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Chronic wound management is affected by three primary challenges: bacterial infection, oxidative stress and inflammation, and impaired regenerative capacity. Conventional treatment methods typically fail to deliver optimal outcomes, thus highlighting the urgency to develop innovative materials that can address these issues and improve efficacy. Recent advances in DNA nanotechnology have garnered significant interest, particularly in the field of functional nucleic acid (FNA) nanomaterials, owing to their exceptional biocompatibility, programmability, and therapeutic potential. Among them, FNAs with unique nanostructures have garnered considerable attention. First, they inherit the biological properties of FNAs, including biocompatibility, reactive oxygen species (ROS)-scavenging capabilities, and modulation of cellular functions. Second, based on a precise design, these nanostructures exhibit superior physical properties, stability, and cellular uptake. Third, by leveraging the programmability of DNA strands, FNA nanostructures can be customized to accommodate therapeutic nucleic acids, peptides, and small-molecule drugs, thereby enabling a stable and controlled drug delivery system. These unique characteristics enable the use of FNA nanostructures to effectively address the major challenges in chronic wound management. This review focuses on various FNA nanostructures, including tetrahedral framework nucleic acids (tFNAs), DNA hydrogels, DNA origami, and rolling-circle amplification (RCA) DNA assembly. Additionally, a summary of recent advancements in their design and application for chronic wound management as well as insights for future research in this field are provided.

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In the rapidly evolving field of life sciences and biomedicine, detecting low-abundance biomolecules, and ultraweak biosignals presents significant challenges. This has spurred a rapid development of analytical techniques aiming for increased sensitivity and specificity. These advancements, including signal amplification strategies and the integration of biorecognition events, mark a transformative era in bioanalytical precision and accuracy. A prominent method among these innovations is immuno-rolling circle amplification (immuno-RCA) technology, which effectively combines immunoassays with signal amplification via RCA. This process starts when a targeted biomolecule, such as a protein or cell, binds to an immobilized antibody or probe on a substrate. The introduction of a circular DNA template triggers RCA, leading to exponential amplification and significantly enhanced signal intensity, thus the target molecule is detectable and quantifiable even at the single-molecule level. This review provides an overview of the biosensing strategy and extensive practical applications of immuno-RCA in detecting biomarkers. Furthermore, it scrutinizes the limitations inherent to these sensors and sets forth expectations for their future trajectory. This review serves as a valuable reference for advancing immuno-RCA in various domains, such as diagnostics, biomarker discovery, and molecular imaging.

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Precise identification of small extracellular vesicles (sEVs) is crucial for improving disease diagnosis and treatments, such as bladder cancer. However, accurate isolation and simultaneously quantification of sEVs remain a huge challenge. We have introduced a new technique that combines immobilization with aptamer-assisted dual cycle amplification to isolate and analyze sEVs with high sensitivity. In this method, the CD9 protein antibody is attached to the plate's surface for the initial identification of sEVs, while an aptamer probe is used to detect the exosomal surface protein CD63. We have created an sEVs-surface method that combines target recognition initiated signal recycling and rolling circle amplification (RCA) for signal amplification. This approach allows for the "AND" logic analysis of dual biomarkers, enabling both sEVs quantification and tracing. The proposed approach has a broad detection range and a low limit of detection. Moreover, the established method showed good stability in detecting sEVs with a low coefficient of variation. Our method can effectively isolate certain sEVs and accurately identify them, making it suitable for many uses in biological science, biomedical engineering, and personalized medicine.

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A three-mode biosensor incorporated ratiometric (electrochemical/colorimetric, electrochemical/photothermal) into its design was constructed using DNA-driven magnetic beads (DMBs) as a bridge to detect C. perfringens. It further enhances the accuracy of detection results while maintaining compatibility with applications in multiple scenarios. Briefly, the G-quadruplex was combined with aptamer and immobilized onto magnetic beads through amide-bond, resulting in the integration of DMBs. The DMBs and supernatant were separated by magnetic separation when the target was present. Subsequently, the DMBs were utilized to construct the electrochemical biosensor, whereas the supernatant was used to construct colorimetric and photothermal biosensors. The limits of detection the ratiometric biosensor were ultimately reduced to 0.26 and 0.27 lg CFU g-1, respectively, in comparison to the single three-mode biosensor. Moreover, this biosensor had been applied in real-sample assays successfully. The establishment of this platform provides a new method for detecting pathogens in the fields of food safety and environmental monitoring.

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MicroRNAs (miRNAs) and short RNA fragments (18-25 nt) are crucial biomarkers in biological research and disease diagnostics. However, their accurate and rapid detection remains a challenge, largely due to their low abundance, short length, and sequence similarities. In this study, we report on a highly sensitive, one-step RNA O-circle amplification (ROA) assay for rapid and accurate miRNA detection. The ROA assay commences with the hybridization of a circular probe with the test RNA, followed by a linear rolling circle amplification (RCA) using dUTP. This amplification process is facilitated by U-nick reactions, which lead to an exponential amplification for readout. Under optimized conditions, assays can be completed within an hour, producing an amplification yield up to the microgram level, with a detection limit as low as 0.15 fmol (6 pM). Notably, the ROA assay requires only one step, and the results can be easily read visually, making it user-friendly. This ROA assay has proven effective in detecting various miRNAs and phage ssRNA. Overall, the ROA assay offers a user-friendly, rapid, and accurate solution for miRNA detection. Supplementary Information: The online version contains supplementary material available at 10.1007/s42994-024-00140-0.

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BACKGROUND: Mycotoxins, a class of secondary metabolites produced by molds, are widely distributed in nature and are very common in food contamination. Aflatoxin B1 (AFB1) is a highly stable natural mycotoxin, and many agricultural products are easily contaminated by AFB1, it is important to establish a sensitive and efficient AFB1 detection method for food safety. The fluorescence aptamer sensor has shown satisfactory performance in AFB1 detection, but most of the fluorescence aptasensors are not sensitive enough, so improving the sensitivity of the aptasensor becomes the focus of this work. RESULTS: Herein, an innovative fluorescent aptasensor for AFB1 detection which is based on catalytic hairpin assembly (CHA) and rolling circle amplification (RCA) driven by triple helix molecular switch (THMS) is proposed. A functional single-strand with an AFB1 aptamer, here called an APF, is first designed to lock onto the signal transduction probe (STP), which separates from THMS when target AFB1 is present. Subsequently, STP initiates the RCA reaction along the circular probe, syntheses macro-molecular mass products through repeated triggering sequences, triggers the CHA reaction to produce a large number of H1-H2 structures, which causes FAM to move away from BHQ-1 and recover its fluorescence signal. The fluorescence signal from FAM at 520 nm was collected as the signal output of aptasensor in this work. With high amplification efficiency of RCA and CHA of the fluorescence sensor, resulting in a low LOD value of 2.95 pg mL-1(S/N = 3). SIGNIFICANCE: The successful establishment of the sensor designed in this work shows that the cascade amplification reaction is perfectly applied in the fluorescent aptamer sensor, and the signal amplification through the reaction between DNA strands is a simple and efficient method. In addition, it's also important to remember that the aptasensor can detect other targets only by changing the sequence of the aptamer, without redesigning other DNA sequences in the reaction system.

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Anomalous coronary artery is a rare but potentially life-threatening alteration in the coronary vascular system that is related to an increased risk of myocardial ischemia, ventricular arrhythmias, heart failure, and sudden cardiac death (SCD). Here, we present the case of a young male who presented to the hospital after a witnessed sudden cardiac arrest. Bystander cardiopulmonary resuscitation was started immediately, and normal sinus rhythm was achieved after electrical cardioversion three times. He was admitted to the ICU for further care upon admission. A CT of the chest showed a potential vascular structure in between the aorta and the pulmonary trunk. He underwent cardiac catheterization, which identified minimal coronary artery disease with the anomalous takeoff of the right coronary artery from the left coronary cusp. A cardiac CT scan obtained also showed an anomalous right coronary artery (ARCA) with an inter-arterial course. After explaining available treatment options and obtaining informed consent, a surgical correction by cardiothoracic surgery was performed using the coronary artery bypass graft technique. The patient recovered well after the surgery and was discharged home. After two years of follow-up, he continued to live life normally without any symptoms. Early and accurate diagnosis of an anomalous coronary artery is imperative for timely intervention, as malignant coronary artery diseases can often have a catastrophic presentation with acute coronary syndromes, myocardial infarction, or SCD. We present here a case of successful diagnosis of ARCA and its prompt surgical correction using coronary artery bypass grafting technique in a young adult. Despite the availability of various other treatment options, our case underscores coronary artery bypass grafting as a viable choice for individuals with anomalous coronary arteries, particularly in urgent situations.

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The universal programmed construction of patterned periodic self-assembled nanostructures is a technical challenge in DNA origami nanotechnology but has numerous potential applications in biotechnology and biomedicine. In order to circumvent the dilemma that traditional DNA origami requires a long unusual single-stranded virus DNA as the scaffold and hundreds or even thousands of short strands as staples, we report a method for constructing periodically-self-folded rolling circle amplification products (RPs). The repeating unit is designed to have 3 intra-unit duplexes (inDP1,2,3) and 2 between-unit duplexes (buDP1,2). Based on the complementary pairing of bases, RPs each can self-fold into a periodic grid-patterned ribbon (GR) without the help of any auxiliary oligonucleotide staple. Moreover, by using only an oligonucleotide bridge strand, the GRs are connected together into the larger and denser planar nano-fence-shaped product (FP), which substantially reduces the number of DNA components compared with DNA origami and eliminates the obstacles in the practical application of DNA nanostructures. More interestingly, the FP-based DNA framework can be easily functionalized to offer spatial addressability for the precise positioning of nanoparticles and guest proteins with high spatial resolution, providing a new avenue for the future application of DNA assembled framework nanostructures in biology, material science, nanomedicine and computer science that often requires the ordered organization of functional moieties with nanometer-level and even molecular-level precision.

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The emergence of antibiotic resistance has become a global health crisis, and everyone must arm themselves with wisdom to effectively combat the "silent tsunami" of infections that are no longer treatable with antibiotics. However, the overuse or inappropriate use of unnecessary antibiotics is still routine for administering them due to the unavailability of rapid, precise, and point-of-care assays. Here, a rapid antimicrobial-resistance point-of-care identification device (RAPIDx) is reported for the accurate and simultaneous identification of bacterial species (genotype) and target enzyme activity (phenotype). First, a contamination-free active target enzyme is extracted via the photothermal lysis of preconcentrated bacteria cells on a nanoplasmonic functional layer on-chip. Second, the rapid, precise identification of pathogens is achieved by the photonic rolling circle amplification of DNA on a chip. Third, the simultaneous identification of bacterial species (genotype) and target enzyme activity (phenotype) is demonstrated within a sample-to-answer 45 min operation via the RAPIDx. It is believed that the RAPIDx will be a valuable method for solving the bottleneck of employing on-chip nanotechnology for antibiotic-resistant bioassay and other infectious diseases.

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Climate change and global warming have led to more frequent harmful algal blooms in the last decade. Among these blooms, Heterosigma akashiwo, a golden-brown phytoflagellate, is one of the 40 species with a high potential to form harmful blooms, leading to significant fish mortality. Climate change leads to rising atmospheric and ocean temperatures. These changes, along with altered rainfall patterns and meltwater input, can cause fluctuations in ocean salinity. Elevated atmospheric carbon dioxide (CO2) levels increase water acidity as oceans absorb CO2. This study investigated the effects of temperature, salinity, and CO2 levels on lipid production, hemolytic activity, and toxicity of H. akashiwo using the design of experiment approach, which can be used to investigate the effect of two or more factors on the same response simultaneously in a precise manner with fewer experiments and materials but in a larger region of the factor space. The lipid content was measured using a high-throughput Nile Red method, and the highest level of lipid content was detected at 25°C, a salinity of 30, and a CO2 concentration of 400 ppm. Hemolytic activity was assessed using rabbit blood erythrocytes in a 96-well plate, and the optimal conditions for achieving the highest hemolytic activity were determined at 15°C, a salinity of 10, and a CO2 concentration of 400 ppm. As the chemical structure of the toxin is not known, we used the toxicity against the cell line RTgill-W1 as the cell toxicity proxy. The maximum toxicity was identified at 15°C, a salinity of 10, and a CO2 level of 700 ppm.

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The dual left anterior descending (LAD) artery is a rare anatomic variant of the LAD artery that refers to the duplication of the LAD into a short and long LAD. These two vessels, differentiated based on their lengths, ultimately provide blood supply to the areas normally covered by the LAD. In this case report, we describe an unusual case of a type IV dual LAD system with an additional finding of a separate origin for the short LAD and left circumflex (LCx) artery. These two findings have not been reported together in the literature previously. During diagnostic procedures like coronary angiography or when interpreting cardiac imaging, awareness of these anomalies prevents confusion with pathological conditions such as coronary artery disease or stenosis. Additionally, it is crucial for cardiologists and surgeons to identify these aberrant vessels to avoid any wrongful interventions.

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PURPOSE: The most common anomaly is an anomalous left coronary artery originating from the pulmonary artery. These variants can be different and depend on the location as well as how they present themselves in their anatomical distribution and their symptomatological relationship. For these reasons, this review aims to identify the variants of the coronary artery and how they are associated with different clinical conditions. METHODS: The databases Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS were researched until January 2024. Two authors independently performed the search, study selection, and data extraction. Methodological quality was evaluated using an assurance tool for anatomical studies (AQUA). Pooled prevalence was estimated using a random effects model. RESULTS: A total of 39 studies met the established selection criteria. In this study, 21 articles with a total of 578,868 subjects were included in the meta-analysis. The coronary artery origin variant was 1% (CI = 0.8-1.2%). For this third sample, the funnel plot graph showed an important asymmetry, with a p-value of 0.162, which is directly associated with this asymmetry. CONCLUSIONS: It is recommended that patients whose diagnosis was made incidentally and in the absence of symptoms undergo periodic controls to prevent future complications, including death. Finally, we believe that further studies could improve the anatomical, embryological, and physiological understanding of this variant in the heart.

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Cascaded amplification showed promising potential for detection of trace target miRNAs in molecular diagnosis and prevention of many diseases. In this study, miRNA21 was chosen as the target, and rolling circle amplification (RCA)-based DNA nanoscaffold was integrated with target triggered RNA-cleaving DNAzyme for sensitive detection of miRNA21. That is, the H1 probe was bound with the long-chain product of RCA to self-assemble into DNA nanoscaffold. Target miRNA21 triggered the hybridization chain reaction (HCR) located on the nanoscaffold, and led to rapid proximity of DNAzyme fragments modified at both ends of the H2 probe, which realized the cyclic cleavage of self-quenching substrate probe efficiently, and the fluorescence signal was restored. The results demonstrated that the proposed assay was sensitive, 0.76 pM of miRNA21 can be detected. The proposed assay was specific; only one-base mismatched miRNA21 can be effectively recognized, other nucleic acid sequence and the serum matrix did not cause any interference. The proposed assay was accurate; recoveries from 82.1 to 115.0% can be obtained in the spiked fetal bovine serum (FBS). The flexible and programmable characteristics of DNA nanoscaffold and DNAzyme provide a confident and robust strategy for more sensitive nucleic acid detection, and can be developed to be a universal sensing platform for detecting other miRNAs just needing modification on the corresponding sequence of H1 probe in HCR.

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In this study, we investigated the effectiveness of regional citrate anticoagulation continuous renal replacement therapy (RCA-CRRT) in reducing blood calcium levels in three patients with hypercalcemia crisis caused by different etiologies. The sodium citrate chelation of calcium ions was utilized as an anticoagulant for treating severely affected patients. By adjusting the citrate anticoagulant dose and monitoring treatment indicators, RCA-CRRT parameters were actively modified to alleviate the hypercalcemia crisis and provide time for surgery or specialized treatment. Two patients experienced rapid and effective reductions in blood calcium levels, allowing for further treatment, while the third patient exhibited a repeated increase in blood calcium, which eventually decreased after parathyroid adenoma resection, leading to clinical discharge. Our findings suggest that RCA-CRRT can help alleviate hypercalcemia crisis, stabilize the patient's internal environment, and provide valuable time for clinical treatment in cases of various medical conditions causing abnormal blood calcium elevations.

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Here, a separation-free and label-free portable aptasensor is developed for rapid and sensitive analysis of tumor-derived exosomes (TEXs). It integrated a parallel rolling circle amplification (RCA) reaction, selective binding of metal ions or small molecules to nucleic acid-specific conformations, and a low-cost, highly sensitive handheld fluorometer. Lung cancer, for example, is targeted with two typical biomarkers (mucin 1 and programmed cell death ligand 1 (PD-L1)) on its exosomes. The affinity of aptamers to the targets modulated the amount of RCA products (T-Hg2+-T and cytosine (C)-rich single-stranded DNA), which in turn affected the fluorescence intensity of quantum dots (QDs) and methylene blue (MB). The results revealed that the limit of detection (LOD) of the handheld fluorometer for cell-derived exosomes can be as low as 30 particles mL-1. Moreover, its specificity, sensitivity, and area under the curve (AUC) are 93% (14/15), 92% (23/25), and 0.956, as determined by the analysis of 40 clinical samples. Retesting 16 of these samples with the handheld fluorometer yielded strong concordance between the fluorometer results and those acquired from clinical computed tomography (CT) and pathology.

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The isolated origin of the left coronary artery (LCA) ostium at the level of the sinotubular junction (STJ) has been described previously. Congenital absence of the left circumflex (LCx) coronary artery has also been documented with superdominant right coronary arterial circulation, either in the presence or absence of coronary artery obstruction. Earlier literature has linked the association of an absent LCx coronary artery with a superdominant right coronary artery (SRCA) but not with a hypoplastic LCx coronary artery (HLCx). The present case report details the case of a 37-year-old thin, athletic male with the risk factors of diabetes and hypertension who was admitted to the emergency unit of our hospital for losing consciousness while bicycling in the street. The current report establishes a combined association of LCA anomaly origin at STJ level along with HLCx and SRCA condition with the burden of mild to moderate coronary artery disease involving proximal left anterior descending artery, LCx, and mid right coronary artery in the literature for the first time. Further, the case report advocated that the presented case carries the risk of malignancy. Hence, with the advancement of modern imaging technologies, computed tomography angiography should be the first choice of imaging modality rather than coronary angiography to prevent fatal outcomes. Interventional cardiologists, cardiothoracic surgeons, and radiologists should have properly defined knowledge of coronary artery anatomy and associated pathology, as it is important for coronary cannulation or any coronary interventions.

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Drought is one of the natural stresses that greatly impact plants. Castor bean (Ricinus communis L.) is an oil crop with high economic value. Drought is one of the factors limiting castor bean growth. The drought resistance mechanisms of castor bean have become a research focus. In this study, we used castor germinating embryos as experimental materials, and screened genes related to drought resistance through physiological measurements, proteomics and metabolomics joint analysis; castor drought-related genes were subjected to transient silencing expression analysis in castor leaves to validate their drought-resistant functions, and heterologous overexpression and backward complementary expression in Arabidopsis thaliana, and analysed the mechanism of the genes' response to the participation of Arabidopsis thaliana in drought-resistance.Three drought tolerance-related genes, RcECP 63, RcDDX 31 and RcA/HD1, were obtained by screening and analysis, and transient silencing of expression in castor leaves further verified that these three genes corresponded to drought stress, and heterologous overexpression and back-complementary expression of the three genes in Arabidopsis thaliana revealed that the function of these three genes in drought stress response.In this study, three drought tolerance related genes, RcECP 63, RcDDX 31 and RcA/HD1, were screened and analysed for gene function, which were found to be responsive to drought stress and to function in drought stress, laying the foundation for the study of drought tolerance mechanism in castor bean.

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Tracking trace protein analytes in precision diagnostics is an ongoing challenge. Here, we developed an ultrasensitive detection method for the detection of SARS-CoV-2 nucleocapsid (N) protein by combining enzyme-linked immunosorbent assay (ELISA) with the clustered regularly interspaced short palindromic repeat/CRISPR-associated protein (CRISPR/Cas) system. First, the SARS-CoV-2 N protein bound by the capture antibody adsorbed on the well plate was sequentially coupled with the primary antibody, biotinylated secondary antibody, and streptavidin (SA), followed by biotin primer binding to SA. Subsequently, rolling circle amplification was initiated to generate ssDNA strands, which were targeted by CRISPR/Cas12a to cleave the FAM-ssDNA-BHQ1 probe in trans to generate fluorescence signals. We observed a linear relationship between fluorescence intensity and the logarithm of N protein concentration ranging from 3 fg/mL to 3 × 107 fg/mL. The limit of detection (LOD) was 1 fg/mL, with approximately nine molecules in 1 µL of the sample. This detection sensitivity was 4 orders magnitude higher than that of commercially available ELISA kits (LOD: 5.7 × 104 fg/mL). This method was highly specific and sensitive and could accurately detect SARS-CoV-2 pseudovirus and clinical samples, providing a new approach for ultrasensitive immunoassay of protein biomarkers.

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Metacestodiasis is an infectious disease caused by the larval stage of cestode parasites. This disease poses a serious health hazard to wildlife, livestock, and humans, and it incurs substantial economic losses by impacting the safety of the livestock industry, the quality of meat production, and public health security. Unfortunately, there is currently no available molecular diagnostic method capable of distinguishing cysticercus- and Echinococcus-derived microRNAs (miRNAs) from other helminthes and hosts in the plasma of metacestode-infected animals. This study aims to develop a specific, sensitive, and cost-efficient molecular diagnostic method for cysticercosis and echinococcosis, particularly for early detection. The study developed a rolling circular amplification (RCA)-assisted CRISPR/Cas9 detection method based on parasite-derived miRNA let-7-5p. Using a series of dilutions of the let-7 standard, the limit of detection (LOD) of the qPCR, RCA, and RCA-assisted CRISPR/Cas9 methods was compared. The specificity of qPCR and CRISPR/Cas9 was evaluated using four artificially synthesized let-7 standards from different species. A total of 151 plasma samples were used to evaluate the diagnostic performance. Additionally, the study also assessed the correlation between plasma levels of let-7-5p, the number of Taenia pisiformis cysticerci, and the weight of Echinococcus multilocularis cysts. The results demonstrated that the RCA-assisted CRISPR/Cas9 assay could significantly distinguish let-7 from cestodes and other species, achieving a LOD of 10 aM; the diagnostic sensitivity and specificity for rabbit cysticercosis and mouse E. multilocularis were 100% and 97.67%, and 100% and 100%, respectively. Notably, let-7-5p gradually increased in the plasma of T. pisiformis-infected rabbits from 15 days post infection (dpi), peaked at 60 dpi, and persisted until 120 dpi. In E. multilocularis-infected mice, let-7-5p gradually increased from 15 dpi and persisted until 90 dpi. Furthermore, the expression of let-7-5p positively correlated with the number of cysticerci and cyst weight. These results indicated that the let-7-5p-based RCA-assisted CRISPR/Cas9 assay is a sensitive and specific detection method that can be used as a universal diagnostic method for metacestodiasis, particularly for early diagnosis (15 dpi).

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An anomalous right coronary artery (RCA) takeoff, a rare congenital condition often characterized by an interarterial RCA course between the pulmonary artery and the ascending aorta, can lead to symptoms of angina pectoris (chest pain) or even sudden cardiac death (SCD) due to compression of the RCA, although most patients remain asymptomatic. In this case report, we highlight the utility of computed tomography angiography (CTA)-derived fractional flow reserve (FFR), a minimally invasive technique used to assess the hemodynamic significance of coronary lesions, in the risk stratification and surgical decision-making process for a 46-year-old female patient presenting with exertional dyspnea and an anomalous RCA takeoff with an interarterial course. The information obtained from this imaging modality was instrumental in determining that surgical repair did not need to be performed urgently and could be scheduled as an elective case in the future.