Harmonizing tumor mutational burden analysis: Insights from a multicenter study using in silico reference data sets in clinical whole-exome sequencing (WES).

OBJECTIVES: Tumor mutational burden (TMB) is a significant biomarker for predicting immune checkpoint inhibitor response, but the clinical performance of whole-exome sequencing (WES)-based TMB estimation has received less attention compared to panel-based methods. This study aimed to assess the reliability and comparability of WES-based TMB analysis among laboratories under routine testing conditions. METHODS: A multicenter study was conducted involving 24 laboratories in China using in silico reference data sets. The accuracy and comparability of TMB estimation were evaluated using matched tumor-normal data sets. Factors such as accuracy of variant calls, limit of detection (LOD) of WES test, size of regions of interest (ROIs) used for TMB calculation, and TMB cutoff points were analyzed. RESULTS: The laboratories consistently underestimated the expected TMB scores in matched tumor-normal samples, with only 50% falling within the ±30% TMB interval. Samples with low TMB score (<2.5) received the consensus interpretation. Accuracy of variant calls, LOD of the WES test, ROI, and TMB cutoff points were important factors causing interlaboratory deviations. CONCLUSIONS: This study highlights real-world challenges in WES-based TMB analysis that need to be improved and optimized. This research will aid in the selection of more reasonable analytical procedures to minimize potential methodologic biases in estimating TMB in clinical exome sequencing tests. Harmonizing TMB estimation in clinical testing conditions is crucial for accurately evaluating patients' response to immunotherapy.

Association of screen-based sedentary behavior with executive function in school-aged children: A functional near-infrared spectroscopy study.

Screen-based sedentary behavior (SSB) is a significant risk factor for the health of school-aged children, and guidelines recommend limiting SSB to 2 hr per day. This study aimed to examine association and potential mechanisms between SSB and executive function (EF) by comparing Stroop performance and frontal hemodynamic responses between children with and without excessive SSB. A total of 70 children aged 10 to 15 years were recruited and divided into two groups: excessive screen time (≥2 hr/day; n = 35; ES group) and normal screen time (<2 hr/day; n = 35; NS group). The Chinese version of the Adolescent Sedentary Activities Questionnaire was used to assess SSB, whereas EF was evaluated using the Stroop task. The frontal hemodynamic responses during the Stroop task were measured using functional near-infrared spectroscopy. The results indicated that the ES group had lower accuracy, longer reaction times, and greater activation in the bilateral dorsolateral prefrontal cortex (DLPFC) and left pre-supplementary motor area (Pre-SMA) compared with the NS group. Furthermore, significant correlations were observed between Stroop performance and cortical activation in the left DLPFC and Pre-SMA. These findings demonstrate that excessive SSB is associated with poor EF, which may be explained by a decrease in neural efficiency of the left DLPFC and Pre-SMA.

Characterization of Escherichia coli pathogenicity and drug resistance in yolk peritonitis.

Yolk Peritonitis can lead to a rapid decline in egg production, which seriously affects the health of laying hens and the profitability of chicken farms. Escherichia coli (E. coli) is the most common cause of yolk peritonitis in laying hens. In this study, bacterial samples were collected from the ovaries and fallopian tubes of laying hens with suspected yolk peritonitis from a laying farm in Jiangsu Province, and their pathogenicity and drug resistance were investigated. Initially, morphological and biochemical detection methods were employed to isolate and identify the pathogenic bacteria. The results showed that a total of 16 strains of E. coli were isolated from laying hens with yolk peritonitis. Subsequently, the drug resistance and pathogenicity of a randomly selected E. coli strain were analyzed and predicted by genome sequencing technology, and the drug resistance of E. coli was verified by drug sensitivity test and PCR. Finally, the virulence was verified by infection experiment in mice. The study revealed that the egg-yolk peritonitis in laying hens was caused by E. coli infection, and the genome sequencing analysis revealed that the bacteria had multidrug resistance and high virulence. The drug susceptibility testing indicates that E. coli exhibited resistance to aminoglycosides, ß-lactam, macrolides, fluoroquinolones, and sulfonamides. In this study, resistance genes including KdpE, aadA5, APH(3 ")-ID, APH(6)-ID, and TEM-1 were identified, and their expression levels varied across different stages of bacterial growth. The results of virulence analysis indicated a mortality rate of 50% in mice infected with E. coli at a concentration of 2.985 × 107 CFU/mL. E. coli infection resulted in damage to various tissues and organs in mice, with the intestinal tissue structure being the most severely affected. This study provides a reference for the study of drug resistance mechanisms in E. coli and provides valuable insights into the selection of drugs for the treatment of vitelline peritonitis.

A nomogram based on conventional and contrast-enhanced ultrasound radiomics for the noninvasively prediction of axillary lymph node metastasis in breast cancer patients.

Background: This study aimed to investigate whether quantitative radiomics features extracted from conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) of primary breast lesions can help noninvasively predict axillary lymph nodes metastasis (ALNM) in breast cancer patients. Method: A total of 111 breast cancer patients with 111 breast lesions were prospectively enrolled. All the included patients received presurgical CUS screening and CEUS examination and were randomly assigned to the training and validation sets at a ratio of 7:3 (n = 78 versus 33). Radiomics features were respectively extracted based on CUS and CEUS using the PyRadiomics package. The max-relevance and min-redundancy (MRMR) and least absolute shrinkage and selection operator (LASSO) analyses were used for feature selection and radiomics score calculation in the training set. The variance inflation factor (VIF) was performed to check the multicollinearity among selected predictors. The best performing model was selected to develop a nomogram using binary logistic regression analysis. The calibration and clinical utility of the nomogram were assessed. Results: The model combining CUS reported ALN status, CUS radiomics score (CUS-radscore) and CEUS radiomics score (CEUS-radscore) exhibited the best performance. The areas under the curves (AUC) of our proposed nomogram in the training and external validation sets were 0.845 [95% confidence interval (CI), 0.739-0.950] and 0.901 (95% CI, 0.758-1). The calibration curves and decision curve analysis (DCA) demonstrated the nomogram's robust consistency and clinical utility. Conclusions: The established nomogram is a promising prediction tool for noninvasive prediction of ALN status. The radiomics features based on CUS and CEUS can help improve the predictive performance.

The complete chloroplast genome sequence of Calystegia hederacea Wall. in Roxb. 1824 (Convolvulaceae) in Enshi, Hubei.

Calystegia hederacea Wall. in Roxb. 1824 is a perennial herbaceous vine in the family Convolvulaceae and has several biological effects. Herein, we reported the first complete chloroplast genome of C. hederacea. The chloroplast genome sequence was 152,057 bp in length, comparing a large single-copy (LSC) region of 87,891 bp, a small single-copy (SSC) region of 19,866 bp, and a pair of inverted repeat (IR) regions of 22,150 bp. This sequenced chloroplast genome contained 126 predicted genes, including 81 protein-coding genes, 37 tRNA genes, and eight rRNA genes, and the total GC content of the chloroplast genome was 37.79%. Phylogenetic analysis revealed that C. hederacea was closely related to C. soldanella. The chloroplast genome presented in this study will enrich the genome information of the genus Calystegia and provide deeper insights into the evolution study of the family Convolvulaceae.

Tailored different sizes of quantum dot nanobeads for sensitive and quantitative detection based on the competition fluorescence-linked immunosorbent assay platform.

Highly stable and multicolor photoluminescent (PL) quantum dots (QDs) have attracted widespread attention as ideal probe materials in the field of in vitro diagnostics (IVD), especially the fluorescence-linked immunosorbent assay (FLISA), due to their advantages of high-throughput, high stability, and high sensitivity. However, the size of QDs as fluorescent probes have significant effects on antigen-antibody performance. Therefore, it is critical to design suitable QDs for obtain excellent quantitative detection-based biosensors. In this paper, we prepared different sizes of aqueous QDs (30 nm, 116 nm, 219 nm, and 320 nm) as fluorescent probes to optimize the competitive FLISA platform. The SARS-CoV-2 neutralizing antibody (NTAB) assay was used as an example, and it was found that the size of the QDs has a significant impact on the antigen-antibody binding efficiency and detection sensitivity in competitive FLISA platform. The results showed that these QD nanobeads (QBs, ∼219 nm) could be used as a labeled probe for competitive FLISA, with half-maximal inhibitory concentration (IC50) of 1.34 ng/mL and limit of detection (LOD) of 0.21 pg/mL for NTAB detection. More importantly, the results showed good specificity and accuracy, and the QB219 probe was able to efficiently bind NTAB without interference from other substances in the serum. Given the above advantages, the nanoprobe material (∼200 nm) offers considerable potential as a competitive FLISA platform in the field of IVD.

Comparing percutaneous transhepatic papillary balloon dilation with endoscopic retrograde cholangiopancreatography in elderly patients for common bile duct stones: a 3-year retrospective study.

PURPOSE: To assess the safety and effectiveness of PTPBD for CBD stones in the elderly population. METHODS: Patients aged 60 years or older, who underwent PTPBD or ERCP for CBD stones between January 2021 and December 2023, were included in this study and divided into either the PTPBD group or the ERCP group based on the procedure they underwent. Baseline characteristics, intraoperative and postoperative outcomes were collected and analyzed using SPSS 25.0. RESULTS: A total of 145 cases were enrolled in the study. In terms of intraoperative complications, one patient in the ERCP group experienced hemorrhaging, while one patient in the PTPBD group experienced acute pain. However, neither of these patients were in a serious condition and only required observation. Stone removal procedures were successfully conducted in approximately 95% of cases in both the PTPBD and ERCP groups (95.8 and 94.8%, respectively; P > 0.999). ERCP failures were observed in one patient with a previous Billroth II anastomosis and two patients with unconventional anatomy of the esophagus and stomach. There was no statistically significant difference in postoperative complications between the PTPBD group and the ERCP group (P > 0.05). The length of hospital stays did not differ between the PTPBD group and the ERCP group (P = 0.537 > 0.05). CONCLUSION: PTPBD can be used in patients who have complicated anatomical issues that make the ERCP procedure difficult. In comparison, PTPBD is a similarly safe, effective, and minimally invasive technique for extracting CBD stones in elderly patients.

Beneficial Effects of Oxymatrine from Sophora flavescens on Alleviating by Improving Inflammation and Ferroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Sophora flavescens is often used in traditional Chinese medicine for skin issues, diarrhea, and vaginal itching (Plant names have been checked with http://www.the plant list.org on Feb 22th, 2024). Oxymatrine (OY), a major bioactive compound from Sophora flavescens, is commonly used in China to treat ulcerative colitis, but its mechanisms are still unclear. AIM OF THE STUDY: Recent studies have found that the crosstalk between ferroptosis and inflammation is an important mechanism in the pathogenesis of UC. The aim of this study was to investigate the potential underlying mechanisms of OY treatment on DSS-induced ulcerative colitis, specifically focusing on the processes of ferroptosis and inflammation. MATERIALS AND METHODS: Bioinformatics methods were used to identify key targets of OY for ferroptosis and inflammation in ulcerative colitis, based on GEO data and FerrDb database. Then, 4% DSS solution was used to induce UC model. OY's impact on morphological changes was assessed using colon views, Hematoxylin and eosin (HE) staining, and transmission electron microscopy (TEM). Ferroptosis phenotype index and inflammations factors were detected by ELISA or chem-bio detection kits The screen out hub related genes about ferroptosis and inflammation were verified by RT-PCR, immunohistochemistry (IHC), immunofluorescence (IF), and western blotting (WB) respectively. RESULTS: Bioinformatics results show that there are 16 key target genes involved in ferroptosis and inflammation interaction of OY treatment for UC, such as IL6, NOS2, IDO1, SOCS1, and DUOX. The results of animal experiments show that OY could depress inflammatory factors (IL-1ß, IL-6, TNF-α, HMGB1, and NLRP3) and reduce iron deposition (Fe2+, GSH, and ferritin). Additionally, OY suppressed the hub genes or proteins expression involved in ferroptosis and inflammation, including IL-1ß, IL-6, NOS2, HIF1A, IDO1, TIMP1, and DUOX2. CONCLUSION: This present study combines bioinformatics, molecular biology, and animal experimental research evidently demonstrated that OY attenuates UC by improving ferroptosis and inflammation, mainly target to the expression of IL-1ß, IL-6, NOS2, HIF1A, IDO1, TIMP1, and DUOX2.

Placental Malaria Induces a Unique Placental Methylation Profile Associated with Fetal Growth Restriction.

Background: Fetal growth restriction (FGR) is associated with perinatal death and other adverse birth outcomes, as well as long term complications including increased childhood morbidity, abnormal neurodevelopment, and cardio-metabolic diseases in adulthood. FGR has been associated with placental epigenetic reprogramming, which may mediate these long term outcomes. Placental malaria (PM) is the leading cause of FGR globally, but the impact on placental epigenetics is unknown. We hypothesized that methylomic profiling of placentas from non-malarial and malarial FGR would reveal common and distinct mechanistic pathways associated with FGR. Results: We used a methylation array to compare the CpG profiles between FGR from a cohort with no malaria exposure and a cohort of pregnancies complicated by both PM and FGR. Non-malarial FGR was associated with 65 differentially methylated CpGs, whereas PM-FGR was associated with 133 DMCs, compared to their corresponding controls. One DMC (cg16389901) was commonly hypomethylated in both groups, corresponding to the promoter region of BMP4 . Comparison of FGR vs. PM-FGR identified 522 DMCs between these two groups, which was not attributable to geographic location or different cellular compositions of these two groups. Conclusion: Placentas from pregnancies with PM-associated FGR showed distinct methylation profiles as compared to non-malarial FGR, suggesting novel epigenetic reprogramming in response to malaria. There may be distinct long-term health outcomes in FGR pregnancies also complicated by PM.

The complete chloroplast genome sequence of Hydrocotyle vulgaris L. (Araliaceae).

Hydrocotyle vulgaris is a perennial wetland clonal plant in the Araliaceae family, which was introduced to China as an ornamental plant in the 1990s. Although H. vulgaris is now considered a potential invasiveness species in China, it also plays a significant role in the remediation of water pollution. Here, we reported its complete chloroplast genome and analyzed the basic characteristics. The chloroplast genome was 153,165 bp in length, including a pair of inverted repeat (IR) regions of 25,072 bp separated by a large single-copy (LSC) region of 84,291 bp and a small single-copy (SSC) region of 18,730 bp. The H. vulgaris chloroplast genome contained 132 predicted genes, and its overall GC content was 37.60%. Phylogenetic analysis revealed that H. vulgaris was closely related to H. verticillata. The H. vulgaris chloroplast genome presented in this study will lay a foundation for further genetic and genomic studies of the genus Hydrocotyle.

Molecular mechanism of Danxiong Tongmai Granules in treatment of coronary heart disease.

BACKGROUND: Danxiong Tongmai Granules (DXTMG) are widely utilized in treating coronary heart disease (CHD) in China. This study aims to explore the molecular mechanisms underlying the therapeutic effects of DXTMG on CHD by employing a network pharmacology approach, complemented with experimental validation. METHODS: Traditional Chinese Medicine (TCM) compounds and targets were identified via searches in the BATMAN-TCM database, and the GeneCards database was used to obtain the main target genes involved in CHD. We combined disease targets with the drug targets to identify common targets. The "TCM-compound-target" network was plotted using Cytoscape 3.7.2 software and a protein-protein interaction (PPI) network was constructed using the STRING database from which core targets were obtained. Gene ontology (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed for common drug-disease targets using R Version 4.0.4 (64 bit) software. Molecular docking of core protein-small molecule ligand interaction was modeled using AutoDock software. A molecular dynamics simulation was conducted on the optimal protein-small molecule complex identified through molecular docking, using Amber18 software. The rat model for myocardial ischemia was established through pre-gavage administration of DXTMG, followed by dorsal hypodermic injection of isoprenaline. Myocardial tissues from the rats were analyzed using hematoxylin and eosin (HE) staining and Masson's trichrome staining. Relevant targets were validated by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. RESULTS: 162 potential targets of DXTMG involved in CHD were identified. These included INS, ALB, IL-6 and TNF according to PPI network studies. GO enrichment analysis identified a total of 3365 GO pathways, including 3049 biological process pathways (BP) concerned with the heart and circulatory system; 109 cellular component (CC) pathways, including cation channels and membrane rafts and 207 molecular function (MF) pathways related to receptor ligands and activators. KEGG analysis revealed a total of 137 pathways (P < 0.05), including those related to AGE-RAGE signaling associated with diabetic complications, fluid shear stress and atherosclerosis. The results of molecular docking and molecular dynamics simulations demonstrated the robust binding affinity between the compounds and target proteins. Animal experiment findings indicated that, compared with the model group, the DXTMG group effectively ameliorated inflammation and fibrosis in rat myocardial tissues, reduced LDH, cTn-I, and MDA levels (P < 0.05, P < 0.01), elevated SOD and GSH-PX levels (P < 0.05), and reduced the percentage of positive area for IL-6 and TNF-α (P < 0.05). CONCLUSION: This study preliminarily suggests that DXTMG can modulate oxidative stress, inflammation response, and cardiomyocyte regulation, thereby mitigating the onset and progression of CHD.

Hypoxia-related THBD+ macrophages as a prognostic factor in glioma: Construction of a powerful risk model.

Glioma is a prevalent malignant tumour characterized by hypoxia as a pivotal factor in its progression. This study aims to investigate the impact of the most severely hypoxic cell subpopulation in glioma. Our findings reveal that the THBD+ macrophage subpopulation is closely associated with hypoxia in glioma, exhibiting significantly higher infiltration in tumours compared to non-tumour tissues. Moreover, a high proportion of THBD+ cells correlates with poor prognosis in glioblastoma (GBM) patients. Notably, THBD+ macrophages exhibit hypoxic characteristics and epithelial-mesenchymal transition features. Silencing THBD expression leads to a notable reduction in the proliferation and metastasis of glioma cells. Furthermore, we developed a THBD+ macrophage-related risk signature (THBDMRS) through machine learning techniques. THBDMRS emerges as an independent prognostic factor for GBM patients with a substantial prognostic impact. By comparing THBDMRS with 119 established prognostic features, we demonstrate the superior prognostic performance of THBDMRS. Additionally, THBDMRS is associated with glioma metastasis and extracellular matrix remodelling. In conclusion, hypoxia-related THBD+ macrophages play a pivotal role in glioma pathogenesis, and THBDMRS emerges as a potent and promising prognostic tool for GBM, contributing to enhanced patient survival outcomes.

Transformation of marginal zone lymphoma into high-grade B-cell lymphoma expressing terminal deoxynucleotidyl transferase: A case report.

BACKGROUND: High-grade B-cell lymphoma (HGBL) is an unusual malignancy that includes myelocytomatosis viral oncogene (MYC), B-cell lymphoma-2 (BCL-2), and/or BCL-6 rearrangements, termed double-hit or triple-hit lymphomas, and HGBL-not otherwise specific (HGBL-NOS), which are morphologically characteristic of HGBL but lack MYC, BCL-2, or BCL-6 rearrangements. HGBL is partially transformed by follicular lymphoma and other indolent lymphoma, with few cases of marginal zone lymphoma (MZL) transformation. HGBL often has a poor prognosis and intensive therapy is currently mainly advocated, but there is no good treatment for these patients who cannot tolerate chemotherapy. CASE SUMMARY: We reported a case of MZL transformed into HGBL-NOS with TP53 mutation and terminal deoxynucleotidyl transferase expression. Gene analysis revealed the gene expression profile was identical in the pre- and post-transformed tissues, suggesting that the two diseases are homologous, not secondary tumors. The chemotherapy was ineffective and the side effect was severe, so we tried combination therapy including venetoclax and obinutuzumab. The patient tolerated treatment well, and reached partial response. The patient had recurrence of hepatocellular carcinoma and died of multifunctional organ failure. He survived for 12 months after diagnosis. CONCLUSION: Venetoclax combined with obinutuzumab might improve the survival in some HGBL patients, who are unsuitable for chemotherapy.

Factors influencing length of stay and costs in inpatient cases of human brucellosis as the primary diagnosis over a decade in Beijing, China.

Aims: In the year 2021, human brucellosis ranked fifth in terms of the number of cases among all statutorily notifiable infectious diseases in China, thus remaining a significant concern for public health. This study aims to provide insights into the financial burden of human brucellosis by examining hospital stays and associated costs for affected individuals. Methods: In this retrospective study, we gathered updated data from 467 inpatient cases primarily diagnosed with human brucellosis at eight major tertiary hospitals in Beijing, China, spanning from 2013 to 2023. To comprehensively explore the economic impact on individuals, we not only analyzed the duration of hospital stays and total costs but also examined various charge types, including drug, lab test, medical imaging, medical treatment, surgical procedures, medical supplies and consumables, inpatient bed care, nursing services, and other services costs. Statistical analysis was employed to compare differences among gender, age, ethnicity, type of health insurance, condition at admission, comorbidity index, the performance of surgery, and the site of infection. Results: Both the length of stay and total cost exhibited significant variations among insurance, surgery, and infection site groups. Utilization categories demonstrated significant differences between patients who underwent surgery and those who did not, as well as across different infection sites. Furthermore, multiple linear regression analysis revealed that the condition at admission, Elixhauser comorbidity index, infection site, and surgery influenced both hospital stay and total cost. In addition, age and insurance type were associated with total costs. Conclusion: By delving into various utilization categories, we have addressed a significant gap in the literature. Our findings provide valuable insights for optimizing the allocation and management of health resources based on the influencing factors identified in this study.

Nitrogen can substitute helium as a mobile phase in the analysis of wastewater treatment matrices for persistent organic pollutants by gas chromatography - electron capture detection system.

Municipal wastewater treatment plants are required to monitor persistent organic pollutants (POPs) in their wastewater treatment related discharges and to assess the impact of the discharges on the environment and public health. One tool for monitoring chlorinated organic pollutants particularly is a gas chromatographic (GC) system coupled to a pair of halogen-specific electron capture detectors (ECDs) with helium (He) as the mobile phase. He supplies, however, has become inconsistent and unreliable lately. In its place, N2 gas is evaluated in this study as a potential substitute for He in quantifying organochlorine pesticides, polychlorinated biphenyls, chlordane congeners and toxaphene in wastewater treatment related matrices (influent, effluent, benthic sediment, mussel tissue, and biosolids/sludge). N2 is inert, inexpensive and requires no additional hardware to incorporate into the basic functions of a GC-ECD. Our results show that, with the usual data quality controls (blank, laboratory control, matrix spike/duplicate and proficiency testing samples, and the fact that certified reference materials data met requirements), N2 can replace He for regulatory purposes. And when necessary, the N2-based retention times (tN) can be predicted reliably from He-based retention times (tHe), irrespective of column chemistry or POPs (here: tN = 1.90tHe + 0.04, R2 = 0.996).

In vitro simulated digestion and fermentation characteristics of pectic polysaccharides from fresh passion fruit (Passiflora edulis f. flavicarpa L.) peel.

In this study, two pectic polysaccharides (PFP-T and PFP-UM) were extracted from fresh passion fruit peels using three-phase partitioning (TPP) and sequential ultrasound-microwave-assisted TPP methods, respectively, and their effects on the in vitro gastrointestinal digestion and fecal fermentation characteristics were examined. The results indicate that gastrointestinal digestion has a minimal effect on the physicochemical and structural characteristics of PFP-T and PFP-UM. However, during in vitro fecal fermentation, both undigested PFP-T and PFP-UM are significantly degraded and utilized by intestinal microorganisms, showing increased the total relative abundance of Firmicutes and Bacteroidota in the intestinal flora. Notably, compared with PFP-UM, PFP-T better promoted the reproduction of beneficial bacteria such as Prevotella, Megasphaera and Dialister, while suppressed the growth of harmful genera including Escherichia-Shigella, producing higher content of short-chain fatty acids. Therefore, our findings suggest that PFP-T derived from passion fruit peel has potential as a dietary supplement for promoting intestinal health.

T6SS nuclease effectors in Pseudomonas syringae act as potent antimicrobials in interbacterial competition.

Type VI secretion system (T6SS) is a potent weapon employed by various Pseudomonas species to compete with neighboring microorganisms for limited nutrients and ecological niches. However, the involvement of T6SS effectors in interbacterial competition within the phytopathogen Pseudomonas syringae remains unknown. In this study, we examined two T6SS clusters in a wild-type P. syringae MB03 and verified the involvement of one cluster, namely, T6SS-1, in interbacterial competition. Additionally, our results showed that two T6SS DNase effectors, specifically Tde1 and Tde4, effectively outcompeted antagonistic bacteria, with Tde4 playing a prominent role. Furthermore, we found several cognate immunity proteins, including Tde1ia, Tde1ib, and Tde4i, which are located in the downstream loci of their corresponding effector protein genes and worked synergistically to protect MB03 cells from self-intoxication. Moreover, expression of either Tde1 or C-terminus of Tde4 in Escherichia coli cells induced DNA degradation and changes in cell morphology. Thus, our results provide new insights into the role of the T6SS effectors of P. syringae in the interbacterial competition in the natural environment. IMPORTANCE: The phytopathogen Pseudomonas syringae employs an active type VI secretion system (T6SS) to outcompete other microorganisms in the natural environment, particularly during the epiphytic growth in the phyllosphere. By examining two T6SS clusters in P. syringae MB03, T6SS-1 is found to be effective in killing Escherichia coli cells. We highlight the excellent antibacterial effect of two T6SS DNase effectors, namely, Tde1 and Tde4. Both of them function as nuclease effectors, leading to DNA degradation and cell filamentation in prey cells, ultimately resulting in cell death. Our findings deepen our understanding of the T6SS effector repertoires used in P. syringae and will facilitate the development of effective antibacterial strategies.

Association of osteoporotic fractures of femoral neck and femoral neck geometric parameters in native Chinese women.

BACKGROUND: Although it is generally believed that the femoral neck fracture is related to the femoral neck geometric parameters (FNGPs), the association between the risk of osteoporotic fracture of the femoral neck and FNGPs in native Chinese women is still unclear. METHODS: A total of 374 female patients (mean age 70.2 ± 9.32 years) with osteoporotic fracture of the femoral neck, and 374 non-fracture control groups were completely matched with the case group according to the age ratio of 1:1. Using DXA bone densitometer to measured eight FNGPs: the outer diameter (OD), cross-sectional area (CSA), cortical thickness (CT), endocortical diameter (ED), buckling ratio (BR), section modulus (SM), cross-sectional moment of inertia (CSMI), and compressive strength index (CSI) at the narrowest point of the femoral neck. RESULTS: Compared with the control group, the average values of OD (2.9%), ED (4.5%), and BR (26.1%) in the patient group significantly increased (p = 0.015 to < 0.001), while CSA (‒15.3%), CT (‒18.2%), SM (‒10.3%), CSMI (‒6.4%), and CSI (‒10.8%) significantly decreased (all p < 0.001). The prevalence of osteoporosis in the lumbar spine, femoral neck, and total hip was, respectively, 82%, 81%, and 65% in fracture patients. Cox proportional hazard model analysis showed that in the age adjusted model, the fracture hazard ratio (HR) of CSA, CT, BR, SM, and CSI significantly increased (HRs = 1.60‒8.33; 95% CI = 1.08‒16.6; all p < 0.001). In the model adjusted for age and femoral neck BMD, HRs of CT (HRs = 3.90‒8.03; 95% CI = 2.45‒15.1; all p < 0.001) and BR (HRs = 1.62‒2.60; 95% CI = 1.20‒5.44; all p < 0.001) were still significantly increased. CONCLUSION: These results suggest that the majority of osteoporotic fractures of the femoral neck of native Chinese women occur in patients with osteoporosis. CT thinning or BR increase of FNGPs may be independent predictors of fragility fracture of femoral neck in native Chinese women unrelated to BMD.

Nematicidal activity and action mode of a methyl-accepting chemotaxis protein from Pseudomonas syringae against Caenorhabditis elegans.

The conventional phytopathogen Pseudomonas syringae reportedly possesses several virulence determinants against Caenorhabditis elegans; however, their action mechanisms remain elusive. This study reports the nematicidal activity and action receptor of a methyl-accepting chemotaxis protein (MCP03) of a wild-type P. syringae MB03 against C. elegans. Purified MCP03 exhibited nematicidal toxicity against C. elegans at a half-lethal concentration of 124.4 µg mL-1, alongside detrimental effects on the growth and brood size of C. elegans. Additionally, MCP03-treated worms exhibited severe pathological destruction of the intestine and depressed wrinkles of the cuticle. Yeast two-hybrid assays identified a subunit of COP9 signalosome, namely CSN-5, which functioned as an MCP03 action receptor. In vitro pull-down verified the binding interaction between MCP03 and CSN-5. RNA interference assays confirmed that MCP03 antagonizes CSN-5, thereby adversely affecting the brood size and cuticle integrity of C. elegans. Following MCP03 infection, the expression of genes related to reproduction, growth, and cuticle formation, such as kgb-1, unc-98, and col-117, was considerably downregulated, indicating pathological changes in MCP03-treated nematodes. Therefore, we proposed that MCP03 antagonizes CSN-5, causing lethality as well as detrimental effects on the fertility, growth, and morphogenesis of C. elegans, which can provide new insights into the signaling pathways and mechanisms underlying the nematicidal action of MCP03 toward C. elegans.