Interfacial Mass Diagnostics: Quantitative Perspective on Construction and Mechanism Understanding of Dye-Sensitized, Perovskite and Quantum Dots Solar Cells.

Dye-sensitized solar cells (DSSCs), quantum dot-sensitized solar cells (QDSSCs) and perovskite solar cells (PSCs) have attracted wide attention. DSSCs, QDSSCs and PSCs can be prepared by liquid phase or solid phase, which causes a certain range of interface micro-mass changes during preparation. In addition, the photoelectric conversion process occurring inside the device also inevitably causes interface micro-mass changes. Interpretation of these interface micro-mass changes can help to optimize the cell structure, improve the stability and performance repeatability of the device, as well as directly or indirectly infer, track and predict the internal photoelectric conversion mechanism of the device. Quartz crystal microbalance (QCM) is a powerful tool for studying surface mass changes, extending this technology to the fields of solar cells to directly obtain interface micro mass changes, which makes the research more in-depth and opens up a new perspective for explaining the basic principles of solar cells. This review summarizes the research progress of QCM application in DSSCs, QDSSCs and PSCs in recent years, and explores the challenges and new opportunities of QCM application in new solar cells in the future.

External validation of predictive models for new vertebral fractures following percutaneous vertebroplasty.

OBJECTIVE: To investigate the external validation and scalability of four predictive models regarding new vertebral fractures following percutaneous vertebroplasty. METHODS: Utilizing retrospective data acquired from two centers, compute the area under the curve (AUC), calibration curve, and Kaplan-Meier plot to assess the model's discrimination and calibration. RESULTS: In the external validation of Zhong et al.'s 2015 predictive model for the probability of new fractures post-vertebroplasty, the AUC for re-fracture at 1, 2, and 3 years postoperatively was 0.570, 0.617, and 0.664, respectively. The AUC for Zhong et al.'s 2016 predictive model for the probability of new fractures in neighboring vertebrae was 0.738. Kaplan-Meier plot results for both models indicated a significantly lower incidence of re-fracture in low-risk patients compared to high-risk patients. Li et al.'s 2021 model had an AUC of 0.518, and its calibration curve suggested an overestimation of the probability of new fractures. Li et al.'s 2022 model had an AUC of 0.556, and its calibration curve suggested an underestimation of the probability of new fractures. CONCLUSION: The external validation of four models demonstrated that the predictive model proposed by Zhong et al. in 2016 exhibited superior external generalization capabilities.

Tertiary lymphoid structures as a potential prognostic biomarker for combined hepatocellular-cholangiocarcinoma.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA), as a rare primary hepatic tumor, is challenging to accurately assess in terms of the clinical outcomes and prognostic risk factors in patients. This study aimed to clarify the function of tertiary lymphoid structure (TLS) status in predicting the outcome of cHCC-CCA and to preliminarily explore the possible mechanism of TLS formation. METHODS: The TLSs, with different spatial distributions and densities, of 137 cHCC-CCA were quantified, and their association with prognosis was assessed by Cox regression and Kaplan-Meier analyses. We further validated TLS possible efficacy in predicting immunotherapy responsiveness in two cHCC-CCA case reports. TLS composition and its relationship to CXCL12 expression were analysed by fluorescent multiplex immunohistochemistry. RESULTS: A high intratumoural TLS score was correlated with prolonged survival, whereas a high TLS density in adjacent tissue indicated a worse prognosis in cHCC-CCA. Mature TLSs were related to favorable outcomes and showed more CD8 + T cells infiltrating tumor tissues. We further divided the cHCC-CCA patients into four immune grades by combining the peri-TLS and intra-TLS, and these grades were an independent prognostic factor. In addition, our reported cases suggested a potential value of TLS in predicting immunotherapy response in cHCC-CCA patients. Our findings suggested that CXCL12 expression in cHCC-CCA tissue was significantly correlated with TLS presence. CONCLUSION: The spatial distribution and density of TLSs revealing the characteristics of the cHCC-CCA immune microenvironment, significantly correlated with prognosis and provided a potential immunotherapy response biomarker for cHCC-CCA.

CDKN2A inhibited ferroptosis through activating JAK2/STAT3 pathway to modulate cisplatin resistance in cervical squamous cell carcinoma.

Cervical squamous cell carcinoma (CESC) is a significant threat to women's health. Resistance to cisplatin (DDP), a common treatment, hinders the therapeutic efficacy. Understanding the molecular basis of DDP resistance in CESC is imperative. Cyclin-dependent kinase inhibitor 2A (CDKN2A) expression was evaluated through quantitative real-time-PCR and western blot in clinical samples from 30 CESC patients and human cervical epithelial cells and CESC cell lines (SiHa, C33A, and Caski). It was also evaluated through bioinformatics analysis in Timer, Ualcan, and GEPIA database. Cell viability was detected by CCK-8. Apoptosis was detected by Calcein AM/PI assay. Lipid reactive oxygen species (ROS), malondialdehyde, glutathione, Fe2+, and iron level were detected by kits. Protein level of JAK2, STAT3, p-JAK2, p-STAT3, ACSL4, GPX4, SLC7A11, and FTL were detected by western blot. In CESC, elevated CDKN2A expression was observed. Cisplatin exhibited a dual effect, inhibiting cell proliferation and inducing ferroptosis in CESC. CDKN2A knockdown in a cisplatin-resistant cell line suppressed proliferation and induced ferroptosis. Moreover, CDKN2A was identified as an inhibitor of erastin-induced ferroptosis. Additionally, targeting the JAK2/STAT3 pathway enhanced ferroptosis in cisplatin-resistant cells. CDKN2A could inhibit ferroptosis in CESC through activating JAK2/STAT3 pathway to modulate cisplatin resistance.

The Endometrial Stem/Progenitor Cells and Their Niches.

Endometrial stem/progenitor cells are a type of stem cells with the ability to self-renew and differentiate into multiple cell types. They exist in the endometrium and form niches with their neighbor cells and extracellular matrix. The interaction between endometrial stem/progenitor cells and niches plays an important role in maintaining, repairing, and regenerating the endometrial structure and function. This review will discuss the characteristics and functions of endometrial stem/progenitor cells and their niches, the mechanisms of their interaction, and their roles in endometrial regeneration and diseases. Finally, the prospects for their applications will also be explored.

Study on the Effect of Electrolytes on Processing Efficiency and Accuracy of Titanium Alloy Utilizing Laser and Shaped Tube Electrochemical Machining.

Electrochemical machining (ECM) has become more prevalent in titanium alloy processing. However, the presence of the passivation layer on the titanium alloys significantly impacts the performance of ECM. In an attempt to overcome the passivation effects, a high-temperature electrolyte or the addition of halogen ions to the electrolyte has been used. Still, it often results in compromised machining accuracy and surface roughness. This study applied laser and shaped tube electrolytic machining (Laser-STEM) for titanium alloy drilling, where the laser was guided to the machining zone via total internal reflection. The performance of Laser-STEM using different types of electrolytes was compared. Further, the effects of laser power and pulse voltage on the machining side gap, material removal rate (MRR), and surface roughness were experimentally studied while drilling small holes in titanium alloy. The results indicated that the use of passivating electrolytes improved the machining precision, while the MRR decreased with an increase in laser power during Laser-STEM. The MRR showed an increase while using aggressive electrolytes; however, at the same time, the machining precision deteriorated with the increase in laser power. Particularly, the maximum feeding rate of 6.0 mm/min for the tool electrode was achieved using NaCl solution as the electrolyte during Laser-STEM, marking a 100% increase compared to the rate without the use of a laser. Moreover, the model and equivalent circuits were also established to illustrate the material removal mechanisms of Laser-STEM in different electrolytes. Lastly, the processing of deep small holes with a diameter of 1.5 mm, a depth of 38 mm, and a surface roughness of Ra 2 µm was achieved via Laser-STEM without the presence of a recast layer and heat-affected zones. In addition, the cross-inner flow channels in the titanium alloys were effectively processed.

Inherited KDM6AA649T facilitates tumor-immune escape and exacerbates colorectal signet-ring cell carcinoma outcomes.

Childhood onset of colorectal signet-ring cell carcinoma (CR-SRCC) is extremely rare and featured as highly malignant with poor prognosis. Here we reported a CR-SRCC case of 11-year-old boy with a novel inherited X-linked KDM6AA694T mutation. The H3K27me3 demethylase KDM6A was frequently mutated in varieties of tumors and acts as a tumor suppressor. In vivo H3K27me3 demethylation assay demonstrated that KDM6AA694T had dampened H3K27me3 demethylase activity. Overexpression of KDM6AA694T in SRCC cell line KATO3 promoted cell proliferation, invasion and migration, which were further confirmed in vivo by constructing orthotopic tumor growth and lung metastasis model. Besides, expression of KDM6AA694T in immune cells suppresses inflammatory macrophage response and effector T cell response. In conclusion, we characterized a novel inherited KDM6AA694T mutant from a childhood-onset SRCC case and demonstrated that the mutant with impaired H3K27me3 demethylase activity could potentiate tumor malignancy and suppress antitumor immunity.

A novel tumor mutation-related long non-coding RNA signature for predicting overall survival and immunotherapy response in lung adenocarcinoma.

Background: Immunotherapy has changed the treatment landscape for lung cancer. This study aims to construct a tumor mutation-related model that combines long non-coding RNA (lncRNA) expression levels and tumor mutation levels in tumor genomes to detect the possibilities of the lncRNA signature as an indicator for predicting the prognosis and response to immunotherapy in lung adenocarcinoma (LUAD). Methods: We downloaded the tumor mutation profiles and RNA-seq expression database of LUAD from The Cancer Genome Atlas (TCGA). Differentially expressed lncRNAs were extracted based on the cumulative number of mutations. Cox regression analyses were used to identify the prognostic lncRNA signature, and the prognostic value of the five selected lncRNAs was validated by using survival analysis and the receiver operating characteristic (ROC) curve. We used qPCR to validate the expression of five selected lncRNAs between human lung epithelial and human lung adenocarcinoma cell lines. The ImmuCellAI, immunophenoscore (IPS) scores and Tumor Immune Dysfunction and Exclusion (TIDE) analyses were used to predict the response to immunotherapy for this mutation related lncRNA signature. Results: A total of 162 lncRNAs were detected among the differentially expressed lncRNAs between the Tumor mutational burden (TMB)-high group and the TMB-low group. Then, five lncRNAs (PLAC4, LINC01116, LINC02163, MIR223HG, FAM83A-AS1) were identified as tumor mutation-related candidates for constructing the prognostic prediction model. Kaplan‒Meier curves showed that the overall survival of the low-risk group was significantly better than that of the high-risk group, and the results of the GSE50081 set were consistent. The expression levels of PD1, PD-L1 and CTLA4 in the low-risk group were higher than those in the high-risk group. The IPS scores and TIDE scores of patients in the low-risk group were significantly higher than those in the high-risk group. Conclusion: Our findings demonstrated that the five lncRNAs (PLAC4, LINC01116, LINC02163, MIR223HG, FAM83A-AS1) were identified as candidates for constructing the tumor mutation-related model which may serve as an indicator of tumor mutation levels and have important implications for predicting the response to immunotherapy in LUAD.

Transient cavity-cavity strong coupling at terahertz frequency on LiNbO3 chips.

Terahertz (THz) microcavities have garnered considerable attention for their ability to localize and confine THz waves, allowing for strong coupling to remarkably enhance the light-matter interaction. These properties hold great promise for advancing THz science and technology, particularly for high-speed integrated THz chips where transient interaction between THz waves and matter is critical. However, experimental study of these transient time-domain processes requires high temporal and spatial resolution since these processes, such as THz strong coupling, occur in several picoseconds and microns. Thus, most literature studies rarely cover temporal and spatial processes at the same time. In this work, we thoroughly investigate the transient cavity-cavity strong-coupling phenomena at THz frequency and find a Rabi-like oscillation in the microcavities, manifested by direct observation of a periodic energy exchange process via a phase-contrast time-resolved imaging system. Our explanation, based on the Jaynes-Cummings model, provides theoretical insight into this transient strong-coupling process. This work provides an opportunity to deeply understand the transient strong-coupling process between THz microcavities, which sheds light on the potential of THz microcavities for high-speed THz sensor and THz chip design.

Deep partially linear cox model for current status data.

Deep learning has continuously attained huge success in diverse fields, while its application to survival data analysis remains limited and deserves further exploration. For the analysis of current status data, a deep partially linear Cox model is proposed to circumvent the curse of dimensionality. Modeling flexibility is attained by using deep neural networks (DNNs) to accommodate nonlinear covariate effects and monotone splines to approximate the baseline cumulative hazard function. We establish the convergence rate of the proposed maximum likelihood estimators. Moreover, we derive that the finite-dimensional estimator for treatment covariate effects is $\sqrt{n}$-consistent, asymptotically normal, and attains semiparametric efficiency. Finally, we demonstrate the performance of our procedures through extensive simulation studies and application to real-world data on news popularity.

POLE2 promotes osteosarcoma progression by enhancing the stability of CD44.

Osteosarcoma (OS) is the most prevalent primary malignancy of bone in children and adolescents. It is extremely urgent to develop a new therapy for OS. In this study, the GSE14359 chip from the GEO database was used to screen differentially expressed genes in OS. DNA polymerase epsilon 2 (POLE2) was confirmed to overexpress in OS tissues and cell lines by immunohistochemical staining, qPCR and Western blot. Knockdown of POLE2 inhibited the proliferation and migration of OS cells in vitro, as well as the growth of tumors in vivo, while the apoptosis rate was increased. Bioinformatics analysis revealed that CD44 and Rac signaling pathway were the downstream molecule and pathway of POLE2, which were inhibited by knockdown of POLE2. POLE2 reduced the ubiquitination degradation of CD44 by acting on MDM2. Moreover, knockdown of CD44 inhibited the tumor-promoting effects of POLE2 overexpression on OS cells. In conclusion, POLE2 augmented the expression of CD44 via inhibiting MDM2-mediated ubiquitination, and then activated Rac signaling pathway to influence the progression of OS, indicating that POLE2/CD44 might be potential targets for OS treatment.

4-Fluorobenzyl cyanide, a sterically-hindered solvent expediting interfacial kinetics in lithium-ion batteries.

The electrochemical performance of lithium-ion batteries (LIBs) is plagued by sluggish interfacial kinetics. Fortunately, the Li+ solvation structure bridges the bulk electrolyte and interfacial chemistry, providing a pathway for promoting electrochemical kinetics in LIBs. Herein, we improve the interfacial kinetics by tuning the Li+ coordination chemistry based on solvent molecular engineering. Specifically, 4-fluorobenzyl cyanide (FBCN), featuring steric hindrance and a weak Lewis basic center, is designed to construct a bulky coordination structure with Li+, weakening ion-dipole interaction (Li+-solvents) but promoting coulombic attraction (Li+-anions) at a normal Li salt concentration. This sterically-controlled solvation chemistry reduces the interfacial barrier and thus contributes to improved rate performance, as demonstrated practically in LiFePO4//graphite pouch cells. This study provides fresh insights into solvent steric control and coordination chemistry engineering, opening a new avenue for enhancing electrochemical kinetics in LIBs.

Single-cell insights: pioneering an integrated atlas of chromatin accessibility and transcriptomic landscapes in diabetic cardiomyopathy.

BACKGROUND: Diabetic cardiomyopathy (DCM) poses a growing health threat, elevating heart failure risk in diabetic individuals. Understanding DCM is crucial, with fibroblasts and endothelial cells playing pivotal roles in driving myocardial fibrosis and contributing to cardiac dysfunction. Advances in Multimodal single-cell profiling, such as scRNA-seq and scATAC-seq, provide deeper insights into DCM's unique cell states and molecular landscape for targeted therapeutic interventions. METHODS: Single-cell RNA and ATAC data from 10x Multiome libraries were processed using Cell Ranger ARC v2.0.1. Gene expression and ATAC data underwent Seurat and Signac filtration. Differential gene expression and accessible chromatin regions were identified. Transcription factor activity was estimated with chromVAR, and Cis-coaccessibility networks were calculated using Cicero. Coaccessibility connections were compared to the GeneHancer database. Gene Ontology analysis, biological process scoring, cell-cell communication analysis, and gene-motif correlation was performed to reveal intricate molecular changes. Immunofluorescent staining utilized various antibodies on paraffin-embedded tissues to verify the findings. RESULTS: This study integrated scRNA-seq and scATAC-seq data obtained from hearts of WT and DCM mice, elucidating molecular changes at the single-cell level throughout the diabetic cardiomyopathy progression. Robust and accurate clustering analysis of the integrated data revealed altered cell proportions, showcasing decreased endothelial cells and macrophages, coupled with increased fibroblasts and myocardial cells in the DCM group, indicating enhanced fibrosis and endothelial damage. Chromatin accessibility analysis unveiled unique patterns in cell types, with heightened transcriptional activity in myocardial cells. Subpopulation analysis highlighted distinct changes in cardiomyocytes and fibroblasts, emphasizing pathways related to fatty acid metabolism and cardiac contraction. Fibroblast-centered communication analysis identified interactions with endothelial cells, implicating VEGF receptors. Endothelial cell subpopulations exhibited altered gene expressions, emphasizing contraction and growth-related pathways. Candidate regulators, including Tcf21, Arnt, Stat5a, and Stat5b, were identified, suggesting their pivotal roles in DCM development. Immunofluorescence staining validated marker genes of cell subpopulations, confirming PDK4, PPARγ and Tpm1 as markers for metabolic pattern-altered cardiomyocytes, activated fibroblasts and endothelial cells with compromised proliferation. CONCLUSION: Our integrated scRNA-seq and scATAC-seq analysis unveils intricate cell states and molecular alterations in diabetic cardiomyopathy. Identified cell type-specific changes, transcription factors, and marker genes offer valuable insights. The study sheds light on potential therapeutic targets for DCM.

Integrated Bioinformatics and Machine Learning Analysis Identify ACADL as a Potent Biomarker of Reactive Mesothelial Cells.

Mesothelial cells with reactive hyperplasia are difficult to distinguish from malignant mesothelioma cells on cell morphology. This study aimed to identify and validate potential biomarkers that distinguish mesothelial cells from mesothelioma cells through machine learning combined with immunohistochemistry experiments. This study integrated the gene expression matrix from three Gene Expression Omnibus data sets (GSE2549, GSE12345, and GSE51024) to analyze the differently expressed genes between normal and mesothelioma tissues. Then, three machine learning algorithms, least absolute shrinkage and selection operator, support vector machine-recursive feature elimination, and random forest were used to screen and obtain four shared candidate markers, including ACADL, EMP2, GPD1L, and HMMR. The receiver operating characteristic curve analysis showed that the area under the curve for distinguishing normal from mesothelioma was 0.976, 0.943, 0.962, and 0.956, respectively. The expression and diagnostic performance of these candidate genes were validated in another two independent data sets (GSE42977 and GSE112154), indicating that the performances of ACADL, GPD1L, and HMMR were consistent between the training and validation data sets. Finally, the optimal candidate marker ACADL was verified by immunohistochemistry assay. ACADL was stained strongly in mesothelial cells, especially for reactive hyperplasic mesothelial cells, but was negative in malignant mesothelioma cells. Therefore, ACADL has the potential to be used as a specific marker of reactive hyperplasic mesothelial cells in the differential diagnosis of mesothelioma.

Exploring the biological roles of DHX36, a DNA/RNA G-quadruplex helicase, highlights functions in male infertility: A comprehensive review.

It is estimated that 15 % of couples at reproductive age worldwide suffer from infertility, approximately 50 % of cases are caused by male factors. Significant progress has been made in the diagnosis and treatment of male infertility through assisted reproductive technology and molecular genetics methods. However, there is still inadequate research on the underlying mechanisms of gene regulation in the process of spermatogenesis. Guanine-quadruplexes (G4s) are a class of non-canonical secondary structures of nucleic acid commonly found in genomes and RNAs that play important roles in various biological processes. Interestingly, the DEAH-box helicase 36 (DHX36) displays high specificity for the G4s which can unwind both DNA G4s and RNA G4s enzymatically and is highly expressed in testis, thereby regulating multiple cellular functions including transcription, pre-mRNA splicing, translation, telomere maintenance, genomic stability, and RNA metabolism in development and male infertility. This review provides an overview of the roles of G4s and DHX36 in reproduction and development. We mainly focus on the potential role of DHX36 in male infertility. We also discuss possible future research directions regarding the mechanism of spermatogenesis mediated by DHX36 through G4s in spermatogenesis-related genes and provide new targets for gene therapy of male infertility.

Cloning of CAT genes in Satsuma mandarin and their expression characteristics in response to environmental stress and arbuscular mycorrhizal fungi.

KEY MESSAGE: CitCAT1 and CitCAT2 were cloned and highly expressed in mature leaves. High temperatures up-regulated CitCAT1 expression, while low temperatures and Diversispora versiformis up-regulated CitCAT2 expression, maintaining a low oxidative damage. Catalase (CAT), a tetrameric heme-containing enzyme, removes hydrogen peroxide (H2O2) to maintain low oxidative damage in plants exposed to environmental stress. This study aimed to clone CAT genes from Citrus sinensis cv. "Oita 4" and analyze their expression patterns in response to environmental stress, exogenous abscisic acid (ABA), and arbuscular mycorrhizal fungal inoculation. Two CAT genes, CitCAT1 (NCBI accession: PP067858) and CitCAT2 (NCBI accession: PP061394) were cloned, and the open reading frames of their proteins were 1479 bp and 1539 bp, respectively, each encoding 492 and 512 amino acids predicted to be localized in the peroxisome, with CitCAT1 being a stable hydrophilic protein and CitCAT2 being an unstable hydrophilic protein. The similarity of their amino acid sequences reached 83.24%, and the two genes were distantly related. Both genes were expressed in stems, leaves, flowers, and fruits, accompanied by the highest expression in mature leaves. In addition, CitCAT1 expression was mainly up-regulated by high temperatures (37 °C), exogenous ABA, and PEG stress within a short period of time, whereas CitCAT2 expression was up-regulated by exogenous ABA and low-temperature (4 °C) stress. Low temperatures (0 °C) for 12 h just up-regulated CitCAT2 expression in Diversispora versiformis-inoculated plants, and D. versiformis inoculation up-regulated CitCAT2 expression, along with lower hydrogen peroxide and malondialdehyde levels in mycorrhizal plants at low temperatures. It is concluded that CitCAT2 has an important role in resistance to low temperatures as well as mycorrhizal enhancement of host resistance to low temperatures.

Exploiting the potential of a novel "in-situ latent heat recovery" in hollow-fiber vacuum membrane distillation process for simultaneously improved water production and energy efficiency.

Thermal driven membrane distillation (MD) technology is a promising method for purifying & recovering various salty (especially high salty) or contaminated wastewaters with low-grade heat sources. However, the drawbacks of "high energy consumption" and "high cooling water consumption" pose special challenges for the future development of this technology. In this article, we report an innovative strategy called "in-situ heat transfer", which is based on the jacketed structure composed of hollow fiber membranes and capillary heat exchange tubes, to simplify the migration steps of condensation latent heat in MD heat recovery process. The results indicate that the novel heat recovery strategy exhibits higher growth rates both in the flux and gained output ratio (47.4 % and 173.1 %, respectively), and further reduces the system's dependence on cooling water. In sum, under the control of the "in-situ heat transfer" mechanism, the functional coupling of "vapor condensation (exothermic)" and "feed evaporation (endothermic)" in limited-domain space is an attractive alternative solution, because it eliminates the disadvantages of the imbalance between heat supply and demand in traditional heat recovery methods. Our research may facilitate the development of MD heat recovery modules for industrial applications, which will help to further achieve the goal of energy saving and emission reduction.

Validation of numerical simulations and experiments on impulse characteristics induced by self-excited oscillation.

The high-frequency pulse flow, equivalent to the natural frequency of rocks, is generated by a self-excited oscillating cavity to achieve resonance rock-breaking. The flow field and oscillating mechanism of the self-excited oscillating cavity were simulated using the large eddy simulation method of Computational Fluid Dynamics (CFD). A field-scale testing apparatus was developed to investigate the impulse characteristics and verify the simulation results. The results show that the fluid at the outlet at the tool is deflected due to the pulse oscillation of the fluid. The size and shape of low-pressure vortices constantly change, leading to periodic changes in fluid impedance within the oscillating cavity. The impulse frequency reaches its highest point when the length-diameter ratio is 0.67. As the length-diameter ratio increases, the tool pressure loss also increases. Regarding the cavity thickness, the impulse frequency of the oscillating cavity initially decreases, then increases, and finally decreases again. Moreover, both the impulse frequency and pressure loss increase with an increase in displacement. The numerical simulation findings align with the experimental results, thus confirming the validity of the theoretical model. This research provides theoretical guidance for the practical application of resonance rock-breaking technology.

Timing of first abdominal operation in Crohn's disease based on a diagnostic model.

This study aims to develop a clinical diagnostic model for assessing the need for initial abdominal surgery in patients diagnosed with Crohn's disease (CD) and create a nomogram to facilitate clinical decision-making. A total of 164 surgical CD patients and 230 control CD patients were included in this retrospective analysis. Least Absolute Shrinkage and Selection Operator (Lasso) regression and binomial logistic regression were employed to select clinical variables. The 394 CD patients were randomly allocated to a training set and a validation set in a 7:3 ratio. The filtered variables were used to establish a diagnostic model and nomogram in the training set, subsequently validated in the testing set. Decision Curve Analysis (DCA) and clinical impact curve were constructed to validate the clinical applicability of the model. Binomial logistic regression analysis identified seven clinical variables with a p-value less than 0.01, including Biomarker (B), Waist-to-Height Ratio (WHtR), Intestinal obstruction, Albumin (ALB), Crohn's Disease Activity Index (CDAI), Myocardial Flow Index (MFI), and C-reactive protein (CRP). These variables were utilized to establish the diagnostic model. Calibration curves showed good alignment, with a C-index of 0.996 in the training set and 0.990 in the testing set. DCA and clinical impact curve demonstrated that the diagnostic model had good clinical efficiency and could provide clinical benefits. A validated diagnostic model for determining the timing of the first abdominal operation in CD patients was established and evaluated, showing high discriminative ability, calibration, and clinical efficiency. It can be utilized by clinicians to assess the optimal timing for transitioning CD patients from medical treatment to surgical intervention, providing valuable references for individualized treatment decisions for CD patients.