impedance spectroscopy analyses. Detailed photoelectrochemical (PEC) investigations demonstrated notable enhancements in photocurrent density and incident photon-to-electron conversion efficiency (IPCE). Compared to pure anatase electrodes, the optimized CZTS-A heterostructures exhibited a seven-fold increase in photocurrent density and reached a hydrogen production efficiency of 1.1%. Additionally, the maximum H2 production rate from these heterostructures was 11-times greater than that of pure anatase and 250-times higher than the original CZTS after 2 h of irradiation. These results underscore the enhanced PEC performance of CZTS-A heterostructures, highlighting their potential as highly efficient materials for solar water splitting. Integrating Cu2ZnSnS4 nanoparticles (NPs) within TiO2 (anatase) heterostructures implied new avenues for developing earth-abundant and cost-effective photocatalytic systems for renewable energy applications.

Shared genetic basis connects smoking behaviors and bone health: Insights from a genome-wide cross-trait analysis.

Although the negative association of tobacco smoking with osteoporosis is well-documented, little is known regarding the shared genetic basis underlying these conditions. In this study, we aim to investigate a shared genetic architecture between smoking and heel estimated bone mineral density (eBMD), a reliable proxy for osteoporosis. We conducted a comprehensive genome-wide cross-trait analysis to identify genetic correlation, pleiotropic loci and causal relationship of smoking with eBMD, leveraging summary statistics of the hitherto largest genome-wide association studies conducted in European ancestry for smoking initiation (Nsmoker = 1 175 108, Nnonsmoker = 1 493 921), heaviness (cigarettes per day, N = 618 489), cessation (Ncurrent smoker = 304 244, Nformer smoker = 843 028), and eBMD (N = 426 824). A significant negative global genetic correlation was found for smoking cessation and eBMD (${r}_g$ = -0.051, P = 0.01), while we failed to identify a significant global genetic correlation of smoking initiation or heaviness with eBMD. Partitioning the whole genome into independent blocks, we observed six significant shared local signals for smoking and eBMD, with 22q13.1 showing the strongest regional genetic correlation. Such a genetic overlap was further supported by 71 pleiotropic loci identified in the cross-trait meta-analysis. Mendelian randomization identified no causal effect of smoking initiation (beta = -0.003 g/cm2, 95%CI = -0.033-0.027) or heaviness (beta = -0.017 g/cm2, 95%CI = -0.072-0.038) on eBMD, but a putative causal effect of genetic predisposition to being a current smoker was associated with a lower eBMD compared to former smokers (beta = -0.100 g/cm2, 95%CI = -0.181- - 0.018). Our study demonstrates a pronounced biological pleiotropy as well as a putative causal link between current smoking status and eBMD, providing novel insights into the primary prevention and modifiable intervention of osteoporosis by advocating individuals to avoid, reduce or quit smoking as early as possible.

We conducted a comprehensive genome-wide cross-trait analysis to investigate the shared genetic basis and causal relationship underlying smoking and osteoporosis. Our findings revealed that smoking and eBMD are inherently linked through biological pleiotropy. Importantly, our study discovered that quitting smoking significantly reduced the risk of lower eBMD. We recommend individuals to avoid, reduce, or quit smoking as early as possible to protect bone health.

TUFM in health and disease: exploring its multifaceted roles.

The nuclear-encoded mitochondrial protein Tu translation elongation factor, mitochondrial (TUFM) is well-known for its role in mitochondrial protein translation. Originally discovered in yeast, TUFM demonstrates significant evolutionary conservation from prokaryotes to eukaryotes. Dysregulation of TUFM has been associated with mitochondrial disorders. Although early hypothesis suggests that TUFM is localized within mitochondria, recent studies identify its presence in the cytoplasm, with this subcellular distribution being linked to distinct functions of TUFM. Significantly, in addition to its established function in mitochondrial protein quality control, recent research indicates a broader involvement of TUFM in the regulation of programmed cell death processes (e.g., autophagy, apoptosis, necroptosis, and pyroptosis) and its diverse roles in viral infection, cancer, and other disease conditions. This review seeks to offer a current summary of TUFM's biological functions and its complex regulatory mechanisms in human health and disease. Insight into these intricate pathways controlled by TUFM may lead to the potential development of targeted therapies for a range of human diseases.

Regional differences in lead (Pb) and tetracycline (TC) binding behavior of sediment dissolved organic matter (SDOM): Effects of DOM heterogeneity and microbial degradation.

Lake Nansi, primarily dominated by macrophytes, faces threats from heavy metals and antibiotics due to human activity. This study investigated sediment dissolved organic matter (SDOM) characteristics and complexation of lead (Pb) and tetracycline (TC) in barren zone (BZ) and submerged macrophytes zone (PZ). Additionally, a microbial degradation experiment was conducted to examine its impact on the regional variations in complexation. SDOM abundance and protein-like materials in PZ was significantly greater than in BZ, indicating a probable contribution from the metabolism and decomposition of submerged macrophytes. Both zones exhibited a higher affinity of SDOM for Pb compared to TC, with all four components participating in Pb complexation. Protein-like materials in PZ had a higher binding ability (LogKPb=4.19 ± 1.07, LogKTC=3.89 ± 0.67) than in BZ (LogKPb=3.98 ± 0.61, LogKTC=3.69 ± 0.13), suggesting a potential presence of organically bound Pb and TC due to the higher abundance of protein-like materials in PZ. Although microbial communities differed noticeably, the degradation patterns of SDOM were similar in both zones, affecting the binding ability of SDOM in each. Notably, the fulvic-like component C4 emerged as the dominant binding material for both Pb and TC in both zones. Degradation might increase the amount of organically bound TC due to the increase in the LogKTC.

12-O-deacetyl-phomoxanthone A inhibits ovarian tumor growth and metastasis by downregulating PDK4.

AIMS: The xanthone dimer 12-O-deacetyl-phomoxanthone A (12-ODPXA) was extracted from the secondary metabolites of the endophytic fungus Diaporthe goulteri. The 12-ODPXA compound exhibited anticancer properties in murine lymphoma; however, the anti-ovarian cancer (OC) mechanism has not yet been explored. Therefore, the present study evaluated whether 12-ODPXA reduces OC cell proliferation, metastasis, and invasion by downregulating pyruvate dehydrogenase kinase (PDK)4 expression. METHODS: Cell counting kit-8, colony formation, flow cytometry, wound healing, and transwell assays were performed to examine the effects of 12-ODPXA on OC cell proliferation, apoptosis, migration, and invasion. Transcriptome analysis was used to predict the changes in gene expression. Protein expression was determined using western blotting. Glucose, lactate, and adenosine triphosphate (ATP) test kits were used to measure glucose consumption and lactate and ATP production, respectively. Zebrafish xenograft models were constructed to elucidate the anti-OC effects of 12-ODPXA. RESULTS: The 12-ODPXA compound inhibited OC cell proliferation, migration, invasion, and glycolysis while inducing cell apoptosis via downregulation of PDK4. In vivo experiments showed that 12-ODPXA suppressed tumor growth and migration in zebrafish. CONCLUSION: Our data demonstrate that 12-ODPXA inhibits ovarian tumor growth and metastasis by downregulating PDK4, revealing the underlying mechanisms of action of 12-ODPXA in OC.

Targeting furin, a cellular proprotein convertase, for COVID-19 prevention and therapeutics.

SARS-CoV-2 has triggered an international outbreak of the highly contagious acute respiratory disease known as COVID-19. Identifying key targets in the virus infection lifecycle is crucial for developing effective prevention and therapeutic strategies against it. Furin is a serine endoprotease that belongs to the family of proprotein convertases and plays a critical role in the entry of host cells by SARS-CoV-2. Furin can cleave a specific S1/S2 site, PRRAR, on the spike protein of SARS-CoV-2, which promotes viral transmission by facilitating membrane fusion. Hence, targeting furin could hold clinical implications for the prevention and treatment of COVID-19. This review offers an overview of furin's structure, substrates, function, and inhibitors, with a focus on its potential role in SARS-CoV-2 infection.

Effects of weight loss on QTc in people with obesity: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Overweight and obesity have been found to exhibit a statistically significant increase in corrected QT interval (QTc), a major contributing factor to sudden death. However, the influence of widely used weight loss strategies including diet, exercise, anti-obesity drugs, and bariatric surgery on QTc remains inconsistent. Therefore, the present systematic review and meta-analysis aim to quantitatively analyse and evaluate the effect of weight loss on QTc in obese patients after diet control with exercise intervention and anti-obesity drugs, as well as bariatric surgery. METHODS: Twenty randomised controlled trials (RCT) and observational studies were included in the meta-analysis on the effects of weight loss on QTc. The fixed-effects model was employed in the RCTs, and the random-effects model was employed due to the presence of statistical heterogeneity among observational studies. Subgroup analysis was conducted to understand the differences in distinct weight loss methods and follow-up time. RESULTS: Overall, the QTc of people with obesity after weight loss was shorter than that before (mean difference (MD) = 21.97 ms, 95% confidence interval (CI) = 12.42, 31.52, p < .0001). Subgroup analysis restricted to seven included studies whose intervention was diet control with exercise showed a decrease of QTc with statistical significance (MD = 9.35 ms, 95%CI = 2.56, 37.54, p = .007). In the remaining 11 studies, bariatric surgery was the weight loss method. The results also showed a shortening of QTc after surgery, and the difference was statistically significant (MD = 29.04 ms, 95%CI = -16.46, 41.62, p < .00001). A statistically significant difference in QTc shortening at 6 months compared to pre-operation values was further observed (MD = -31.01 ms, 95%CI = -2.89, -59.12, p = .03). The shortening of QTc at 12 months of follow-up was also significantly different from that before surgery (MD = 36.47 ms, 95%CI = 14.17, 58.78, p < .00001). Moreover, the differences became more pronounced as the follow-up time extended. CONCLUSIONS: We demonstrate that weight loss links to a shortened QTc, without considering the means of weight loss. Bariatric surgery has been found to result in a greater reduction in QTc.

Linc00511 Promotes Thyroid Cancer Through the miR-4739/RNF38 Pathway.

Objective: To analyze the effect of Linc00511 on thyroid cancer through the miR-4739/RNF38 pathway. Methods: A total of 78 patients in our hospital from July 2020 to July 2021 were collected, which were diagnosed with thyroid cancer after clinicopathological examination. Their cancer tissue samples were included in the thyroid cancer tissue group, and the fat 2 cm tissue samples were included in the para-cancer tissue group. Real-time quantitative PCR was used to detect the expression of Linc00511, miR-4739 and RNF38 in tissue samples from the two groups. Statistical analysis of data was performed using SPSS26.0. The correlation between Linc00511, miR-4739 and RNF38 were analyzed by Pearson's correlation coefficient. The expression of Linc00511 in thyroid cancer tissues with different clinicopathological characteristics were compared. Results: The expression levels of Linc00511 and RNF38 in thyroid cancer group were significantly higher than paracancer group, while miR-4739 levels were significantly lower (P < .05). Pearson correlation coefficient analysis showed that there was significant negative correlation between Linc00511 and miR-4739 expression and significant positive correlation between Linc00511 and RNF38 expression (P < .05). There was no significant difference in the expression of Linc00511 among different ages, sexes, and cancer types (P > .05). The expression of Linc00511 in patients with TNM stages I, II, and III were increased with the increase of TNM stage (P < .05). The expression of Linc00511 in patients with tumor diameter ≥1 cm was higher than that in patients with tumor diameter <1 cm and the difference was statistically significant (P < .05). Conclusion: Linc00511 and RNF38 were significantly overexpressed in thyroid cancer tissues, while miR-4739 was significantly underexpressed. In thyroid cancer, Linc00511 can promote the invasion and metastasis of thyroid cancer cells by targeting miR-4739 and RNF38, and its expression level may reflect the progression of thyroid cancer, which can provide target reference for the clinical treatment of thyroid cancer.

A comprehensive genome-wide cross-trait analysis of sexual factors and uterine leiomyoma.

Age at first sexual intercourse (AFS) and lifetime number of sexual partners (NSP) may influence the pathogenesis of uterine leiomyoma (UL) through their associations with hormonal concentrations and uterine infections. Leveraging summary statistics from large-scale genome-wide association studies conducted in European ancestry for each trait (NAFS = 214,547; NNSP = 370,711; NUL = 302,979), we observed a significant negative genomic correlation for UL with AFS (rg = -0.11, P = 7.83×10-4), but not with NSP (rg = 0.01, P = 0.62). Four specific genomic regions were identified as contributing significant local genetic correlations to AFS and UL, including one genomic region further identified for NSP and UL. Partitioning SNP-heritability with cell-type-specific annotations, a close clustering of UL with both AFS and NSP was identified in immune and blood-related components. Cross-trait meta-analysis revealed 15 loci shared between AFS/NSP and UL, including 7 novel SNPs. Univariable two-sample Mendelian randomization (MR) analysis suggested no evidence for a causal association between genetically predicted AFS/NSP and risk of UL, nor vice versa. Multivariable MR adjusting for age at menarche or/and age at natural menopause revealed a significant causal effect of genetically predicted higher AFS on a lower risk of UL. Such effect attenuated to null when age at first birth was further included. Utilizing participant-level data from the UK Biobank, one-sample MR based on genetic risk scores yielded consistent null findings among both pre-menopausal and post-menopausal females. From a genetic perspective, our study demonstrates an intrinsic link underlying sexual factors (AFS and NSP) and UL, highlighting shared biological mechanisms rather than direct causal effects. Future studies are needed to elucidate the specific mechanisms involved in the shared genetic influences and their potential impact on UL development.

Phosphorus release and distribution in sediment resuspension systems under disturbing conditions.

The resuspension of phosphorus (P) in sediments has the most significant contribution to the overlying water. The PP release characterization during resuspension was investigated. The results indicated that the P in suspensions had more release risk compared to the sediments. The particulate P (PP) concentration (0.54 mg L-1) under high-intensity rotational speed (250 rad min-1) was about five times higher than others (0.11 mg L-1). The sorption parameters of zero equilibrium P concentration (EPC0F) and soluble reactive P (SRP) were significantly correlated with each other (p < 0.01, r = 0.73). Suspended solids expressed stronger P source than sediments. The values of EPC0F was highly significantly correlated with the sorption coefficient (KF) and native adsorbed P (NAP) (p < 0.01). The mean values of NAP were 0.0612 mg g-1 and 0.0604 mg g-1 in the Prophase and Metaphase, respectively, and 0.0586 mg g-1 at Anaphase. The values of P sorption index (PSI) ranged from 0.4359 to 0.6862 L g-1, with mean values of 0.5350 L g-1 (Prophase), 0.6061 L g-1 (Metaphase), and 0.4967 L g-1 (Anaphase). The degree of P saturation (DPS) decreased in the order of Anaphase (2.73%) > Prophase (2.53%) > Metaphase (2.12%). The release risk index of P (ERI) decreased in the order of Anaphase (5.47%) > Prophase (4.72%) > Metaphase (3.59%), with a range of 2.12%-8.56%. To fast and slow scale, the results of NaOH-P (V1<0, V2>0) contribution indicated that the persistent disturbance promoted the release of adsorbed dissolved PP from NaOH-P in suspended sediment to the overlying water. The contribution of HCl-P (V2 > 0) was positive in the Anaphase of the slow scale, and HCl-P was a PP source in the frequently disturbing conditions.

Association between quality of discharge teaching and self-management in patients after percutaneous coronary intervention: A chain mediation model.

AIMS: To examine chain mediating effect of discharge readiness and self-efficacy between quality of discharge teaching and self-management in patients after percutaneous coronary intervention (PCI). BACKGROUND: Although self-management after PCI has significant benefits in controlling risk factors and delaying disease progression, the status of self-management remains unoptimistic. A large number of studies have explored the close relationship between the quality of discharge teaching and patients self-management, but little is known about the underlying mechanisms. METHODS: The cross-sectional samples was collected from a tertiary hospital in China. Self-reported questionnaires were used to assess quality of discharge teaching, discharge readiness, self-efficacy and self-management. Pearson correlation analysis and mediation effect analysis were used for statistical analysis. REPORTING METHOD: The study used the STROBE checklist for reporting. RESULTS: A total of 198 patients with a mean age of 64.99 ± 11.32 (34-85) were included. The mean score of self-management was 88.41 ± 11.82. Quality of discharge teaching, discharge readiness, self-efficacy and self-management were all positively correlated. Mediation effect analysis showed that the mediating effects of discharge readiness, self-efficacy, discharge readiness and self-efficacy between quality of discharge teaching and self-management were 0.157, 0.177 and 0.049, respectively, accounting for 21.96%, 24.76% and 6.85% of the total effect. CONCLUSION: The quality of discharge teaching for patients after PCI not only directly affects self-management, but also can indirectly affect self-management through discharge readiness and self-efficacy. RELEVANCE TO CLINICAL PRACTICE: To improve the life quality of patients after PCI, medical staff should pay attention to the influence of self-management of quality of discharge teaching, and develop intervention strategies based on the path of discharge readiness and self-efficacy. PATIENT OR PUBLIC CONTRIBUTION: Questionnaires filled out by patients were used to understand the association between quality of discharge teaching, discharge readiness, self-efficacy and self-management.

Experimental study on the deterioration of mechanical properties of sandy mudstone under different water-gas interactions.

Based on the water-rock-gas coupling test system, the work combined the scanning electron microscope and XTDIC 3D full-field strain measurement system. The Brazilian splitting test was performed on four groups of sandy mudstone specimens under contrast (CO), mash-gas soaking (MS), water-mash gas soaking (WM), and water-soaking (WS) conditions. The tensile strength, deformation failure, and microscopic characteristics of fractures were studied to reveal the deterioration mechanism of the tensile properties of sandy mudstone under water-gas coupling. The results showed that the uniaxial tensile strength of sandy mudstone specimens under the three soaking conditions was less than that of the contrast conditions. Compared with specimens in the CO group, the tensile strength of specimens in MS-WS groups was reduced; the WS group decreased the most. Specimens changed from brittle failure to plastic failure after soaking. The decrease rate in strength after the peak was consistent with the change trend in tensile strength. It led to a larger localized deformation zone of specimens and more obvious displacement. The deformation localization zone of the WS group was the broadest, with the most intense displacement. Besides, stress concentration first occurred in the submerged part of the WM group. Fractures expanded in the direction of maximum principal strain. The internal pore structure of sandy mudstone specimens in each group changed after soaking. The average porosity, maximum pore area, and probability entropy of specimens in WS-MS groups increased compared to the CO group. The WS group had the largest reduction and the MS group had the smallest. The pre-peak energy storage capacity of sandy mudstone specimens was gradually weakened. Compared with the CO group, that in the WS-MS groups was reduced. The WS group had the greatest reduction, and the MS group had the smallest. The deterioration effect of water on the interior of sandy mudstone was stronger than that of gas. The work is of great significance for understanding the stability of coal and rocks in closed-pit high-gas mines.

Antibiotic-loaded bone cement fixation technique combined with bilateral pectoralis major muscle flaps tension-free management for sternal infection after midline sternotomy.

INTRODUCTION: Deep sternal wound infection (DSWI) after midline sternotomy of cardiac surgery is a challenging complication that affects the outcome of surgery. This study aims to assess the clinical effectiveness of the antibiotic-loaded bone cement fixation technique combined with bilateral pectoralis major muscle flaps tension-free management in the treatment of DSWI. METHODS: We retrospectively analyzed 5 patients with DSWI who underwent antibiotic-loaded bone cement combined with bilateral pectoralis major muscle flaps for chest wall reconstruction after sternotomy for cardiac surgery in a tertiary hospital in China from January 2020 to December 2021. The clinical and follow-up data were retrospectively analyzed. RESULTS: All patients had no perioperative mortalities, no postoperative complications, 100% wound healing, and an average hospital stay length of 24 days. The follow-up periods were from 6 to 35 months (mean 19.6 months). None of the cases showed wound problems after initial reconstruction using antibiotic-loaded bone cement combined with bilateral pectoralis major muscle flaps. CONCLUSIONS: We report our successful treatment of DSWI, using antibiotic-loaded bone cement fixation technique combined with bilateral pectoralis major muscle flaps tension-free management. The clinical and follow-up results are favorable.