Abstract The issue of multimorbidity in children and adolescents is becoming increasingly prominent, but there is no consensus on the definition of multimorbidity. As research deepens, issues related to the comparability and standardization of relevant findings are gradually emerging. As a solution, a systematic review of both domestic and international research on multimorbidity is conducted, and a classification system for defining the concept of multimorbidity is proposed, offering more convenient conditions for the advancement of future research and cross study exchange.

Background::Pancreatic ductal adenocarcinoma (PDAC) is one of the main types of malignant tumor of the digestive system, and patient prognosis is affected by difficulties in early diagnosis, poor treatment response, and a high postoperative recurrence rate. Carbohydrate antigen 19-9 (CA19-9) has been widely used as a biomarker for the diagnosis and postoperative follow-up of PDAC patients. Nevertheless, the production mechanism and potential role of CA19-9 in PDAC progression have not yet been elucidated.Methods::We performed single-cell RNA sequencing on six samples pathologically diagnosed as PDAC (three CA19-9-positive and three CA19-9-negative PDAC samples) and two paracarcinoma samples. We also downloaded and integrated PDAC samples (each from three CA19-9-positive and CA19-9-negative patients) from an online database. The dynamics of the proportion and potential function of each cell type were verified through immunofluorescence. Moreover, we built an in vitro coculture cellular model to confirm the potential function of CA19-9. Results::Three subtypes of cancer cells with a high ability to produce CA19-9 were identified by the markers TOP2A, AQP5, and MUC5AC. CA19-9 production bypass was discovered on antigen-presenting cancer-associated fibroblasts (apCAFs). Importantly, the proportion of immature ficolin-1 positive (FCN1+) macrophages was high in the CA19-9-negative group, and the proportion of mature M2-like macrophages was high in the CA19-9-positive group. High proportions of these two macrophage subtypes were associated with an unfavourable clinical prognosis. Further experiments indicated that CA19-9 could facilitate the transformation of M0 macrophages into M2 macrophages in the tumor microenvironment. Conclusions::Our study described CA19-9 production at single-cell resolution and the dynamics of the immune atlas in CA19-9-positive and CA19-9-negative PDAC. CA19-9 could promote M2 polarization of macrophage in the pancreatic tumor microenvironment.

Pyroptosis is a programmed cell death mediated by cysteine proteases and is characterized by mitochondrial participation,inflammasome assembly,plasma membrane perforation,and inflammatory release.As an important mechanism mediating the body's inflammatory responses,pyroptosis plays a key role in renal ischemia-reperfusion injury(RIRI).This article reviews the molecular mechanisms of pyroptosis,pyroptotic mechanisms in RIRI,and the progress of research into therapeutic drugs in recent years,with the aim of providing a theoretical reference for the development of early treatments for RIRI.

Objectives:To investigate the clinical feasibility of three-dimensional(3D)high-resolution late gadolinium enhancement(LGE)MRI in accessing left atrial myocardial fibrosis in patients with atrial fibrillation(AF). Methods:A total of 34 AF patients referred for hybrid surgical ablation were retrospectively enrolled in this study.3D-LGE-MRI images were acquired by Siemens 3.0 T machine and analyzed by ADAS post-processing software by two experienced radiologists to obtain parameters such as the area and the area percentage of LGE.Regional analysis was performed by one of the two radiologists at ten left atrial segments.The Kappa test was used to assess the agreement for scoring image quality,and the interclass correlation coefficient(ICC)was used to evaluate the interobserver agreement of LGE parameters.The parameters of left atrial morphology,area(and area percentage)of LGE,and location of LGE were compared between patients with persistent AF and paroxysmal AF. Results:Images of all 34 patients were considered to have diagnostic value.The scores of the overall image quality and the clarity of the left atrial wall evaluated by two radiologists were(2.88±0.64)points and(3.26±0.75)points(radiologist 1),(2.97±0.58)points and(3.24±0.70)points(radiologist 2),respectively.The corresponding Kappa values were 0.724 and 0.859.Both the area and the area percentage of LGE showed good consistency among observers,and the ICCs were 0.969 and 0.950,respectively.The difference in the area of LGE and the area percentage of LGE between patients with paroxysmal and persistent atrial fibrillation was similar(both P＞0.05).Compared with patients with paroxysmal AF,patients with persistent AF had a higher Utah stage and more severe myocardial fibrosis in the right inferior pulmonary vein antrum and the left atrial septum(all P＜0.05). Conclusions:3D high-resolution LGE-MRI provides a non-invasive way to visualize and quantify left atrial myocardial fibrosis.The extent of left atrial fibrosis in patients with persistent AF is more severe than that in patients with paroxysmal AF,with a preferential distribution in the right inferior pulmonary vein antrum and the left atrial septum.

Objective To investigate the determinants of linezolid-associated neurological adverse reactions in patients with multidrug-resistant tuberculosis and develop a risk prediction model for such adverse events.Methods A prospective cohort study design was employed to select 120 patients with drug-resistant pulmonary tuberculosis who received a chemotherapy regimen containing linezolid at Guangzhou Chest Hospital from April 2023 to January 2024 as the study population.Clinical data,adverse reactions,and plasma concentration of linezolid were collected during fasting and at 2 hours post-medication.Univariate analysis and multivariate logistic regression were conducted to identify factors influencing linezolid-related neurological adverse reactions.Furthermore,a prediction model for such adverse reactions was developed,and its predictive efficacy and calibration ability were evaluated using ROC analysis.Results Re-treatment(OR=2.540,P=0.028),coexistence of cavities(OR=4.092,P=0.021),anemia(OR=10.921,P=0.005),and Cmin≥0.7665 mg/L(OR=6.813,P<0.001)are independent risk factors for the occurrence of linezolid-related neurological adverse reactions.The prediction model,based on these four factors,exhibits an AUC of 0.851(95%CI:0.774～0.929),accompanied by a Youden index of 0.590,a sensi-tivity of 66.7%,and a specificity of 92.3%.Moreover,the prediction model demonstrates excellent calibration ability.(Hosmer-lemeshow χ2=8.719,P=0.273).Conclusion In MDR/RR-TB patients,the presence of cavita-tion,retreatment,and anemia may confer a heightened risk of linezolid-related neurological adverse reactions.A risk prediction model incorporating these four indicators demonstrates significant predictive value for the occurrence of such adverse events.

ObjectTo explore the risk factors related to the intensity of post-stroke depression in patients with cerebral infarction during hospitalization in the rehabilitation department. MethodsThe hospital consultation records of cerebral infarction patients in Beijing Bo'ai Hospital from December, 2019 to February, 2023 were reviewed from the hospital information system, and those who were diagnosed as depression visited the department of psychology were selected. It was collected including general information of sexes, ages, education levels, matrimony; medical features of course, location, affected side, sensory disorders, aphasia, agrypnia, dysphagia, hand-shoulder syndrome, constipation; functioning of muscle strength and Brunnstrom stages; and scores of Mini-Mental State Examination (MMSE), National Institutes of Health Stroke Scale (NIHSS), Fugl-Meyer Assessment (FMA), Fugl-Meyer Assessment-Balance (FMA-B), modified Barthel Index (MBI) and Hamilton Depression Scale (HAMD). Patients with HAMD scores ≤ 20 were as the low group, and those > 20 were as the high group. ResultA total of 2 403 hospitalized stroke patients were included, out of which 269 patients with cerebral infarction were diagnosed as depression and visited the department of psychology; while 103 cases were in the low group and 166 cases were in the high group. The incidence of constipation was less, and the incidence of dysphagia and shoulder-hand syndrome was higher in the high group (χ² > 5.379, P < 0.05), with weaker strength of iliopsoas muscle and quadriceps muscle, earlier of Brunnstrom stage of lower extremities and hands, and worse scores of NIHSS, MMSE, FMA, FMA-B and MBI (|Z| > 2.020, t > 2.171, P < 0.05). Logistic regression showed that constipation (OR = 0.435), quadriceps muscle strength (OR = 0.782) and dysphagia (OR = 2.602) related to the intensity of post-stroke depression in convalescent patients (P < 0.05). ConclusionPost-stroke dysphagia and poor quadriceps muscle strength may exacerbate post-stroke depression; however, constipation may not.

Parkinson disease (PD) is a common chronic neurodegenerative disease that seriously affects the quality of life of patients and has become an important population health problem in society.The typical neuropathological feature of PD is the abnormal aggregation of α-synuclein (α-Syn) in the substantia nigra-striatal region, causing dopaminergic degenerative necrosis of neurons. With further research, it was found that cellular autophagy mediated the clearance process of pathological α-Syn involved in the pathogenesis of PD. Autophagy is an important pathway for cells to remove abnormal aggregated proteins and senescence-damaged organelles, and autophagic removal of abnormal α-Syn deposition can maintain cellular homeostasis and protect dopaminergic neurons. In addition, impaired autophagy causes α-Syn aggregation, increases α-Syn propagation in the brain, promotes the degeneration of dopaminergic neurons, and is involved in the development of PD.PD-related genes affect autophagy regulation, and mutations in related genes can lead to impaired lysosomal function to block autophagy. At the same time, abnormal aggregation of α-Syn further disrupts the autophagy process, reduces the autophagic clearance capacity, and increases the accumulation of neurotoxicity. Impaired autophagy and abnormal α-Syn aggregation are important mechanisms of degeneration in nigrostriatal dopaminergic neurons. Therefore, studies targeting autophagy and abnormal α-Syn aggregation may provide new ideas for the pathogenesis of PD, and reducing α-Syn accumulation by increasing autophagic flux may become a key target for the treatment of PD.

Objective Based on the process theory of stress effect,the structural equation model of the influencing factors of self-regulatory fatigue in maintenance hemodialysis patients is constructed,which provides theoretical bases and references for the formulation of intervention programs to relieve self-regulatory fatigue in patients.Method A total of 420 maintenance hemodialysis patients were surveyed using General Information Questionnaire,Self-Regulatory Fatigue Scale,Dialysis Symptom Index,Life Orientation Test-Revised,Perceived Social Support Scale,Brief Illness Perception Questionnaire and Medical Coping Styles Questionnaire.Results Total score of self-regulatory fatigue in maintenance hemodialysis patients was(49.52±10.93),and self-regulatory fatigue showed significant positive correlation with symptom distress,the illness perception,avoidance coping style,yieldly coping(r=0.476,0.428,0.303,0.611,all P＜0.01);self-regulatory fatigue showed significant negative correlation with perceived social support and dispositional optimism(r=-0.410,-0.652,all P＜0.01);it showed no significant correlation with facing coping(r=-0.032,P＞0.05).The Bootstrap analysis revealed that the mediation effect of yielding coping,dispositional optimism,perceived social support,and illness perception between symptom distress and self-regulatory fatigue was significant(95％CI:0.027～0.203).The overall effect of symptom distress on self-regulatory fatigue was(P＜0.001,95％CI:0.576～0.751);the direct effect was(P＜0.001,95％CI:0.170～0.357);the indirect effect was(P＜0.001,95％CI:0.332～0.485);the mediation effect accounted for 61.1％of the total effect value.Conclusion Maintenance hemodialysis patients have a high degree of self-regulatory fatigue,which needs to be further improved.Medical staff should timely identify and evaluate the symptom distress of patients,focus on guiding patients to adjust optimistic disease,provide patients with psychological guidance and stress coping strategies,reduce the negative coping behavior tendency,guide the patients correctly perceive support and care in social relations,help patients set up the correct disease cognition,thus reducing the patient's self-regulatory fatigue.

【Objective】 To investigate the molecular mechanism of microRNA-101-5p (miR-101-5p) affecting the proliferation and invasion of lung squamous cell carcinoma (LUSC) cells. 【Methods】 We downloaded the miRNA mature expression data and total RNA sequencing data of TCGA-LUSC from TCGA database to identify differentially expressed genes. The signal pathway enriched in ATAD2 was analyzed. The mRNA expressions of miR-101-5p and ATAD2 in the LUSC cells were detected by qRT-PCR. The effects of miR-101-5p on the proliferation and invasion of LUSC cells were detected by MTT assay, cloning assay, and invasion assay. The effects of ATAD2 on the cell cycle of LUSC cells were detected by flow cytometry. Western blotting was used to detect the expression of ATAD2 protein. Double luciferase experiment was used to verify whether miR-101-5p could bind to ATAD2 target. Finally, we detected the changes in the proliferation, cloning and invasion ability of LUSC cells by co-transfection with oe-ATAD2 and miR-101-5p mimic, and further explored whether miR-101-5p could regulate the biological function of LUSC cells through ATAD2. 【Results】 The miR-101-5p was significantly downregulated in LUSC tissues and cells. Overexpression of miR-101-5p could significantly inhibit the proliferation and invasion of LUSC cells. ATAD2, its downstream regulatory target gene, was significantly upregulated in LUSC, and miR-101-5p and ATAD2 expressions were inversely correlated. GSEA enrichment results showed that ATAD2 was significantly enriched in the cell cycle signal pathway. The double luciferase experiment proved that miR-101-5p targeted ATAD2, and the recovery experiment showed that miR-101-5p regulated the proliferation and invasion of LUSC cells by targeting ATAD2. 【Conclusion】 In this study, we found that miR-101-5p had low expression in LUSC, and that miR-101-5p decreased the proliferation and invasion of LUSC cells by targeted inhibition of ATAD2.

Randomized controlled trial (RCT) are considered the "gold standard" for evaluating the causal effects of interventions on outcome measures. However, due to high research costs and ethical constraints, conducting RCT in clinical practice, especially in the surgical field, faces numerous challenges such as difficulties in subject recruitment, implementation of blinding, and standardization of interventions. In such cases, using real-world data to perform causal inference under the framework of target trial emulation (TTE), based on the principles of RCT design, helps to identify and reduce biases arising from design flaws in traditional observational studies, such as immortal time bias, confounding, selection bias, or collider bias. This approach can produce high-quality evidence comparable to that of RCT, thereby enhancing the clinical guidance value of real-world data studies. However, TTE has limitations, such as the inability to completely eliminate confounding, high quality requirements for source data, and the current lack of reporting standards. Therefore, researchers should be fully aware of these limitations to avoid making incorrect causal inferences. This article intends to provide an overview of the TTE framework, implementation points, application scope, application cases, and advantages and disadvantages of the framework.