Measuring and modeling the dynamics of mitotic error correction.

Error correction is central to many biological systems and is critical for protein function and cell health. During mitosis, error correction is required for the faithful inheritance of genetic material. When functioning properly, the mitotic spindle segregates an equal number of chromosomes to daughter cells with high fidelity. Over the course of spindle assembly, many initially erroneous attachments between kinetochores and microtubules are fixed through the process of error correction. Despite the importance of chromosome segregation errors in cancer and other diseases, there is a lack of methods to characterize the dynamics of error correction and how it can go wrong. Here, we present an experimental method and analysis framework to quantify chromosome segregation error correction in human tissue culture cells with live cell confocal imaging, timed premature anaphase, and automated counting of kinetochores after cell division. We find that errors decrease exponentially over time during spindle assembly. A coarse-grained model, in which errors are corrected in a chromosome-autonomous manner at a constant rate, can quantitatively explain both the measured error correction dynamics and the distribution of anaphase onset times. We further validated our model using perturbations that destabilized microtubules and changed the initial configuration of chromosomal attachments. Taken together, this work provides a quantitative framework for understanding the dynamics of mitotic error correction.

Chronic viral infection impairs immune memory to a different pathogen.

Chronic viral infections cause T cell dysfunction in both animal models and human clinical settings, thereby affecting the ability of the host immune system to clear viral pathogens and develop proper virus-specific immune memory. However, the impact of chronic viral infections on the host's immune memory to other pathogens has not been well described. In this study, we immunized mice with recombinant Listeria monocytogenes expressing OVA (Lm-OVA) to generate immunity to Lm and allow analysis of OVA-specific memory T (Tm) cells. We then infected these mice with lymphocytic choriomeningitis virus (LCMV) strain Cl-13 which establishes a chronic infection. We found that chronically infected mice were unable to protect against Listeria re-challenge. OVA-specific Tm cells showed a progressive loss in total numbers and in their ability to produce effector cytokines in the context of chronic LCMV infection. Unlike virus-specific T cells, OVA-specific Tm cells from chronically infected mice did not up-regulate the expression of inhibitory receptors, a hallmark feature of exhaustion in virus-specific T cells. Finally, OVA-specific Tm cells failed to mount a robust recall response after bacteria re-challenge both in the chronically infected and adoptively transferred naïve hosts. These results show that previously established bacteria-specific Tm cells become functionally impaired in the setting of an unrelated bystander chronic viral infection, which may contribute to poor immunity against other pathogens in the host with chronic viral infection.

Switching of brain networks across different cerebral perfusion states: insights from EEG dynamic microstate analyses.

The alteration of neural interactions across different cerebral perfusion states remains unclear. This study aimed to fulfill this gap by examining the longitudinal brain dynamic information interactions before and after cerebral reperfusion. Electroencephalogram in eyes-closed state at baseline and postoperative 7-d and 3-month follow-ups (moyamoya disease: 20, health controls: 23) were recorded. Dynamic network analyses were focused on the features and networks of electroencephalogram microstates across different microstates and perfusion states. Considering the microstate features, the parameters were disturbed of microstate B, C, and D but preserved of microstate A. The transition probabilities of microstates A-B and B-D were increased to play a complementary role across different perfusion states. Moreover, the microstate variability was decreased, but was significantly improved after cerebral reperfusion. Regarding microstate networks, the functional connectivity strengths were declined, mainly within frontal, parietal, and occipital lobes and between parietal and occipital lobes in different perfusion states, but were ameliorated after cerebral reperfusion. This study elucidates how dynamic interaction patterns of brain neurons change after cerebral reperfusion, which allows for the observation of brain network transitions across various perfusion states in a live clinical setting through direct intervention.

Generation of B7-H3 isoform regulated by ANXA2/NSUN2/YBX1 axis in human glioma.

In recent years, in the development of emerging immunotherapy, B7-H3 is also termed as CD276 and has become a novel chimeric antigen receptor (CAR)-T target against glioma and other tumours, and aroused extensive attention. However, B7-H3 has three isoforms (2, 3 and 4Ig) with the controversial expression and elusive function in tumour especially glioma. The current study mainly focuses on the regulatory factors and related mechanisms of generation of different B7-H3 isoforms. First, we have determined that 2Ig is dominant in glioma with high malignancy, and 4Ig is widely expressed, whereas 3Ig shows negative expression in all glioma. Next, we have further found that RNA binding protein annexin A2 (ANXA2) is essential for B7-H3 isoform maintenance, but fail to determine the choice of 4Ig or 2Ig. RNA methyltransferase NOP2/Sun RNA methyltransferase 2 (NSUN2) and 5-methylcytosine reader Y-box binding protein 1 (YBX1) facilitate the production of 2Ig. Our findings have uncovered a series of factors (ANXA2/NSUN2/YBX1) that can determine the alternative generation of different isoforms of B7-H3 in glioma. Our result aims to help peers gain a clearer understanding of the expression and regulatory mechanisms of B7H3 in tumour patients, and to provide better strategies for designing B7H3 as a target in immunotherapy.

CMTM 6 promotes the development of thyroid cancer by inhibiting NIS activity through activating the MAPK signaling pathway.

Thyroid cancer is the most common type of endocrine cancer. Chemokine-like factor (CKLF)-like MARVEL transmembrane domain containing 6 (CMTM6) is recognized as one of its potential immunotherapy targets. The purpose of this study was to investigate the role and molecular mechanism of CMTM6 in regulating the development of thyroid cancer cells. In this study, expression levels of CMTM6 and the sodium/iodide symporter (NIS) were detected by qRT-PCR. Additionally, colony formation assay and flow cytometry were used to detect cell proliferation and apoptosis, while expression levels of various proteins were assessed using Western blotting. Further, the apoptosis and invasion capacity of cells were investigated by scratch and transwell experiments. Finally, the effect of CMTM6 on the epithelial-mesenchymal transition (EMT) of thyroid cancer cells was determined by immunofluorescence assay, which measured the expression levels of epithelial and mesenchymal phenotypic markers. The results of qRT-PCR experiments showed that CMTM6 was highly expressed in thyroid cancer tissues and cells. In addition, knockdown of CMTM6 expression significantly increased NIS expression. Function experiments demonstrated that small interfering (si)-CMTM6 treatment inhibited the proliferation, migration, invasion, and EMT of thyroid cancer cells, while promoting apoptosis of FTC133 cells. Furthermore, mechanistic studies showed that mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) phosphorylation were inhibited by si-CMTM6, as demonstrated by Western blot experiments. In conclusion, our findings demonstrated the role of CMTM6 in the metastasis of thyroid cancer. Briefly, CMTM6 exerts its tumor-promoting effect through the MAPK signaling pathway and could potentially be used as a valuable biomarker for thyroid cancer diagnosis and prognosis.

NHH promotes Sepsis-associated Encephalopathy with the expression of AQP4 in astrocytes through the gut-brain Axis.

Sepsis-associated encephalopathy (SAE) is a significant cause of mortality in patients with sepsis. Despite extensive research, its exact cause remains unclear. Our previous research indicated a relationship between non-hepatic hyperammonemia (NHH) and SAE. This study aimed to investigate the relationship between NHH and SAE and the potential mechanisms causing cognitive impairment. In the in vivo experimental results, there were no significant abnormalities in the livers of mice with moderate cecal ligation and perforation (CLP); however, ammonia levels were elevated in the hippocampal tissue and serum. The ELISA study suggest that fecal microbiota transplantation in CLP mice can reduce ammonia levels. Reduction in ammonia levels improved cognitive dysfunction and neurological impairment in CLP mice through behavioral, neuroimaging, and molecular biology studies. Further studies have shown that ammonia enters the brain to regulate the expression of aquaporins-4 (AQP4) in astrocytes, which may be the mechanism underlying brain dysfunction in CLP mice. The results of the in vitro experiments showed that ammonia up-regulated AQP4 expression in astrocytes, resulting in astrocyte damage. The results of this study suggest that ammonia up-regulates astrocyte AQP4 expression through the gut-brain axis, which may be a potential mechanism for the occurrence of SAE.

Bicyclol attenuates pulmonary fibrosis with silicosis via both canonical and non-canonical TGF-ß1 signaling pathways.

BACKGROUND: Silicosis is an irreversible fibrotic disease of the lung caused by chronic exposure to silica dust, which manifests as infiltration of inflammatory cells, excessive secretion of pro-inflammatory cytokines, and pulmonary diffuse fibrosis. As the disease progresses, lung function further deteriorates, leading to poorer quality of life of patients. Currently, few effective drugs are available for the treatment of silicosis. Bicyclol (BIC) is a compound widely employed to treat chronic viral hepatitis and drug-induced liver injury. While recent studies have demonstrated anti-fibrosis effects of BIC on multiple organs, including liver, lung, and kidney, its therapeutic benefit against silicosis remains unclear. In this study, we established a rat model of silicosis, with the aim of evaluating the potential therapeutic effects of BIC. METHODS: We constructed a silicotic rat model and administered BIC after injury. The FlexiVent instrument with a forced oscillation system was used to detect the pulmonary function of rats. HE and Masson staining were used to assess the effect of BIC on silica-induced rats. Macrophages-inflammatory model of RAW264.7 cells, fibroblast-myofibroblast transition (FMT) model of NIH-3T3 cells, and epithelial-mesenchymal transition (EMT) model of TC-1 cells were established in vitro. And the levels of inflammatory mediators and fibrosis-related proteins were evaluated in vivo and in vitro after BIC treatment by Western Blot analysis, RT-PCR, ELISA, and flow cytometry experiments. RESULTS: BIC significantly improved static compliance of lung and expiratory and inspiratory capacity of silica-induced rats. Moreover, BIC reduced number of inflammatory cells and cytokines as well as collagen deposition in lungs, leading to delayed fibrosis progression in the silicosis rat model. Further exploration of the underlying molecular mechanisms revealed that BIC suppressed the activation, polarization, and apoptosis of RAW264.7 macrophages induced by SiO2. Additionally, BIC inhibited SiO2-mediated secretion of the inflammatory cytokines IL-1ß, IL-6, TNF-α, and TGF-ß1 in macrophages. BIC inhibited FMT of NIH-3T3 as well as EMT of TC-1 in the in vitro silicosis model, resulting in reduced proliferation and migration capability of NIH-3T3 cells. Further investigation of the cytokines secreted by macrophages revealed suppression of both FMT and EMT by BIC through targeting of TGF-ß1. Notably, BIC blocked the activation of JAK2/STAT3 in NIH-3T3 cells required for FMT while preventing both phosphorylation and nuclear translocation of SMAD2/3 in TC-1 cells necessary for the EMT process. CONCLUSION: The collective data suggest that BIC prevents both FMT and EMT processes, in turn, reducing aberrant collagen deposition. Our findings demonstrate for the first time that BIC ameliorates inflammatory cytokine secretion, in particular, TGF-ß1, and consequently inhibits FMT and EMT via TGF-ß1 canonical and non-canonical pathways, ultimately resulting in reduction of aberrant collagen deposition and slower progression of silicosis, supporting its potential as a novel therapeutic agent.

Utilizing radiomics and dosiomics with AI for precision prediction of radiation dermatitis in breast cancer patients.

PURPOSE: This study explores integrating clinical features with radiomic and dosiomic characteristics into AI models to enhance the prediction accuracy of radiation dermatitis (RD) in breast cancer patients undergoing volumetric modulated arc therapy (VMAT). MATERIALS AND METHODS: This study involved a retrospective analysis of 120 breast cancer patients treated with VMAT at Kaohsiung Veterans General Hospital from 2018 to 2023. Patient data included CT images, radiation doses, Dose-Volume Histogram (DVH) data, and clinical information. Using a Treatment Planning System (TPS), we segmented CT images into Regions of Interest (ROIs) to extract radiomic and dosiomic features, focusing on intensity, shape, texture, and dose distribution characteristics. Features significantly associated with the development of RD were identified using ANOVA and LASSO regression (p-value < 0.05). These features were then employed to train and evaluate Logistic Regression (LR) and Random Forest (RF) models, using tenfold cross-validation to ensure robust assessment of model efficacy. RESULTS: In this study, 102 out of 120 VMAT-treated breast cancer patients were included in the detailed analysis. Thirty-two percent of these patients developed Grade 2+ RD. Age and BMI were identified as significant clinical predictors. Through feature selection, we narrowed down the vast pool of radiomic and dosiomic data to 689 features, distributed across 10 feature subsets for model construction. In the LR model, the J subset, comprising DVH, Radiomics, and Dosiomics features, demonstrated the highest predictive performance with an AUC of 0.82. The RF model showed that subset I, which includes clinical, radiomic, and dosiomic features, achieved the best predictive accuracy with an AUC of 0.83. These results emphasize that integrating radiomic and dosiomic features significantly enhances the prediction of Grade 2+ RD. CONCLUSION: Integrating clinical, radiomic, and dosiomic characteristics into AI models significantly improves the prediction of Grade 2+ RD risk in breast cancer patients post-VMAT. The RF model analysis demonstrates that a comprehensive feature set maximizes predictive efficacy, marking a promising step towards utilizing AI in radiation therapy risk assessment and enhancing patient care outcomes.

Cause-specific mortality in a population-level cohort of diffuse large B-cell lymphoma following chemotherapy in the early 21st century.

Diffuse large B-cell lymphoma (DLBCL) is a severe non-Hodgkin's lymphoma. Life expectancy has improved with rituximab, but cause-specific mortality data is lacking. Using the Surveillance, Epidemiology, and End Results (SEER) database to study 27,449 individuals aged 20-74 years diagnosed with primary DLBCL who received chemotherapy between 2000 and 2019, we calculated standardized mortality rate (SMR) and excess absolute risk (EAR) and examined the connection between age, sex, time after diagnosis, and cause of death. Based on 12,205 deaths, 68.7% were due to lymphoma, 20.1% non-cancer causes, and 11.2% other cancers. Non-cancer mortality rates (SMR 1.2; EAR, 21.5) increased with DLBCL compared to the general population. The leading non-cancer death causes were cardiovascular (EAR, 22.6; SMR, 1.6) and infectious (EAR, 9.0; SMR, 2.9) diseases with DLBCL. Risks for non-cancer death and solid neoplasms are highest within the first diagnosis year, then decrease. Among socioeconomic factors, being white, being married, and having a higher income were favorable factors for reducing non-cancer mortality. To improve survival, close surveillance, assessment of risk factors, and early intervention are needed.

Analysis of CCND3 mutations in diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL), accounts for 30-40% of newly diagnosed lymphomas, has an overall cure rate of approximately 60%. Despite previous reports suggesting a negative prognostic association between CCND3 mutations and Burkitt lymphoma, their prognostic implications in DLBCL remain controversial. To investigate this, we evaluated CCND3 mutation status in 2059 DLBCL patient samples from four database (integrated cohort) and additional 167 DLBCL patient samples in our center (JSPH cohort). The mutation was identified in 5.5% (113/2059) of the cases in the integrated cohort, with 86% (97/113) found in exon 5. Furthermore, P284, R271, I290 and Q276 are described as CCND3 mutation hotspots. CCND3 mutation was associated with decreased overall survival (OS) in the integrated cohort (P = 0.0407). Further subgroup analysis revealed that patients diagnosed as EZB subtype DLBCL by LymphGen algorithm with CCND3 mutations had poorer OS than patients diagnosed as EZB subtype without CCND3 mutations (P = 0.0140). Using the next-generation sequencing (NGS) in the JSPH cohort, it was found that both cell cycle and DNA replication pathways were highly upregulated in patients with CCND3 mutations. Our results suggest that CCND3 mutations can serve as a novel prognostic factor in DLBCL pathogenesis. Consequently, the development of personalized therapeutic strategies for DLBCL patients with CCND3 mutations might enhance their prognosis.

Identify truly high-risk TP53-mutated diffuse large B cell lymphoma patients and explore the underlying biological mechanisms.

TP53 mutation (TP53-mut) correlates with inferior survival in many cancers, whereas its prognostic role in diffuse large B-cell lymphoma (DLBCL) is still in controversy. Therefore, more precise risk stratification needs to be further explored for TP53-mut DLBCL patients. A set of 2637 DLBCL cases from multiple cohorts, was enrolled in our analysis. Among the 2637 DLBCL patients, 14.0% patients (370/2637) had TP53-mut. Since missense mutations account for the vast majority of TP53-mut DLBCL patients, and most non-missense mutations affect the function of the P53 protein, leading to worse survival rates, we distinguished patients with missense mutations. A TP53 missense mutation risk model was constructed based on a 150-combination machine learning computational framework, demonstrating excellent performance in predicting prognosis. Further analysis revealed that patients with high-risk missense mutations are significantly associated with early progression and exhibit dysregulation of multiple immune and metabolic pathways at the transcriptional level. Additionally, the high-risk group showed an absolutely suppressed immune microenvironment. To stratify the entire cohort of TP53-mut DLBCL, we combined clinical characteristics and ultimately constructed the TP53 Prognostic Index (TP53PI) model. In summary, we identified the truly high-risk TP53-mut DLBCL patients and explained this difference at the mutation and transcriptional levels.

CD31 orchestrates metabolic regulation in autophagy pathways of rheumatoid arthritis.

Synovitis is characterized by a distinct metabolic profile featuring the accumulation of lactate, a byproduct of cellular metabolism within inflamed joints. This study reveals that the activation of the CD31 signal by lactate instigates a metabolic shift, specifically initiating endothelial cell autophagy. This adaptive process plays a pivotal role in fulfilling the augmented energy and biomolecule demands associated with the formation of new blood vessels in the synovium of Rheumatoid Arthritis (RA). Additionally, the amino acid substitutions in the CD31 cytoplasmic tail at the Y663F and Y686F sites of the immunoreceptor tyrosine-based inhibitory motifs (ITIM) in Crispr/Cas9 transgenic mice alleviate RA. Mechanistically, this results in the downregulation of glycolysis and autophagy pathways. These findings significantly advance our understanding of potential therapeutic strategies for modulating these processes in synovitis and, potentially, other autoimmune diseases.

Deciphering the influence of salinity stress on the biological aniline degradation system: Pollutants degradation performance and microbial response.

In order to evaluate the impact of salinity gradients on the aniline biodegradation system, six reactors at salinity concentrations (0%-5%) were established. The results presented the salinity except for 5% imposed negligible effects on aniline degradation performance. Nitrification had prominent resistance to salinity (0%-1.5%) while were significantly restrained when salinity increased. The total nitrogen (TN) removal efficiency of Z4 (1.5%) was 20.5% higher than Z1 (0%) during the stable operation phase. Moreover, high throughput sequencing analysis showed that halophilic bacterium, such as Halomonas, Rhodococcus, remained greater survival advantages in high salinity system. The substantial enrichment of Flavobacterium, Dokdonella, Paracoccus observed in Z4 ensured its excellent nitrogen removal performance. The close cooperation among dominant functional bacteria was strengthened when salt content was below 1.5% while exceeding 1.5% led to the collapse of metabolic capacity through integrating the toxicity of aniline and high osmotic pressure.

Geographical distribution of MTHFR C677T gene polymorphisms among the reproductive-age women in Chinese Han populations: based on migration.

BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) is essential for the metabolism of folic acid and homocysteine. The MTHFR C677T polymorphism is associated with several disorders. Our study aims to explore the geographical distributions of the MTHFR C677T polymorphism of women in China and how migration affected the polymorphism in Suzhou. METHODS: A total of 7188 women of reproductive age were recruited in Suzhou of the study. Subjects were classified according to their native places after data extraction. MTHFR C677T gene polymorphisms were detected by quantitative PCR with genomic DNA isolated from blood samples. RESULTS: The frequencies of the 677T allele and 677TT genotype were higher in northern China than that in southern China and decreased in geographical gradients from north to south. The frequencies were considerably higher in the migrant population than that in the indigenous population of Suzhou. The migrant population have gradually changed the prevalence in Suzhou. CONCLUSIONS: Our study suggested that the prevalence of MTHFR C677T polymorphisms among women varied across different geographical regions in Chinese Han populations. The 677T allele frequencies of the northern populations were significantly higher than those of the southern populations. The migrant population gradually changed the prevalence of the MTHFR C677T polymorphism in Suzhou.

Influencing risk factors of voriconazole-induced liver injury in Uygur pediatric patients undergoing allogeneic hematopoietic stem cell transplantation.

PURPOSE: We aimed to investigated the influencing risk factors of voriconazole-induced liver injury in Uygur pediatric patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: This was a prospective cohort design study. High-performance liquid chromatography-mass spectrometry was employed to monitor voriconazole concentration. First-generation sequencing was performed to detect gene polymorphisms. Indicators of liver function were detected at least once before and after voriconazole therapy. RESULTS: Forty-one patients were included in this study, among which, 15 patients (36.6%) had voriconazole-induced liver injury. The proportion of voriconazole trough concentration > 5.5 µg·mL-1 patients within the DILI group (40.0%) was significantly higher compared to the control group (15.4%) (p < 0.05). After administration of voriconazole, the values of ALT (103.3 ± 80.3 U/L) and AST (79.9 ± 60.6 U/L) in the DILI group were higher than that in the control group (24.3 ± 24.8 and 30.4 ± 8.6 U/L) (p < 0.05). There was no significant difference between the two groups in genotype and allele frequencies of CYP2C19*2, CYP2C19*3, CYP2C19*17, and UGT1A4 (rs2011425) (p > 0.05). CONCLUSION: There was a significant correlation between voriconazole-induced liver injury and voriconazole trough concentration in high-risk Uygur pediatric patients with allogeneic HSCT.

Utilizing collimated aperture with proton pencil beam scanning (PBS) for stereotactic radiotherapy.

PURPOSE: Proton stereotactic radiosurgery (PSRS) has emerged as an innovative proton therapy modality aimed at achieving precise dose delivery with minimal impact on healthy tissues. This study explores the dosimetric outcomes of PSRS in comparison to traditional intensity-modulated proton therapy (IMPT) by focusing on cases with small target volumes. A custom-made aperture system designed for proton therapy, specifically tailored to small target volumes, was developed and implemented for this investigation. METHODS: A prerequisite mechanical validation through an isocentricity test precedes dosimetric assessments, ensuring the seamless integration of mechanical and dosimetry analyses. Five patients were enrolled in the study, including two with choroid melanoma and three with arteriovenous malformations (AVM). Two treatment plans were meticulously executed for each patient, one utilizing a collimated aperture and the other without. Both plans were subjected to robust optimization, maintaining identical beam arrangements and consistent optimization parameters to account for setup errors of 2 mm and range uncertainties of 3.5%. Plan evaluation metrics encompassing the Heterogeneity Index (HI), Paddick Conformity Index (CIPaddick), Gradient Index (GI), and the R50% index to evaluate alterations in low-dose volume distribution. RESULTS: The comparative analysis between PSRS and traditional PBS treatment revealed no significant differences in plan outcomes, with both modalities demonstrating comparable target coverage. However, collimated apertures resulted in discernible improvements in dose conformity, dose fall-off, and reduced low-dose volume. CONCLUSIONS: This study underscores the advantageous impact of the aperture system on proton therapy, particularly in cases involving small target volumes.

Multifunctional 2D hemin-bridged MOF for the efficient removal and dual-mode detection of organophosphorus pesticides.

The high-residual and bioaccumulation property of organophosphorus pesticides (OPs) creates enormous risks towards the ecological environment and human health, promoting the research for smart adsorbents and detection methods. Herein, 2D hemin-bridged MOF nanozyme (2D-ZHM) was fabricated and applied to the efficient removal and ultrasensitive dual-mode aptasensing of OPs. On the one hand, the prepared 2D-ZHM contained Zr-OH groups with high affinity for phosphate groups, endowing it with selective recognition and high adsorption capacity for OPs (285.7 mg g-1 for glyphosate). On the other hand, the enhanced peroxidase-mimicking biocatalytic property of 2D-ZHM allowed rapid H2O2-directed transformation of 3,3',5,5'-tetramethylbenzidine to oxidic product, producing detectable colorimetric or photothermal signals. Using aptamers of specific recognition capacity, the rapid quantification of two typical OPs, glyphosate and omethoate, was realized with remarkable sensitivity and selectivity. The limit of detections (LODs) of glyphosate were 0.004 nM and 0.02 nM for colorimetric and photothermal methods, respectively, and the LODs of omethoate were 0.005 nM and 0.04 nM for colorimetric and photothermal methods, respectively. The constructed dual-mode aptasensing platform exhibited outstanding performance for monitoring OPs in water and fruit samples. This work provides a novel pathway to develop MOF-based artificial peroxidase and integrated platform for pollutant removal and multi-mode aptasensing.

A magnetic nanozyme platform for bacterial colorimetric detection and chemodynamic/photothermal synergistic antibacterial therapy.

Rapid, convenient, and sensitive detection of bacteria and development of novel antibacterial materials are conducive to accurate treatment of bacterial infection and reducing the generation of drug-resistant bacteria caused by overuse of antibiotics. A dual-function magnetic nanozyme, Fc-MBL@rGO@Fe3O4, has been constructed with broad-spectrum bacterial affinity and good peroxidase-like activity. Detection signal amplification was realized in the presence of 3,3',5,5'-tetramethylbenzidine (TMB) with a detection limit of 26 CFU/mL. In addition, the excellent photothermal properties of Fc-MBL@rGO@Fe3O4 could realize synergistic chemodynamic/photothermal antibacterial therapy. Furthermore, the good bacterial affinity of Fc-MBL@rGO@Fe3O4 enhances the accurate and rapid attack of hydroxyl radical (·OH) on the bacterial membrane and achieves efficient sterilization (100%) at low concentration (40 µg/mL) and mild temperature (47℃). Notably, Fc-MBL@rGO@Fe3O4 has a broad spectrum of antibacterial activity against Gram-negative, Gram-positive, and drug-resistant bacteria. The magnetic nanoplatform integrating detection-sterilization not only meets the need for highly sensitive and accurate detection in different scenarios, but can realize low power density NIR-II light-responsive chemodynamic/photothermal antibacterial therapy, which has broad application prospects.

Use of 1.5-Stage Functional Articulating Hip Spacers for Two-Stage Treatment of Hip Infection.

BACKGROUND: A two-stage treatment is commonly used for chronic hip infections. This study compared the clinical efficacy and complications associated with 1.5-stage functional articulating hip spacers (FAHS) and handmade spacers utilized during two-stage treatment. METHODS: This retrospective study included 50 patients who had hip infections, of which 41 were periprosthetic joint infections, 3 were internal fixation infections, and 6 had septic arthritis. They were divided into two groups according to the spacer type: 23 patients treated with handmade spacers comprising 1 to 2 Kirschner wires as an endoskeleton (group A) and 27 patients treated with 1.5-stage FAHS comprising a cemented femoral stem, metal femoral head, and polyethylene acetabular liner or cemented acetabular cup (group B). Clinical characteristics, surgical data, infection control rate, spacer complications, modified Harris hip, visual analog scale, and 36-item short-form physical functioning scale scores were compared between the groups. All patients were followed up for at least 24 months after the last surgical procedure. RESULTS: No significant differences were noted in the infection eradication rate between the two groups (100 versus 96.30%, P = 1.0). The incidence of mechanical complications, especially spacer fracture, was significantly lower in group B than in group A (P = .044). Hip function and quality of life were significantly better in group B during the interim period. Group B patients had a longer interval time (median 7.40 versus 4.30 months, P = .004) and a lower reimplantation rate than group A patients (42.31 versus 82.61%, P = .004). CONCLUSIONS: The 1.5-stage FAHS surgical technique is feasible for the treatment of hip infection, with a lower mechanical complication rate, better hip function, and better quality of life during the interim period compared to that of handmade spacers. The 1.5-stage FAHS with maintained function could delay or negate the need for second-stage revision.

Phosphorus deficiency-induced cell wall pectin demethylesterification enhances cadmium accumulation in roots of Salix caprea.

Regions affected by heavy metal contamination frequently encounter phosphorus (P) deficiency. Numerous studies highlight crucial role of P in facilitating cadmium (Cd) accumulation in woody plants. However, the regulatory mechanism by which P affects Cd accumulation in roots remains ambiguous. This study aims to investigate the effects of phosphorus (P) deficiency on Cd accumulation, Cd subcellular distribution, and cell wall components in the roots of Salix caprea under Cd stress. The results revealed that under P deficiency conditions, there was a 35.4% elevation in Cd content in roots, coupled with a 60.1% reduction in Cd content in shoots, compared to the P sufficiency conditions. Under deficient P conditions, the predominant response of roots to Cd exposure was the increased sequestration of Cd in root cell walls. The sequestration of Cd in root cell walls increased from 37.1% under sufficient P conditions to 66.7% under P deficiency, with pectin identified as the primary Cd binding site under both P conditions. Among cell wall components, P deficiency led to a significant 31.7% increase in Cd content within pectin compared to P sufficiency conditions, but did not change the pectin content. Notably, P deficiency significantly increased pectin methylesterase (PME) activity by regulating the expression of PME and PMEI genes, leading to a 10.4% reduction in the degree of pectin methylesterification. This may elucidate the absence of significant changes in pectin content under P deficiency conditions and the concurrent increase in Cd accumulation in pectin. Fourier transform infrared spectroscopy (FTIR) results indicated an increase in carboxyl groups in the root cell walls under P deficiency compared to sufficient P treatment. The results provide deep insights into the mechanisms of higher Cd accumulation in root mediated by P deficiency.