Selenobacteria-mediated Se transformation and uptake involving the unique genetic code.

Selenium (Se) is a crucial micronutrient for human health. Plants are the primary source of Se for humans. Selenium in the soil serves as the primary source of Se for plants. The soil contains high total Se content in large areas in Guangxi, China. However, the available Se is low, hindering Se uptake by plants. Microorganisms play a pivotal role in the activation of Se in the soil, thereby enhancing its uptake by plants. In this study, selenobacteria were isolated from Se-rich soils in Guangxi. Then two selenobacteria strains, YLB1-6 and YLB2-1, representing the highest (30,000 µg/mL) and lowest (10,000 µg/mL) Se tolerance levels among the Se-tolerant bacteria, were selected for subsequent analysis. Although the two selenobacteria exhibited distinct effects, they can significantly transform Se species, resulting in a decrease in the soil residual Se (RES-Se) content while concurrently increasing the available Se (AVA-Se) content. Selenobacteria also enhance the transformation of Se valencies, with a significant increase observed in soluble Se6+ (SOL-Se6+). Additionally, selenobacteria can elevate the pH of acidic soil. Selenobacteria also promote the uptake of Se into plants. After treatment with YLB1-6 and YLB2-1, the Se content in the aboveground part of Chinese flowering cabbage increased by 1.96 times and 1.77 times, respectively, while the Se accumulation in the aboveground part of the plant significantly increased by 104.36% and 81.69%, respectively, compared to the control. Further whole-genome sequencing revealed the genetic difference between the two selenobacteria. Additionally, 46 and 38 candidate genes related to selenium utilization were identified from YLB1-6 and YLB2-1, respectively. This work accelerates our understanding of the potential molecular mechanism of Se biofortification by selenobacteria. It also provides microorganisms and gene targets for improving crop varieties or microorganisms to exploit the rich Se source in soil.

Spatially Confined π-Complexation within Pore-Space-Partitioned Metal-Organic Frameworks for Enhanced Light Hydrocarbon Separation and Purification.

Ultramicroporous metal-organic frameworks (MOFs) are demonstrated to be advantageous for the separation and purification of light hydrocarbons such as C2H2, C2H4, and CH4. The introduction of transition metal sites with strong π-complexation affinity into MOFs is more effective than other adsorption sites for the selective adsorption of π-electron-rich unsaturated hydrocarbon gases from their mixtures. However, lower coordination numbers make it challenging to produce robust MOFs directly utilizing metal ions with π-coordination activity, such as Cu+, Ag+, and Pd2+. Herein, a series of novel π-complexing MOFs (SNNU-33s) with a pore size of 4.6 Å are precisely constructed by cleverly introducing symmetrically matched C3-type [Cu(pyz)3] (pyz = pyrazine) coordinated fragments into 1D hexagonal channels of MIL-88 prototype frameworks. Benifit from the spatial confinement combined with π-complex-active Cu+ of [Cu(pyz)3], pore-space-partitioned SNNU-33 MOFs all present excellent C2H2/CH4, C2H4/CH4, and CO2/CH4 separation ability. Notably, the optimized SNNU-33b adsorbent demonstrates top-level IAST selectivity values for C2H2/CH4 (597.4) and C2H4/CH4 (69.8), as well as excellent breakthrough performance. Theoretical calculations further reveal that such benchmark light hydrocarbon separation and purification ability is mainly ascribed to the extra-strong binding affinity between Cu+ and π-electron donor molecules via a spatially confined π-complexation process.

Light-induced photoluminescence enhancement in chiral CdSe quantum dot films.

Chiral quantum dots (QDs) are promising materials applied in many areas, such as chiral molecular recognition and spin selective filter for charge transport, and can be prepared by facile ligand exchange approaches. However, ligand exchange leads to an increase in surface defects and reduces the efficiencies of radiative recombination and charge transport, which restricts further applications. Here, we investigate the light-induced photoluminescence (PL) enhancement in chiral L- and D-cysteine CdSe QD thin films, providing a strategy to increase the PL. The PL intensity of chiral CdSe QD films can be significantly enhanced over 100 times by continuous UV laser irradiation, indicating a strong passivation of surface defects upon laser irradiation. From the comparative measurements of the PL intensity evolutions in vacuum, dry oxygen, air, and humid nitrogen atmospheres, we conclude that the mechanism of PL enhancement is photo-induced surface passivation with the assistance of water molecules.

Integrating iron metabolism-related gene signature to evaluate prognosis and immune infiltration in nasopharyngeal carcinoma.

BACKGROUND: Dysregulation of iron metabolism has been shown to have significant implications for cancer development. We aimed to investigate the prognostic and immunological significance of iron metabolism-related genes (IMRGs) in nasopharyngeal carcinoma (NPC). METHODS: Multiple Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets were analyzed to identify key IMRGs associated with prognosis. Additionally, the immunological significance of IMRGs was explored. RESULTS: A novel risk model was established using the LASSO regression algorithm, incorporating three genes (TFRC, SLC39A14, and ATP6V0D1).This model categorized patients into low and high-risk groups, and Kaplan-Meier analysis revealed significantly shorter progression-free survival for the high-risk group (P < 0.0001). The prognostic model's accuracy was additionally confirmed by employing time-dependent Receiver Operating Characteristic (ROC) curves and conducting Decision Curve Analysis (DCA). High-risk patients were found to correlate with advanced clinical stages, specific tumor microenvironment subtypes, and distinct morphologies. ESTIMATE analysis demonstrated a significant inverse relationship between increased immune, stromal, and ESTIMATE scores and lowered risk score. Immune analysis indicated a negative correlation between high-risk score and the abundance of most tumor-infiltrating immune cells, including dendritic cells, CD8+ T cells, CD4+ T cells, and B cells. This correlation extended to immune checkpoint genes such as PDCD1, CTLA4, TIGIT, LAG3, and BTLA. The protein expression patterns of selected genes in clinical NPC samples were validated through immunohistochemistry. CONCLUSION: This study presents a prognostic model utilizing IMRGs in NPC, which could assist in assessing patient prognosis and provide insights into new therapeutic targets for NPC.

A radiomics signature derived from CT imaging to predict MSI status and immunotherapy outcomes in gastric cancer: a multi-cohort study.

BACKGROUND: Accurate microsatellite instability (MSI) testing is essential for identifying gastric cancer (GC) patients eligible for immunotherapy. We aimed to develop and validate a CT-based radiomics signature to predict MSI and immunotherapy outcomes in GC. METHODS: This retrospective multicohort study included a total of 457 GC patients from two independent medical centers in China and The Cancer Imaging Archive (TCIA) databases. The primary cohort (n = 201, center 1, 2017-2022), was used for signature development via Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression analysis. Two independent immunotherapy cohorts, one from center 1 (n = 184, 2018-2021) and another from center 2 (n = 43, 2020-2021), were utilized to assess the signature's association with immunotherapy response and survival. Diagnostic efficiency was evaluated using the area under the receiver operating characteristic curve (AUC), and survival outcomes were analyzed via the Kaplan-Meier method. The TCIA cohort (n = 29) was included to evaluate the immune infiltration landscape of the radiomics signature subgroups using both CT images and mRNA sequencing data. RESULTS: Nine radiomics features were identified for signature development, exhibiting excellent discriminative performance in both the training (AUC: 0.851, 95%CI: 0.782, 0.919) and validation cohorts (AUC: 0.816, 95%CI: 0.706, 0.926). The radscore, calculated using the signature, demonstrated strong predictive abilities for objective response in immunotherapy cohorts (AUC: 0.734, 95%CI: 0.662, 0.806; AUC: 0.724, 95%CI: 0.572, 0.877). Additionally, the radscore showed a significant association with PFS and OS, with GC patients with a low radscore experiencing a significant survival benefit from immunotherapy. Immune infiltration analysis revealed significantly higher levels of CD8 + T cells, activated CD4 + B cells, and TNFRSF18 expression in the low radscore group, while the high radscore group exhibited higher levels of T cells regulatory and HHLA2 expression. CONCLUSION: This study developed a robust radiomics signature with the potential to serve as a non-invasive biomarker for GC's MSI status and immunotherapy response, demonstrating notable links to post-immunotherapy PFS and OS. Additionally, distinct immune profiles were observed between low and high radscore groups, highlighting their potential clinical implications.

Case report: Urachal perivascular epithelioid cell tumor.

Background: Urachal tumors are rare in clinical practice, among which urachal adenocarcinoma is the most common. In this study, we report a rare case of urachal perivascular epithelioid cell tumor to improve our understanding of the disease. Case presentation: A 26-year-old male patient was hospitalized for lower abdominal pain. The US showed a hypoechoic mass measuring 26mm × 18mm in the superior aspect of the bladder. MRI showed an irregular mass located anterior to the bladder roof, near the midline. The tumor exhibited hypointense on T1WI and heterogeneous hyperintense on T2WI. Additionally, contrast-enhanced T1-weighted imaging revealed obvious ring enhancement of the tumor. The patient underwent surgical resection of the urachal tumor, with subsequent pathological examination revealing a diagnosis of urachal PEComa. Following surgery, the patient underwent regular follow-up assessments, with no evidence of recurrence or metastasis observed after three and a half years. Conclusions: Urachal PEComa is a rare mesenchymal tumor that presents challenges in diagnosis through imaging and clinical symptoms. Definitive diagnosis relies on pathological and immunohistochemical analysis. Due to the rarity of urachal PEComa, prognosis assessment necessitates long-term follow-up and evaluation of more cases.

Development and validation of a nomogram for Siewert II esophagogastric junction adenocarcinoma: a retrospective analysis.

Background: Due to the complex histological type and anatomical structures, there has been considerable debate on the classification of adenocarcinoma of the esophagogastric junction (AEG), especially Siewert II AEG. Furthermore, neither the American Joint Committee on Cancer (AJCC) 7th tumor-node-metastasis (TNM) [esophageal adenocarcinoma (E) or gastric cancer (G)] nor the AJCC 8th TNM (E or G) accurately predicted the prognosis of patients with Siewert II AEG. Objective: This study aimed to investigate the factors influencing the survival and prognosis of patients with Siewert II AEG and establish a new and better prognostic predictive model. Design: A retrospective study. Methods: Patients with Siewert II AEG, retrieved from the Surveillance, Epidemiology, and End Results (SEER) databases, were assigned to the training set. Patients retrieved from a single tertiary medical center were assigned to the external validation set. Significant variables were selected using univariate and multivariate Cox regression analyses to construct the nomogram. Nomogram models were assessed using the concordance index (C-index), a calibration plot, decision curve analysis (DCA), and external validation. Results: Age, tumor grade, and size, as well as the T, N, and M stages, were included in the nomograms. For the SEER training set, the C-index of the nomogram was 0.683 (0.665-0.701). The C-index of the nomogram for the external validation set was 0.690 (0.653-0.727). The calibration curve showed good agreement between the nomogram estimations and actual observations in both the training and external validation sets. The DCA showed that the nomogram was clinically useful. Conclusion: The new predictive model showed significant accuracy in predicting the prognosis of Siewert II AEG.

Paired Box 5 (PAX5) Gene Has Diagnostic and Prognostic Potential in Nasopharyngeal Carcinoma.

Purpose: Paired Box 5 (PAX5) is a transcription factor that is widely associated with carcinogenesis. PAX5 can maintain Epstein-Barr virus (EBV) latency in B cells, while a close association exists between EBV infection and nasopharyngeal carcinoma (NPC). However, there are very few reports on the correlation between PAX5 and NPC development. The aim of this study was to investigate the role of PAX5 in NPC. Patients and Methods: The clinical value and prognostic significance of PAX5 in NPC and the association with PAX5 expression and immune cell infiltration were analyzed by multiple GEO datasets. In vivo and in vitro experiments including real-time PCR, Western blot, CCK-8 assay, and methylation sequencing were used to validate the results of bioinformatics analysis. Results: The expression of PAX5 was significantly reduced in NPC tissues, with the low expression being correlated with advanced clinical stage, low tumor mutation burden and immune activation, high relative expression of EBV, poor survival for NPC patients. PAX5 exhibited excellent diagnostic performance and had potential as a predictive factor for response to the immune checkpoint inhibitors therapy. Enrichment analysis suggested that the low expression of PAX5 was associated with the dysregulation of Hippo and Wnt signaling pathways. The promoter of PAX5 gene was hypermethylated in NPC tissues. Furthermore, the in vitro and in vivo experiments revealed that NPC tissue and cell lines had low mRNA expression levels of PAX5, the PAX5 promoter was hypermethylated in NPC cell lines, and PAX5 overexpression inhibited NPC cell proliferation and tumor growth in nude mice. Conclusion: PAX5 may be a tumor suppressor and serve as a novel potential diagnostic and prognostic marker for NPC.

Zhilong Huoxue Tongyu capsule alleviates myocardial fibrosis by improving endothelial cell dysfunction.

Background and aim: Zhilong Huoxue Tongyu (ZL) capsule is a classical traditional Chinese medicine (TCM) with satisfactory curative effects. Endothelial cell (EC) dysfunction plays an important role during myocardial fibrosis (MF). But the therapeutic effect of ZL capsule on EC dysfunction remains unknown in the development of MF. This study aims to investigate the effect of ZL capsule on EC dysfunction during MF in vivo. Experimental procedure: The model of MF is established in vivo by injecting isoproterenol for 14 days, simultaneously, we examined the therapeutic effect of ZL capsule on MF in vivo. An integrative approach combining biomarker examination, echocardiography and myocardial fibrosis condition using Hematoxylin-eosin staining, Masson staining, and Sirius red staining were performed to assess the efficacy of ZL capsule against MF. Subsequently, comprehensive immunofluorescence staining was performed to evaluate the therapeutic effect of ZL capsule on EC dysfunction. Results and conclusion: Prior to experiments, analysis of the published single-cell sequencing data was performed and it was discovered that EC dysfunction plays an important role. Further pharmacological results showed that ZL capsule could alleviate fibrosis injury and collagen fiber deposition. The mechanism investigation results showed that the endothelial-to-mesenchymal transition (EndMT) and MHC class-II (MHC-II) expression in EC were improved. In addition, ZL capsule can attenuate the inflammatory response during MF by intervening the activation of CD4+T cell mediated by EC. For the first time, we provided evidence that ZL capsule could improve MF by alleviating EC dysfunction via the regulation of EndMT and expression of MHC-II. Taxonomy classification by evise: Myocardial fibrosis, Chinese Herbal Medicine, Traditional Medicine, Endothelium, dysfunction, Endothelial-to-mesenchymal transition.

Incidence of cancer for patients after bariatric surgery: evidence from 33 cohort studies.

BACKGROUND: With the rising prevalence of severe obesity, bariatric surgery has emerged as a crucial treatment option. As the number of surgeries performed worldwide increases, there has been growing interest in the impact of bariatric surgery on cancer incidence. While several studies have examined this relationship, the topic remains controversial. OBJECTIVES: We conducted this systematic review of cohort studies with meta-analysis to evaluate the effect of bariatric surgery versus nonsurgical treatment on overall cancer incidence. However, the effects may vary when focusing on specific cancer types, surgical procedures, or gender, so we conducted additional subgroup analyses. SETTING: A meta-analysis. University hospital. METHODS: The Cochrane, Embase, PubMed, and Web of Science databases were searched for studies from 1 January 2000 to 1 December 2022. Meta-analysis was conducted to evaluate the pooled effect and further implemented subgroup analysis stratified by cancer type, operation type, and sex. RESULTS: All cohort studies were included in this meta-analysis from 18,216 studies. The overall cancer incidence demonstrated a significant decrease in the group with bariatric surgery (odds ratios [OR] = .56, P = .000, 95% CI .46 to .68). In subgroup analysis, similar decrease effect was found in 9 cancers. Furthermore, the incidence of cancer decreased significantly in male (OR = .66, P = .001, 95% CI .51 to .85) and female patients (OR = .63, P = .000, 95% CI .57 to .69) and patients undergoing gastric bypass (OR = .46, P = .000, 95% CI .33 to .63) or sleeve gastrectomy (OR = .44, P = .001, 95% CI .27 to .70). CONCLUSIONS: In the overall analysis, bariatric surgery could reduce the incidence of cancer significantly. Further large-scale well-matched studies are needed to verify the protective effect of bariatric surgery on cancer incidence.

Solution-grown millimeter-scale Mn-doped CsPbBr3/Cs4PbBr6 crystals with enhanced photoluminescence and stability for light-emitting applications.

Metal halide perovskites are particularly emerging for optoelectronic applications in light-emitting diodes, photodetectors, and solar cells due to their flourishing photophysical properties. However, the poor stability of three-dimensional (3D) lead halide perovskite nanocrystals (NCs) significantly hampers their optoelectronics and photovoltaics applications. Embedding 3D perovskites into zero-dimensional (0D) perovskite crystals and doping ions of appropriate elements into host lattices provide effective approaches to improve the stability and optical-electronic performance. In this study, millimeter-scale Mn-doped and undoped CsPbBr3/Cs4PbBr6 perovskite crystals were successfully fabricated by a one-step slow cooling method. We systematically investigated the effects of Mn2+ ion doping on the PL performance and stability of CsPbBr3/Cs4PbBr6 crystals. Compared with undoped crystals, the existence of Mn2+ ions not only blue-shifted the PL peak but also improved the luminescence performance and stability of the prepared millimeter-sized crystals. Moreover, doping Mn2+ ions can increase the proportion of radiative recombination at low temperature, which may be because Mn2+ ions can effectively accelerate the decay of a dark exciton by the magnetic mixing of bright and dark excitons. In addition, green LED devices with high efficiency packaged as-grown crystals are explored, which promises further application in display backlights.

Insights into the Mechanism of Supramolecular Self-Assembly in the Astragalus membranaceus-Angelica sinensis Codecoction.

Astragalus membranaceus (Fisch.) Bge. (AM) and Angelica sinensis (Oliv.) Diels (AS) constitute a classic herb pair in prescriptions to treat myocardial fibrosis. To date, research on the AM-AS herb pair has mainly focused on the chemical compositions associated with therapeutic efficacy. However, supermolecules actually exist in herb codecoctions, and their self-assembly mechanism remains unclear. In this study, supermolecules originating from AM-AS codoping reactions (AA-NPs) were first reported. The chemical compositions of AA-NPs showed a dynamic self-assembly process. AA-NPs with different decoction times had similar surface groups and amorphous states; however, the size distributions of these nanoparticles might be different. Taking the interaction between Z-ligustilide and astragaloside IV as an example to understand the self-assembly mechanism of AA-NPs, it was found that the complex could be formed with a molar ratio of 2:1. Later, AA-NPs were proven to be effective in the treatment of myocardial fibrosis both in vivo and in vitro, the in-depth mechanisms of which were related to the recovery of cardiac function, reduced collagen deposition, and inhibition of the endothelial-to-mesenchymal transition that occurred in the process of myocardial fibrosis. Thus, AA-NPs may be the chemical material basis of the molecular mechanism of the AM-AS decoction in treating isoproterenol-induced myocardial fibrosis. Taken together, this work provides a supramolecular strategy for revealing the interaction between effective chemical components in herb-pair decoctions.

Rational Design of Bioorthogonally Activatable PROTAC for Tumor-Targeted Protein Degradation.

Protein degradation mediated by the proteolysis-targeting chimera (PROTAC) has emerged as an efficient strategy to accurately control intracellular protein levels. However, the development of PROTACs is limited by their systemic toxicity. Herein, we report a bioorthogonally activatable prodrug (BT-PROTAC) strategy to accurately control the activity of PROTACs. As a proof of concept, we introduced the highly reactive trans-cyclooctene into PROTAC molecule MZ1, the structure-acitivity relationships of which were well characterized previously, to construct the bioorthogonally activatable prodrug BT-PROTAC. Compared with MZ1, BT-PROTAC is incapable of degradation of BRD4 protein. However, BT-PROTAC can be activated by highly active tetrazine compound BODIPY-TZ in vitro. Furthermore, we could selectively degrade BRD4 protein in tumor tissue enabled by tumor-targeted tetrazine compound IR808-TZ. This strategy may represent an alternative to existing strategies and may be widely applied in the design of BT-PROTAC targeting other proteins.

Distance-Regulated Photoelectrochemical Sensor "Signal-On" and "Signal-Off" Transitions for the Multiplexed Detection of Viruses Exposed in the Aquatic Environment.

Photochemical (PEC) sensors were severely limited for multiplex detection applications due to the cross interference between multiplex signals at the single recognition interface. In this work, a distance-regulated PEC sensor was developed for multiplex detection by using an i-Motif sequence with conformational transformation activity as the signal transduction unit. Through dynamic regulation of the spatial distance between the end site of the functional sequence and the electrode material, the photogenerated electrons on the surface of the sensor were directionally transferred. Thus, a PEC sensor with "signal-on" and "signal-off" dual signal output modes was developed for simultaneous detection of multitarget molecules. Combining isothermal nucleic acid amplification, the PEC sensor constructed in this work was successfully applied to the detection of two virus (Norovirus and Rotavirus) nucleic acid sequences. Under the optimal condition, this bioassay protocol exhibits a linear range of 0.01-100 nM for both viruses with detection limits of 0.72 and 0.53 pM, respectively. In this study, a stimulus-mediated distance regulation strategy successfully addressed the transduction of multiplex detection signals at the single recognition interface of the PEC sensor. It is expected that the technical barriers to multiplex detection of PEC sensors will be overcome and the application of PEC sensing technology will be expanded in the field of environmental analysis.

Carbonized Platycladus orientalis Derived Carbon Dots Accelerate Hemostasis through Activation of Platelets and Coagulation Pathways.

Achieving rapid and effective hemostasis remains a multidisciplinary challenge. Here, distinctive functional carbon dots derived from carbonized Platycladus orientalis (CPO-CDs) are developed using one-step hydrothermal method. The negatively charged surface of CPO-CDs retains partial functional groups from CPO precursor, exhibiting excellent water solubility and high biocompatibility. Both rat liver injury model and tail amputation model have confirmed the rapid and effective hemostatic performance of CPO-CDs on exogenous hemorrhage. Further, on endogenous blood-heat hemorrhage syndrome rat model, CPO-CDs could inhibit hemorrhage and alleviate inflammation response. Interestingly, the excellent hemostasis performance of CPO-CDs is ascribed to activate exogenous coagulation pathway and common coagulation pathway. More importantly, metabolomics of rat plasma suggests that the hemostasis effect of CPO-CDs is closely related to platelet functions. Therefore, the designed in vitro experiments are performed and it is discovered that CPO-CDs significantly promote platelets adhesion, activation, and aggregation. Further, the underlying mechanism investigation suggests that Src/Syk signal pathway plays a key role in platelets activation triggered by CPO-CDs. Overall, CPO-CDs with rapid and excellent hemostatic performance are discovered for the first time, which could be an excellent candidate for the treatment of hemorrhagic diseases.

Association between circulating tumor cells in the peripheral blood and the prognosis of gastric cancer patients: a meta-analysis.

Background: Research on the correlation between circulating tumor cells (CTCs) and gastric cancer (GC) has increased rapidly in recent years. However, whether CTCs are associated with GC patient prognosis is highly controversial. Objective: This study aims to evaluate the value of CTCs to predict the prognosis of GC patients. Design: A meta-analysis. Data Sources and Methods: We searched the PubMed, Embase, and Cochrane Library databases for studies that reported the prognostic value of CTCs in GC patients before October 2022. The association between CTCs and overall survival (OS) and disease-free survival (DFS)/recurrence-free survival (RFS) and progression-free survival (PFS) of GC patients was assessed. Subgroup analyses were stratified by sampling times (pre-treatment and post-treatment), detection targets, detection method, treatment method, tumor stage, region, and HR (Hazard Ratio) extraction methods. Sensitivity analysis was performed by removing individual studies to assess the stability of the results. Publication bias was evaluated using funnel plots, Egger's test, and Begg's test. Results: We initially screened 2000 studies, of which 28 were available for further analysis, involving 2383 GC patients. The pooled analysis concluded that the detection of CTCs was associated with poor OS (HR = 1.933, 95% CI 1.657-2.256, p < 0.001), DFS/RFS (HR = 3.228, 95% CI 2.475-4.211, p < 0.001), and PFS (HR = 3.272, 95% CI 1.970-5.435, p < 0.001). Furthermore, the subgroup analysis stratified by tumor stage (p < 0.01), HR extraction methods (p < 0.001), detection targets (p < 0.001), detection method (p < 0.001), sampling times (p < 0.001), and treatment method (p < 0.001) all showed that CTC detection was associated with poor OS and DFS/RFS for GC patients. Furthermore, the study showed that CTCs were associated with the poor DFS/RFS of GC when CTCs were detected for patients from Asian or No-Asian regions (p < 0.05). In addition, higher CTCs predicted poorer OS for GC patients who are from Asian regions (p < 0.001), but without statistical difference for GC patients from No-Asian regions (p = 0.490). Conclusion: CTC detection in peripheral blood was associated with poor OS, DFS/RFS, and PFS in patients with GC.

Methods for Obtaining One Single Larmor Frequency, Either v1 or v2, in the Coherent Spin Dynamics of Colloidal Quantum Dots.

The coexistence of two spin components with different Larmor frequencies in colloidal CdSe and CdS quantum dots (QDs) leads to the entanglement of spin signals, complicating the analysis of dynamic processes and hampering practical applications. Here, we explored several methods, including varying the types of hole acceptors, air or anaerobic atmosphere and laser repetition rates, in order to facilitate the obtention of one single Larmor frequency in the coherent spin dynamics using time-resolved ellipticity spectroscopy at room temperature. In an air or nitrogen atmosphere, manipulating the photocharging processes by applying different types of hole acceptors, e.g., Li[Et3BH] and 1-octanethiol (OT), can lead to pure spin components with one single Larmor frequency. For as-grown QDs, low laser repetition rates favor the generation of the higher Larmor frequency spin component individually, while the lower Larmor frequency spin component can be enhanced by increasing the laser repetition rates. We hope that the explored methods can inspire further investigations of spin dynamics and related photophysical processes in colloidal nanostructures.

The 'double­track sign': A novel CT finding suggestive of the diagnosis of T1a gastric cancer.

Effective identification of T1a stage cancer is crucial for planning endoscopic resection for early gastric cancers. The present study aimed to determine the diagnostic value of the double-track sign in patients with T1a gastric cancer using computed tomography (CT) imaging. A total of 152 patients diagnosed with pathologically proven T1a gastric cancer at The First Affiliated Hospital of Zhengzhou University (Zhengzhou, China) between July 2011 and August 2021 were retrospectively reviewed. The control group consisted of 2,926 patients with gastritis. Clinical data, including patient characteristics and preoperative CT imaging findings with gastric morphological features, were reviewed and analyzed. Out of 51 patients with T1a gastric cancer finally included, 31 (60.8%) exhibited local double-track enhancement changes of the stomach, referred to as the 'double-track sign', on CT images. In addition, four patients (7.8%) had well-enhanced mucosal thickening of the gastric wall. Of the 2,926 control subjects, none had any double-track sign and six patients (0.2%) had local gastric wall thickening with abnormally strengthened enhancement. In conclusion, a double-track sign on CT images is beneficial in the diagnostic differentiation of T1a gastric cancer.

Preoperative prediction of vessel invasion in locally advanced gastric cancer based on computed tomography radiomics and machine learning.

Vessel invasion (VI) is an important factor affecting the prognosis of gastric cancer (GC), and the accurate determination of preoperative VI for locally advanced GC is of great clinical significance. Traditional methods for the evaluation of VI require postoperative pathological examination. Noninvasive preoperative evaluation of VI is therefore crucial to determine the best treatment strategy. To determine the value of preoperative prediction of gastric VI based on portal venous phase computed tomography (CT) radiomic features and machine-learning models, a retrospective analysis of 296 patients with locally advanced GC confirmed through pathological examination was performed. They were divided into two groups, VI+ (n=213) and VI- (n=83), based on pathological results. Using pyradiomics to extract two-dimensional radiomic features of the portal venous stage of locally advanced GC, data were divided into training (n=207) and validation sets (n=89), with a ratio of 7:3, and three feature selection methods were cascaded and merged. Finally, least absolute shrinkage and selection operator (LASSO) regression was used for feature screening to obtain the optimal feature subset. Four current representative machine-learning algorithms were used to construct the prediction model, the receiver operating characteristic curve was constructed to evaluate the predictive performance of the model, and the area under the curve (AUC), accuracy, sensitivity, and specificity were calculated. The differentiation degree, and the Lauren's and CA199 classifications were independent risk factors for locally advanced GC VI. Pyradiomics extracted 864 quantitative features of portal vein images of locally advanced GC. After filtering out low variance features using R, 236 features remained. Next, 18 features were screened using the LASSO algorithm. Extreme gradient boosting (XGBoost), logistic regression, Gaussian naive Bayes, and support vector machine models were constructed based on the 18 best features screened out of the portal venous CT images of advanced GC and three independent risk factors of GC VI in clinical features predicted the training set AUC values of 0.914, 0.897, 0.880, and 0.814, respectively. The predicted validation set AUC values were 0.870, 0.877, 0.859, and 0.773, respectively. The DeLong test results indicated no statistically significant difference in AUC values between the XGBoost and logistic regression models in the training and validation sets. The four machine-learning models showed high predictive performance. The logistic regression model had the highest AUC value in the validation set (0.877), and the accuracy and F1 score were 77 and 87.6%, respectively. CT radiomic features and machine-learning models based on the portal venous phase can be used as a noninvasive imaging method for the preoperative prediction of VI in locally advanced GC. The logistic regression model exhibited the highest diagnostic performance.