Automatic ultrasensitive lateral flow immunoassay based on a color-enhanced signal amplification strategy.

Lateral flow immunoassays (LFIAs) are an essential and widely used point-of-care test for medical diagnoses. However, commercial LFIAs still have low sensitivity and specificity. Therefore, we developed an automatic ultrasensitive dual-color enhanced LFIA (DCE-LFIA) by applying an enzyme-induced tyramide signal amplification method to a double-antibody sandwich LFIA for antigen detection. The DCE-LFIA first specifically captured horseradish peroxidase (HRP)-labeled colored microspheres at the Test line, and then deposited a large amount of tyramide-modified signals under the catalytic action of HRP to achieve the color superposition. A limit of detection (LOD) of 3.9 pg/mL and a naked-eye cut-off limit of 7.8 pg/mL were achieved for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleoprotein. Additionally, in the inactivated virus detections, LOD equivalent to chemiluminescence (0.018 TCID50/mL) was obtained, and it had excellent specificity under the interference of other respiratory viruses. High sensitivity has also been achieved for detection of influenza A, influenza B, cardiac troponin I, and human chorionic gonadotrophin using this DCE-LFIA, suggesting the assay is universally applicable. To ensure the convenience and stability in practical applications, we created an automatic device. It provides a new practical option for point-of-care test immunoassays, especially ultra trace detection and at-home testing.

The predictive value of conventional magnetic resonance imaging combined with intravoxel incoherent motion parameters for evaluating maternal and neonatal clinical outcomes in patients with placenta accreta spectrum disorders.

INTRODUCTION: We aimed to identify factors predictive of adverse maternal and neonatal outcomes in patients with placenta accreta spectrum (PAS) disorders using magnetic resonance imaging (MRI) and intravoxel incoherent motion (IVIM) parameters. METHOD: Fifty-six normal singleton pregnancies at 33-39 weeks of gestation underwent MRI examination at 1.5 T. The IVIM parameters were obtained from the placenta. The correlation between the f value and postpartum hemorrhage (PPH) and between the f value and transfused units of red blood cells (RBCs) was estimated by linear regression. The correlation between various influencing factors (clinical risk factors, MRI features, and IVIM parameters) and poor outcomes was investigated using univariate and multivariate analyses. RESULT: The interobserver agreement ranged from fair to excellent (k = 0.30-0.88). Multivariate analyses showed that previous cesarean sections, low signal intensity bands on T2WI and the D value were independent risk factors for adverse outcomes. The combination of three risk factors demonstrated the highest AUC of 0.903, with a sensitivity and specificity of 73.10 % and 96.90 %, respectively. Last, f was positively correlated with PPH and units of RBCs transfused. DISCUSSION: Preoperative MRI features and IVIM parameters may be used to predict poor outcomes in patients with invasive placental disorders like PAS.

[Mechanism of Kuntai Capsules in treatment of polycystic ovary syndrome rat models based on AGE-RAGE signal pathway].

This study aims to investigate the impact of Kuntai Capsules(KTC) on polycystic ovarian syndrome(PCOS) rat models and explore the underlying mechanism. Fifty female SD rats were randomly divided into five groups(10 rats in each group), including control group, model group, low-, medium-, and high-dose KTC group. Except for the control group, the other groups were injected with dehydroepiandrosterone(DHEA) combined with a high-fat diet(HFD) to induce the PCOS rat model for 28 days. 0.315, 0.63, and 1.26 g·kg~(-1)·d~(-1) KTC was dissolved in the same amount of normal saline and given to low-, medium-, and high-dose KTC groups by gavage. Both control group and model group were given the same amount of normal saline for 15 days. After administration, fasting blood glucose(FBG) was measured by a glucose meter. Fasting insulin(FINS), luteinizing hormone(LH), testosterone(T), and follicle-stimulating hormone(FSH) were detected by enzyme-linked immunosorbent assay(ELISA), and LH/FSH ratio and insulin resistance index(HOMA-IR) were calculated. The pathological morphology of ovarian tissue was observed by hematoxylin-eosin(HE) staining. The expression levels of collagen α type Ⅲ 1 chain(COL3A1), apoptotic factors Bax, and Bcl-2 were detected using Western blot and immunofluorescence. The mRNA expressions of COL3A1, Bax, and Bcl-2 in ovarian tissue were performed by real-time PCR(RT-PCR). The results show that compared with the control group, the body weight, serum levels of FBG, FINS, LH, T, LH/FSH, and HOMA-IR are higher in model group(P<0.05 or P<0.01), and the level of FSH is lower(P<0.05). In model group, a large number of white blood cells are found in the vaginal exfoliated cells, mainly in the interictal phase. There are more cystic prominences on the surface of the ovary. The thickness of the granular cell layer is reduced, and oocytes are absent. COL3A1 and Bax protein expression levels are increased(P<0.01), while Bcl-2 protein expression levels are decreased(P<0.05) in the ovarian tissue COL3A1 and Bax mRNA expression levels are increased in ovarian tissue(P<0.05). Compared with the model group, the body weight, FBG, FINS, LH, T, LH/FSH, and HOMA-IR in low-, medium-, and high-dose KTC groups are decreased(P<0.05 or P<0.01), while the levels of FSH in medium-, and high-dose KTC groups are increased(P<0.05 or P<0.01). Low-, medium-, and high-dose KTC groups gradually show a stable interictal phase. The surface of the ovary is smooth. Oocytes and mature follicles can be seen in ovarian tissue, and the thickness of the granular cell layer is increased. The expression level of COL3A1 protein decreases in low-and medium-dose KTC groups(P<0.05 or P<0.01), and that of Bax protein decreases in low-dose KTC group(P<0.05 or P<0.01), and the expression level of Bcl-2 protein increases in low-dose KTC group(P<0.01). The expression levels of COL3A1 and Bax mRNA decreased in the low-dose KTC group(P<0.05), while the expression levels of Bcl-2 mRNA increased(P<0.05). In summary, KTC can inhibit ovarian granulosa cell apoptosis and reduce follicular atresia by regulating the AGE-RAGE signaling pathway. It can promote insulin secretion, reduce blood sugar and body weight, restore serum hormone levels, improve symptoms of PCOS, alleviate morphological damage of the ovary, and restore ovarian function, which is of great value in the treatment of PCOS.

A PTER-dependent pathway of taurine metabolism linked to energy balance.

Taurine is a conditionally essential micronutrient and one of the most abundant amino acids in humans1-3. In endogenous taurine metabolism, dedicated enzymes are involved in biosynthesis of taurine from cysteine as well as the downstream derivatization of taurine into secondary taurine metabolites4,5. One such taurine metabolite is N-acetyltaurine6. Levels of N-acetyltaurine are dynamically regulated by diverse physiologic perturbations that alter taurine and/or acetate flux, including endurance exercise7, nutritional taurine supplementation8, and alcohol consumption6,9. While taurine N-acetyltransferase activity has been previously detected in mammalian cells6,7, the molecular identity of this enzyme, and the physiologic relevance of N-acetyltaurine, have remained unknown. Here we show that the orphan body mass index-associated enzyme PTER (phosphotriesterase-related)10 is the principal mammalian taurine N-acetyltransferase/hydrolase. In vitro, recombinant PTER catalyzes bidirectional taurine N-acetylation with free acetate as well as the reverse N-acetyltaurine hydrolysis reaction. Genetic ablation of PTER in mice results in complete loss of tissue taurine N-acetyltransferase/hydrolysis activities and systemic elevation of N-acetyltaurine levels. Upon stimuli that increase taurine levels, PTER-KO mice exhibit lower body weight, reduced adiposity, and improved glucose homeostasis. These phenotypes are recapitulated by administration of N-acetyltaurine to wild-type mice. Lastly, the anorexigenic and anti-obesity effects of N-acetyltaurine require functional GFRAL receptors. Together, these data uncover enzymatic control of a previously enigmatic pathway of secondary taurine metabolism linked to energy balance.

A Multiplex Recombinase-Aided qPCR Assay for Highly Sensitive and Rapid Detection of khe, blaKPC -2, and blaNDM -1 Genes in Klebsiella pneumoniae.

OBJECTIVE: This study aimed to establish a highly sensitive and rapid single-tube, two-stage, multiplex recombinase-aided qPCR (mRAP) assay to specifically detect the khe, blaKPC-2, and blaNDM-1 genes in Klebsiella pneumoniae. METHODS: mRAP was carried out in a qPCR instrument within 1 h. The analytical sensitivities of mRAP for khe, blaKPC-2, and blaNDM-1 genes were tested using recombinant plasmids and dilutions of reference strains. A total of 137 clinical isolates and 86 sputum samples were used to validate the clinical performance of mRAP. RESULTS: mRAP achieved the sensitivities of 10, 8, and 14 copies/reaction for khe, blaKPC-2, and blaNDM-1 genes, respectively, superior to qPCR. The Kappa value of qPCR and mRAP for detecting khe, blaKPC-2, and blaNDM-1 genes was 1, 0.855, and 1, respectively (p < 0.05). CONCLUSION: mRAP is a rapid and highly sensitive assay for potential clinical identification of khe, blaKPC-2, and blaNDM-1 genes in K. pneumoniae.

Biomarker profiling to determine clinical impact of microRNAs in cognitive disorders.

Alzheimer's disease (AD) and post-stroke cognitive impairment (PSCI) are the leading causes of progressive dementia related to neurodegenerative and cerebrovascular injuries in elderly populations. Despite decades of research, patients with these conditions still lack minimally invasive, low-cost, and effective diagnostic and treatment methods. MicroRNAs (miRNAs) play a vital role in AD and PSCI pathology. As they are easily obtained from patients, miRNAs are promising candidates for the diagnosis and treatment of these two disorders. In this study, we performed complete sequencing analysis of miRNAs from 24 participants, split evenly into the PSCI, post-stroke non-cognitive impairment (PSNCI), AD, and normal control (NC) groups. To screen for differentially expressed miRNAs (DE-miRNAs) in patients, we predicted their target genes using bioinformatics analysis. Our analyses identified miRNAs that can distinguish between the investigated disorders; several of them were novel and never previously reported. Their target genes play key roles in multiple signaling pathways that have potential to be modified as a clinical treatment. In conclusion, our study demonstrates the potential of miRNAs and their key target genes in disease management. Further in-depth investigations with larger sample sizes will contribute to the development of precise treatments for AD and PSCI.

Potential of niacin skin flush response in adolescent depression identification and severity assessment: a case-control study.

BACKGROUND: The diagnosis of adolescent Depressive Disorder (DD) lacks specific biomarkers, posing significant challenges. This study investigates the potential of Niacin Skin Flush Response (NSFR) as a biomarker for identifying and assessing the severity of adolescent Depressive Disorder, as well as distinguishing it from Behavioral and Emotional Disorders typically emerging in childhood and adolescence(BED). METHODS: In a case-control study involving 196 adolescents, including 128 Depressive Disorder, 32 Behavioral and Emotional Disorders, and 36 healthy controls (HCs), NSFR was assessed. Depressive symptoms were measured using the Patient Health Questionnaire-9 (PHQ-9) and anxious symptoms with the Generalized Anxiety Disorder 7-item scale (GAD-7). Pearson correlation analysis determined the relationships between NSFR and the severity of depression in DD patients. Receiver Operating Characteristic (ROC) was used to identify DD from BED integrating NSFR data with clinical symptom measures. RESULTS: The adolescent Depressive Disorder group exhibited a higher rate of severe blunted NSFR (21.4%) compared to BED (12.5%) and HC ( 8.3%). Adolescent Depressive Disorder with psychotic symptoms showed a significant increase in blunted NSFR (p = 0.016). NSFR had negative correlations with depressive (r = -0.240, p = 0.006) and anxious (r = -0.2, p = 0.023) symptoms in adolescent Depressive Disorder. Integrating NSFR with three clinical scales improved the differentiation between adolescent Depressive Disorder and BED (AUC increased from 0.694 to 0.712). CONCLUSION: The NSFR demonstrates potential as an objective biomarker for adolescent Depressive Disorder, aiding in screening, assessing severity, and enhancing insights into its pathophysiology and diagnostic precision.

Ts2O Promoted Deoxygenative C-H Dithiocarbonation of Quinoline N-Oxides with Potassium O-Alkyl Xanthates.

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

Improving structural and functional properties of starch-catechin-based green nanofiber mats for active food packaging by electrospinning and crosslinking techniques.

The hydrophilic and low mechanical properties limited the application of starch-based films. In this work, a hydrophobic starch-based nanofiber mat was first successfully prepared from aqueous solution at room temperature by using electrospinning and glutaraldehyde (GTA) vapor phase crosslinking techniques for active packaging applications. Catechin (CAT) was immobilized in the nanofibers by electrospinning, resulting in higher thermal stability (Tdmax = 315.23 °C), antioxidant (DPPH scavenging activity = 94.31 ± 2.70 %) and antimicrobial (inhibition zone diameter = 15.6 ± 0.3 mm) of the fibers, which further demonstrated hydrogen bonding and electrostatic interaction between CAT and fibers. Nanofibers after GTA vapor phase crosslinking exhibited enhanced hydrophobicity (water contact angle: 15.6 ± 1.5° â†’ 93.5 ± 2.3°) and mechanical properties (tensile strength: 1.82 ± 0.06 MPa â†’ 7.64 ± 0.24 MPa, elastic modulus: 19.35 ± 0.63 MPa â†’ 45.34 ± 0.51 MPa). The results demonstrated that preparation of starch-based electrospun nanofiber mats in aqueous system at room temperature overcame the challenges of organic solvent pollution and thermosensitive material encapsulation, while GTA vapor phase crosslinking technique improved the hydrophobicity and mechanical properties of nanofiber mats, which facilitated the application of starch-based materials in the field of packaging.

Network analysis of depression and anxiety symptoms and their associations with life satisfaction among Chinese hypertensive older adults: a cross-sectional study.

Background: Hypertension is one of the most prevalent chronic diseases among the older adult population in China and older adults with hypertension are more susceptible to mental health problems. This study aimed to explore the network structure of depression and anxiety, and their association with life satisfaction (LS) in older adults with hypertension. Methods: A total of 4,993 hypertensive individuals aged 60 and above were selected from the Chinese Longitudinal Healthy Longevity Survey (CLHLS 2017-2018). The design of the CLHLS study was approved by the Campus Institutional Review Board of Duke University (Pro00062871) and the Biomedical Ethics Committee of Peking University (IRB00001052-13,074). The Center for Epidemiologic Studies Depression Scale-10 (CESD-10) and the Generalized Anxiety Disorder Scale-7 (GAD-7) were used to assess depressive and anxiety symptoms. Central and bridge symptoms were identified via "Expected Influence" and "Bridge Expected Influence", respectively. Network stability was assessed using the case-dropping bootstrap technique. Results: Network analysis identified CESD3 (Feeling blue/depressed), GAD4 (Trouble relaxing), and GAD2 (Uncontrollable worry) as the most influential central symptoms in the network of depression and anxiety. Concurrently, GAD1 (Nervousness or anxiety), CESD10 (Sleep disturbances), and CESD1 (Feeling bothered) stand as critical bridge symptoms between depression and anxiety disorders. Moreover, CESD7 (Lack of happiness) exhibited the strongest negative correlation with LS in Chinese hypertensive older adults. Conclusion: This exploratory study represents the first investigation to examine the mutual relationship between depressive and anxiety symptoms among Chinese hypertensive older adults. Interventions addressing targeting bridge symptoms have the potential to alleviate depressive and anxiety symptoms. Furthermore, improving happiness, hope, and sleep quality in this population may mitigate the adverse effects of depression and anxiety on LS.

Comparison of polymerase chain reaction and next-generation sequencing with conventional urine culture for the diagnosis of urinary tract infections: A meta-analysis.

The limitations of conventional urine culture methods can be avoided by using culture-independent approaches like polymerase chain reaction (PCR) and next-generation sequencing (NGS). However, the efficacy of these approaches in this setting is still subject to contention. PRISMA-compliant searches were performed on MEDLINE/PubMed, EMBASE, Web of Sciences, and the Cochrane Database until March 2023. The included articles compared PCR or NGS to conventional urine culture for the detection of urinary tract infections (UTIs). RevMan performed meta-analysis, and the Cochrane Risk of Bias Assessment Tool assessed study quality. A total of 10 selected studies that involved 1,291 individuals were included in this meta-analysis. The study found that PCR has a 99% sensitivity and a 94% specificity for diagnosing UTIs. Furthermore, NGS was shown to have a sensitivity of 90% for identifying UTIs and a specificity of 86%. The odds ratio (OR) for PCR to detect Gram-positive bacteria is 0.50 (95% confidence interval [CI] 0.41-0.61), while the OR for NGS to detect Gram-negative bacteria is 0.23 [95% CI 0.09-0.59]. UTIs are typically caused by Gram-negative bacteria like Escherichia coli and Gram-positive bacteria like Staphylococci and Streptococci. PCR and NGS are reliable, culture-free molecular diagnostic methods that, despite being expensive, are essential for UTI diagnosis and prevention due to their high sensitivity and specificity.

Relationship between fear of falling and quality of life in nursing home residents: The role of activity restriction.

This study investigates the mediating role of activity restriction in the relationship between the fear of falling and health outcomes. This was a cross-sectional study with convenience sampling of 316 nursing home residents. Generalized structural equation modeling was conducted to test the mediating role. The results showed that residents with fear of falling were more likely to restrict their activities and residents who often or always restricted activities reported lower levels of quality of life and higher levels of depression. Severe activity restriction accounted for 75 % of the total effect of fear of falling on quality of life and 69 % of the total effect of fear of falling on depression. Fall prevention efforts should focus on strategies or interventions to reduce residents' excessive fear of falling and promote activity engagement. Physical and social activities will not only prevent future falls but also improve residents' quality of life and mental health.

Numerical Analysis on the Dynamic Response of PVC Foam/Polyurea Composite Sandwich Panels under the Close Air Blast Loading.

This paper explores a novel structure aimed at enhancing its blast resistance performance by adding a layer of polyurea coating to the steel-PVC foam-steel sandwich panel. The response of 13 different arrangements of sandwich panels under explosive loading was studied using numerical simulation. The response process can be divided into three deformation stages: (1) Fluid-structure interaction; (2) Compression of the sandwich panel; (3) Dynamic structural response. The dynamic responses of the various sandwich panels to close-range air blast loading were analyzed based on the deformation characteristics, deflection, effective plastic strain, energy absorption, and pressure of the shock wave. The study draws the following conclusions: Reasonably adding a layer of polyurea to the traditional PVC foam sandwich panel can enhance its resistance to shock wave absorption, with a maximum increase of 29.8%; the optimal arrangement for explosion resistance is steel plate-PVC foam-polyurea-steel plate when the polyurea is coated on the back; and the best quality ratio between polyurea and PVC foam is 1:7 when the polyurea is coated on the front.

Biotransformation of Bioactive Metabolites in Cassiae Semen by Endogenous Enzymes and Probiotics.

The present study evaluated the potential of endogenous enzymes and probiotics in transforming bioactive metabolites to reduce the purgative effect and improve the functional activity of Cassiae Semen and verified and revealed the biotransformation effect of endogenous enzymes. Although probiotics, especially Lactobacillus rhamnosus, exerted the transformation effect, the endogenous enzymes proved to be more effective in transforming the components of Cassiae Semen. After biotransformation by endogenous enzymes for 12 h, the levels of six anthraquinones in Cassiae Semen increased by at least 2.98-fold, and free anthraquinones, total phenolics, and antioxidant activity also showed significant improvement, accompanied by an 82.2% reduction in combined anthraquinones responsible for the purgative effect of Cassiae Semen. Further metabolomic analysis revealed that the biotransformation effect of endogenous enzymes on the bioactive metabolites of Cassiae Semen was complex and diverse, and the biotransformation of quinones and flavonoids was particularly prominent and occurred by three primary mechanisms, hydrolyzation, methylation, and dimerization, might under the action of glycosyl hydrolases, SAM-dependent methyltransferases, and CYP450s. Accordingly, biotransformation by endogenous enzymes emerges as a mild, economical, food safety risk-free, and effective strategy to modify Cassiae Semen into an excellent functional food.

Persulfate-Promoted Carbamoylation/Cyclization of Alkenes: Synthesis of Amide-Containing Quinazolinones.

The incorporation of amide groups into biologically active molecules has been proven to be an efficient strategy for drug design and discovery. In this study, we present a simple and practical method for the synthesis of amide-containing quinazolin-4(3H)-ones under transition-metal-free conditions. This is achieved through a carbamoyl-radical-triggered cascade cyclization of N3-alkenyl-tethered quinazolinones. Notably, the carbamoyl radical is generated in situ from the oxidative decarboxylative process of oxamic acids in the presence of (NH4)2S2O8.

Prevalence of Neutralizing Autoantibodies Against Type I Interferon in a Multicenter Cohort of Severe or Critical COVID-19 Cases in Shanghai.

OBJECTIVE: We sought to explore the prevalence of type I interferon-neutralizing antibodies in a Chinese cohort and its clinical implications during the Omicron variant wave of SARS-CoV-2. METHODS: Type I interferon (IFN) autoantibodies possessing neutralizing capabilities were identified using luciferase assays. The capacity of the autoantibodies for in vitro interference with antiviral activity of IFN was assessed by using a SARS-CoV-2 replicon system. An analysis of the demographic and clinical profiles of patients exhibiting neutralizing antibodies was also conducted. RESULTS: In this cohort, 11.8% of severe/critical cases exhibited the existence of type I IFN-neutralizing antibodies, specifically targeting IFN-α2, IFN-ω, or both, with an elderly male patient tendency. Notably, these antibodies exerted a pronounced inhibitory effect on the antiviral activity of IFN against SARS-CoV-2 under controlled in vitro conditions. Furthermore, a noteworthy correlation was discerned between the presence of these neutralizing antibodies and critical clinical parameters, including C-reactive protein (CRP) levels, D-dimer levels, and lymphocyte counts. CONCLUSION: The presence of type I IFN-neutralizing antibodies is a pervasive risk factor for severe/critical COVID-19 in the Chinese population.

Knowledge, attitudes, and practices towards Kawasaki disease from caregivers of children with Kawasaki disease: a cross-sectional study.

PURPOSE: To examine the knowledge, attitudes, and practices (KAP) of caregivers of children with Kawasaki disease toward Kawasaki disease. METHODS: This cross-sectional study was conducted at four hospitals in China from March 2023 to June 2023. The KAP scores were evaluated using a self-designed questionnaire (Cronbach's α = 0.840; KMO = 0.7381). Correlations between dimension scores were evaluated by Pearson correlation analysis. A structural equation model (SEM) was used to examine the relationships among factors. RESULTS: Of 643 surveyed, 49.50% were male caregivers. The mean knowledge, attitude, and practice scores were 7.12 ± 2.34 (possible range, 0-11), 29.23 ± 5.67 (possible range, 12-60), and 21.57 ± 5.34 (possible range, 6-30). Knowledge correlated with attitude (r = 0.172, P < 0.001) and practice (r = 0.280, P < 0.001). Attitude was significantly related to practice (r = 0.598, P < 0.001). SEM showed knowledge had a positive effect on attitudes (ß = 0.581, P < 0.001) and practices (ß = 0.786, P < 0.001). In addition, attitudes also positively affected practices (ß = 0.554, P < 0.001). Occupation type (ß = 0.598, P = 0.025) and monthly per capita income (ß=-0.750, P = 0.020) had different effects on attitudes, while monthly per capita income also had negative effects on practices (ß=-0.410, P = 0.021). CONCLUSION: Caregivers of children with Kawasaki disease have moderate knowledge and unfavorable attitudes but proactive practices toward this disease. The results could help design an educational intervention to improve KAP, which could translate into better patient management and outcomes. TRIAL REGISTRATION: Not applicable.

A study to untangle the puzzle of urinary incontinence and frailty co-occurrence among older adults: The roles of depression and activity engagement.

AIMS: To explore the co-occurrence of urinary incontinence and frailty by testing the roles of depression and activity engagement guided by the mechanisms of common cause and interaction pathways. DESIGN: A secondary analysis of a 1-year three-wave panel data collected from older nursing home residents in China. METHODS: Changes in depression and activity engagement were regressed on urinary incontinence and frailty incidence underpinned by the common cause mechanism of chronic conditions co-occurrence, and these changes were also taken as mediators linking from frailty to urinary incontinence incidence supported by the interaction pathways' mechanism. RESULTS: A total of 348 older adults were included in this study, and 55.7% were women. The co-occurrence of urinary incontinence and frailty was found in 16.7% of the participants at baseline. Older adults with sole frailty at baseline had almost twice the rate of incident urinary incontinence (32.7%) compared with those without (16.7%) over a 1-year period. The subsample analyses showed that changes in depression and activity engagement failed to significantly predict the incidence of urinary incontinence and frailty. The mediating roles of these changes linking frailty to urinary incontinence incidence were also not statistically significant. CONCLUSION: The co-occurrence of urinary incontinence and frailty is prevalent in older nursing home residents. Older adults with frailty at baseline are more likely to develop urinary incontinence a year later. The common cause and interaction pathways mechanisms for the co-occurrence of urinary incontinence and frailty were not verified with changes in depression and activity engagement. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: The phenomenon of urinary incontinence and frailty co-occurrence should be given extreme emphasis. Although statistically significant findings on the roles of depression and activity engagement were not inferred, this study provides multiple possibilities for future studies to test and depict a clear picture of this co-occurrence. IMPACT: What problem did the study address? This study was designed to test the roles of depression and activity engagement in predicting the incidence of urinary incontinence and frailty, and the mediating roles in linking frailty to urinary incontinence incidence. What were the main findings? Despite the methodological pitfalls in literature have been addressed, neither depression nor activity engagement would significantly predict the incidence of urinary incontinence and frailty in older adults. Their mediating roles in linking frailty to urinary incontinence incidence were also not significant. Where and on whom will the research have an impact? Our findings add important pieces of evidence to promote researchers' understanding and provide an important basis for untangling the puzzle of urinary incontinence and frailty co-occurrence. REPORTING METHOD: The report of this study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement guidelines. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.