RESUMEN
The paper-folding mechanism has been widely adopted in building of reconfigurable macroscale systems because of its unique capabilities and advantages in programming variable shapes and stiffness into a structure1-5. However, it has barely been exploited in the construction of molecular-level systems owing to the lack of a suitable design principle, even though various dynamic structures based on DNA self-assembly6-9 have been developed10-23. Here we propose a method to harness the paper-folding mechanism to create reconfigurable DNA origami structures. The main idea is to build a reference, planar wireframe structure24 whose edges follow a crease pattern in paper folding so that it can be folded into various target shapes. We realized several paper-like folding and unfolding patterns using DNA strand displacement25 with high yield. Orthogonal folding, repeatable folding and unfolding, folding-based microRNA detection and fluorescence signal control were demonstrated. Stimuli-responsive folding and unfolding triggered by pH or light-source change were also possible. Moreover, by employing hierarchical assembly26 we could expand the design space and complexity of the paper-folding mechanism in a highly programmable manner. Because of its high programmability and scalability, we expect that the proposed paper-folding-based reconfiguration method will advance the development of complex molecular systems.
Asunto(s)
ADN , Conformación de Ácido Nucleico , ADN/química , MicroARNs/análisis , MicroARNs/química , Fluorescencia , Concentración de Iones de HidrógenoRESUMEN
This study aimed to identify the relationship between exercise-induced hypertension and carotid artery intima-media thickness in long-distance runners. Sixty healthy male runners aged 40 to 60 years were assigned to the following three groups based on resting blood pressure and maximal systolic blood pressure during a maximal exercise test: normal blood pressure response, exercise-induced hypertension, and complex hypertension. An exaggerated systolic blood pressure response was defined as a maximal systolic blood pressure+≥+210 mmHg during the maximal exercise test, while carotid intima-media thickness was measured using B-mode ultrasonography. The carotid intima-media thickness mean values were the highest in the complex hypertension group (0.72±0.11 mm), followed by exercise-induced hypertension (0.62±0.12 mm) and normal blood pressure groups (0.55±0.13 mm), with a significant difference between the groups (p+<+0.002). In linear regression analysis, the mean intima-media thickness was independently associated with age (p=0.015) and maximal systolic blood pressure (p=0.046) but not with resting systolic blood pressure. These results suggest that exercise-induced hypertension is associated with carotid intima-media thickness, a surrogate marker of cardiovascular disease, in long-distance runners. Therefore, evaluating the blood pressure response during exercise is important for the early detection of potential cardiovascular disease risks in long-distance runners.
Asunto(s)
Presión Sanguínea , Grosor Intima-Media Carotídeo , Hipertensión , Carrera de Maratón , Humanos , Masculino , Hipertensión/fisiopatología , Hipertensión/etiología , Persona de Mediana Edad , Adulto , Presión Sanguínea/fisiología , Carrera de Maratón/fisiología , Prueba de Esfuerzo , Carrera/fisiologíaRESUMEN
Exercise-induced hypertension (EIH) is thought to be associated with increased cardiovascular (CV) risks. However, no previous studies have investigated the effects of EIH on CV systems in marathon runners without CV risk factors using both 24-hr ambulatory blood pressure (BP) monitoring and exercise stress echocardiography (ESE). This study firstly described differences in CV adaptations according to EIH assessed by both exams. Marathon runners between 35 and 64 years of age without CV risk factors were eligible. All the participants underwent both 24-hr ambulatory BP monitoring and ESE. EIH was defined as a maximal exercise systolic BP≥210 mmHg. The EIH group (n=19) had shorter training history and higher exercise intensity compared to the non-EIH group (n=23). The average systolic BP was higher in the EIH group than in the non-EIH group. Left cardiac chamber size and left ventricular mass (LVM) were also higher in the EIH group compared to the non-EIH group. Maximal BP during ESE was positively correlated with both parameters. Exaggerated BP response during exercise needs to be monitored for pre-emptive measurements before it results in progressive cardiovascular maladaptation.
RESUMEN
A triple-wavelength patterned quantum dot film was fabricated for the light source of digital holography to improve both the axial measurement range and noise reduction. The patterned quantum dot film was fabricated after optimizing the photolithography process condition based on the UV-curable quantum dot solution, which was capable of multiple patterning processes. In addition, an optimized pattern structure was developed by adding TiO2 nanoparticles to both the quantum dot and bank layers to increase the scattering effect for the improved photoluminescence intensity. Finally, the newly developed light source with the balanced spectral distribution was applied to the digital holography, rendering it applicable as an improved light source.
RESUMEN
Mueller matrix spectroscopic ellipsometry (MMSE) is a nondestructive tool for nanostructure analysis, and recently the enhanced computational power, combining neural networks and simulation data, enhance its analysis ability on more complex geometries. This study introduces a deep learning method to realize fast and accurate analysis; predicting nanostructure parameters by pairing Mueller matrices with relatively limited library data and then applying neural network algorithm. Thus, it was realized to predict the width and height of 1D grating structure with an accuracy of MAE below 0.1â nm through the proposed two-step prediction algorithm. Finally, experimental validation on SiO2 grating of 38â nm width and 100â nm height showed a good agreement in the dimensions with reasonable range compared to those measured by scanning electron microscopy.
RESUMEN
Recent advances in DNA nanotechnology led the fabrication and utilization of various DNA assemblies, but the development of a method to control their global shapes and mechanical flexibilities with high efficiency and repeatability is one of the remaining challenges for the realization of the molecular machines with on-demand functionalities. DNA-binding molecules with intercalation and groove binding modes are known to induce the perturbation on the geometrical and mechanical characteristics of DNA at the strand level, which might be effective in structured DNA assemblies as well. Here, we demonstrate that the chemo-mechanical response of DNA strands with binding ligands can change the global shape and stiffness of DNA origami nanostructures, thereby enabling the systematic modulation of them by selecting a proper ligand and its concentration. Multiple DNA-binding drugs and fluorophores were applied to straight and curved DNA origami bundles, which demonstrated a fast, recoverable, and controllable alteration of the bending persistence length and the radius of curvature of DNA nanostructures. This chemo-mechanical modulation of DNA nanostructures would provide a powerful tool for reconfigurable and dynamic actuation of DNA machineries.
Asunto(s)
Benzoxazoles/química , ADN/química , Doxorrubicina/química , Etidio/química , Sustancias Intercalantes/química , Nanoestructuras/química , Compuestos de Quinolinio/química , Benzoxazoles/metabolismo , ADN/genética , ADN/metabolismo , Doxorrubicina/metabolismo , Etidio/metabolismo , Análisis de Elementos Finitos , Sustancias Intercalantes/metabolismo , Ligandos , Microscopía de Fuerza Atómica , Nanotecnología/métodos , Compuestos de Quinolinio/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , EspectrofotometríaRESUMEN
Korean ginseng is a source of functional foods and medicines; however, its productivity is hindered by abiotic stress factors, such as light. This study investigated the impacts of darkness and different light wavelengths on the metabolomics and anti-cancer activity of ginseng extracts. Hydroponically-grown Korean ginseng was shifted to a light-emitting diodes (LEDs) chamber for blue-LED and darkness treatments, while white fluorescent (FL) light treatment was the control. MCF-7 breast cancer and lipopolysaccharide (LPS)-induced BV-2 microglial cells were used to determine chemo-preventive and neuroprotective potential. Overall, 53 significant primary metabolites were detected in the treated samples. The levels of ginsenosides Rb1, Rb2, Rc, Rd, and Re, as well as organic and amino acids, were significantly higher in the dark treatment, followed by blue-LED treatment and the FL control. The dark-treated ginseng extract significantly induced apoptotic signaling in MCF-7 cells and dose-dependently inhibited the NF-κB and MAP kinase pathways in LPS-induced BV-2 cells. Short-term dark treatment increased the content of Rd, Rc, Rb1, Rb2, and Re ginsenosides in ginseng extracts, which promoted apoptosis of MCF-7 cells and inhibition of the MAP kinase pathway in BV-2 microglial cells. These results indicate that the dark treatment might be effective in improving the pharmacological potential of ginseng.
Asunto(s)
Ginsenósidos , Panax , Humanos , Ginsenósidos/uso terapéutico , Extractos Vegetales/química , Panax/química , Células MCF-7 , Oscuridad , Lipopolisacáridos/farmacologíaRESUMEN
Abl family kinases are nonreceptor tyrosine kinases activated by diverse cellular stimuli that regulate cytoskeleton organization, morphogenesis, and adhesion. The catalytic activity of Abl family kinases is tightly regulated in cells by a complex set of intramolecular and intermolecular interactions and post-translational modifications. For example, the platelet-derived growth factor receptor beta (PDGFRß), important for cell proliferation and chemotaxis, is a potent activator of Abl family kinases. However, the molecular mechanism by which PDGFRß engages and activates Abl family kinases is not known. We show here that the Abl2 Src homology 2 domain directly binds to phosphotyrosine Y771 in the PDGFRß cytoplasmic domain. PDGFRß directly phosphorylates multiple novel sites on the N-terminal half of Abl2, including Y116, Y139, and Y161 within the Src homology 3 domain, and Y299, Y303, and Y310 on the kinase domain. Y116, Y161, Y272, and Y310 are all located at or near the Src homology 3/Src homology 2-kinase linker interface, which helps maintain Abl family kinases in an autoinhibited conformation. We also found that PDGFRß-mediated phosphorylation of Abl2 in vitro activates Abl2 kinase activity, but mutation of these four tyrosines (Y116, Y161, Y272, and Y310) to phenylalanine abrogated PDGFRß-mediated activation of Abl2. These findings reveal how PDGFRß engages and phosphorylates Abl2 leading to activation of the kinase, providing a framework to understand how growth factor receptors engage and activate Abl family kinases.
Asunto(s)
Proteínas Tirosina Quinasas/metabolismo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Transducción de Señal , Células 3T3 , Sustitución de Aminoácidos , Animales , Sitios de Unión , Células HEK293 , Humanos , Ratones , Fosforilación , Unión Proteica , Proteínas Tirosina Quinasas/química , Proteínas Tirosina Quinasas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/química , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genéticaRESUMEN
The factor binding inducer of short transcripts-1 (FBI-1) is a POZ-domain Kruppel-like (POK) family of transcription factors and is known as a proto-oncogene or tumor suppressor in various carcinomas. However, the role of FBI-1 on epithelial-to-mesenchymal transition (EMT) and invasiveness in lung cancer remains unknown. Preliminarily, clinical data such as tissue microarray, Kaplan-Meier, and Oncomine were analyzed to confirm the correlation between lung cancer metastasis and FBI-1. To investigate the function of FBI-1 in EMT in lung cancer, EMT was measured in FBI-1-deficient or FBI-1-overexpressing cells. FBI-1 showed decreased expression in tumors metastasized to lymph nodes than in the primary tumor. In addition, it was also associated with improved survival rates of lung cancer patients. FBI-1 knockdown improved E-to-N-cadherin switching, migration, and invasion in A549 cells, similar to the initiation of EMT stimulated by transforming growth factor- ß1 (TGF-ß1). In contrast, overexpression of FBI-1 inhibited the transcription and activation of Smad2, thereby interfering with EMT, despite stimulation by TGF-ß1. These results suggest that FBI-1 plays a negative role in EMT in lung cancer via the TGF-ß1 signaling pathway, implying its use as a new potential therapeutic target and diagnostic indicator for early stage of lung cancer metastasis.
Asunto(s)
Adenocarcinoma del Pulmón , Proteínas de Unión al ADN , Transición Epitelial-Mesenquimal , Neoplasias Pulmonares , Factores de Transcripción , Células A549 , Adenocarcinoma del Pulmón/patología , Línea Celular Tumoral , Movimiento Celular , Proteínas de Unión al ADN/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Invasividad Neoplásica , Transducción de Señal , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Atomic force microscopy (AFM) is one of the most popular imaging and characterizing methods applicable to a wide range of nanoscale material systems. However, high-resolution imaging using AFM generally suffers from a low scanning yield due to its method of raster scanning. Here, a systematic method of data acquisition and preparation combined with a deep-learning-based image super-resolution, enabling rapid AFM characterization with accuracy, is proposed. Its application to measuring the geometrical and mechanical properties of structured DNA assemblies reveals that around a tenfold reduction in AFM imaging time can be achieved without significant loss of accuracy. Through a transfer learning strategy, it can be efficiently customized for a specific target sample on demand.
Asunto(s)
Aprendizaje Profundo , ADN , Microscopía de Fuerza Atómica/métodosRESUMEN
BACKGROUND: Although depression and body weight have been noted as important predictors of cognitive health, it remains unclear how age and sex influence the mechanism by which depressive symptoms and body weight are associated with cognitive functioning. This study examined whether and how the relationships between depressive symptoms and cognitive functioning mediated by body mass index (BMI) differ in terms of age and sex. METHODS: A cross-sectional analysis of a large sample of population-based data (N = 5,619; mean age 70.73 [± 9.07]), derived from the Korean Longitudinal Study of Aging, was conducted with hierarchical mediated-moderation regressions and a PROCESS macro approach in SPSS. Depressive symptoms were measured through the 10-item Center for Epidemiologic Studies Depression (CES-D) scale, and cognitive functioning was assessed with the Korean Mini-Mental State Examination (K-MMSE). RESULTS: The results showed that depressive symptoms were significantly associated with cognitive decline directly and indirectly through reduced BMI. The estimated coefficients indicated that a one standard deviation increase in CES-D scale was associated with about 0.9 decrease in K-MMSE score. However, the indirect relationship between depressive symptoms and cognitive function through BMI emerged only in men or individuals older than 70 years. CONCLUSIONS: The findings suggest that a careful assessment of BMI is warranted for early detection and prevention of cognitive decline related to depressive symptoms, particularly among older men.
Asunto(s)
Cognición , Depresión , Anciano , Índice de Masa Corporal , Estudios Transversales , Depresión/complicaciones , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Pérdida de PesoRESUMEN
Lead (Pb2+) is a developmental neurotoxicant that disrupts the GABA-shift and subsequently causes alterations in the brain's excitation-to-inhibition (E/I) balance. This finding suggests that neurodevelopmental Pb2+ exposures may increase the risk of brain excitability and/or seizure susceptibility. Prior studies have suggested that neurodevelopmental Pb2+ exposures may cause excitotoxicity of cholinergic neurons, but little to no research has further investigated these potential relationships. The present study sought to evaluate the potential for perinatal neurodevelopmental Pb2+ exposures of 150 ppm and 1000 ppm on pilocarpine-induced seizures through the M1 receptor. The study also evaluated the potential for sex- and treatment-dependent differences in brain excitability. The study revealed that Control females have elevated cholinergic brain excitability and decreased GABAergic inhibition in response to pilocarpine-induced seizures. At low Pb2+ exposures, males exhibited more cholinergic brain excitability, whereas at higher Pb2+ exposures, females exhibited more cholinergic brain excitability. Further, taurine was able to provide neuroprotection against pilocarpine-induced seizures in males, whereas females did not reveal such observations. Thus, the present study adds new insights into the potential for cholinergic seizure susceptibility as a function of sex and the dosage ofneurodevelopmental Pb2+ exposure and how taurine may provide selective pharmacodynamics to treat or recover cholinergic system aberrations induced by neurotoxicants.
Asunto(s)
Pilocarpina , Taurina , Colinérgicos/efectos adversos , Femenino , Humanos , Plomo/toxicidad , Masculino , Neurofarmacología , Pilocarpina/toxicidad , Embarazo , Convulsiones/inducido químicamente , Taurina/farmacologíaRESUMEN
Existing inefficient traffic signal plans are causing traffic congestions in many urban areas. In recent years, many deep reinforcement learning (RL) methods have been proposed to control traffic signals in real-time by interacting with the environment. However, most of existing state-of-the-art RL methods use complex state definition and reward functions and/or neglect the real-world constraints such as cyclic phase order and minimum/maximum duration for each traffic phase. These issues make existing methods infeasible to implement for real-world applications. In this paper, we propose an RL-based multi-intersection traffic light control model with a simple yet effective combination of state, reward, and action definitions. The proposed model uses a novel pressure method called Biased Pressure (BP). We use a state-of-the-art advantage actor-critic learning mechanism in our model. Due to the decentralized nature of our state, reward, and action definitions, we achieve a scalable model. The performance of the proposed method is compared with related methods using both synthetic and real-world datasets. Experimental results show that our method outperforms the existing cyclic phase control methods with a significant margin in terms of throughput and average travel time. Moreover, we conduct ablation studies to justify the superiority of the BP method over the existing pressure methods.
Asunto(s)
Aprendizaje , Aprendizaje Automático , RecompensaRESUMEN
Nonintrusive load monitoring (NILM) is a technology that analyzes the load consumption and usage of an appliance from the total load. NILM is becoming increasingly important because residential and commercial power consumption account for about 60% of global energy consumption. Deep neural network-based NILM studies have increased rapidly as hardware computation costs have decreased. A significant amount of labeled data is required to train deep neural networks. However, installing smart meters on each appliance of all households for data collection requires the cost of geometric series. Therefore, it is urgent to detect whether the appliance is used from the total load without installing a separate smart meter. In other words, domain adaptation research, which can interpret the huge complexity of data and generalize information from various environments, has become a major challenge for NILM. In this research, we optimize domain adaptation by employing techniques such as robust knowledge distillation based on teacher-student structure, reduced complexity of feature distribution based on gkMMD, TCN-based feature extraction, and pseudo-labeling-based domain stabilization. In the experiments, we down-sample the UK-DALE and REDD datasets as in the real environment, and then verify the proposed model in various cases and discuss the results.
Asunto(s)
Redes Neurales de la Computación , HumanosRESUMEN
A "person under train" (PUT) incident is a suicidal action involving a person throwing themselves at a moving train. This may cause trauma, including post-traumatic stress disorder (PTSD), to railroad drivers. This study investigated the experiences of railroad drivers of a PUT incident. Data were obtained from two drivers through in-depth interviews and personal narratives regarding their PUT experience and personal lives after the incident. Expressing thoughts through writing was an effective intervention that provided insights into their experience. Thus, an educational program combining mental health management and PTSD treatment is recommended for workers who experience such trauma.
Asunto(s)
Vías Férreas , Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/psicología , Investigación Cualitativa , República de CoreaRESUMEN
Acute myeloid leukaemia (AML) is a blood cancer where undifferentiated myeloid cells are increased in the bone marrow and peripheral blood. As AML is dangerous and shows poor prognosis, many researchers categorised the relevant cytogenetic factors according to risk and prognosis. However, the specific reasons for poor cytogenetic factors remain unknown. We analysed a large data set from AML patients and found that TPD52 expression is elevated in patient groups with poor cytogenetic factors. As the amino acid sequence of TPD52 is evolutionally conserved in vertebrates, zebrafish embryos were used to investigate the function of TPD52. Since myeloid-biased haematopoietic stem cells (HSCs) are relevant to AML, the function of TPD52 in the development of HSCs was investigated. We determined that the zebrafish paralog, tpd52, is important for the maintenance of HSCs through regulation of cell proliferation. As tpd52 is linked to cell proliferation in zebrafish embryos, the proliferation-related gene, CD59, was correlated to TPD52 in every AML cohort with a high correlation coefficient. We suggest that TPD52 can be a novel therapeutic target for AML patients with poor cytogenetic factors. Additionally, more studies between TPD52 and CD59 will further increase the value of TPD52 as a novel target.
Asunto(s)
Proliferación Celular/fisiología , Hematopoyesis/fisiología , Leucemia Mieloide Aguda/metabolismo , Células Mieloides/metabolismo , Proteínas de Neoplasias/metabolismo , Adulto , Animales , Proliferación Celular/genética , Embrión no Mamífero/metabolismo , Femenino , Hematopoyesis/genética , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Pez CebraRESUMEN
A dual-wavelength single light source based on a patterned quantum dot (QD) film was developed with a 405nm LED and bandpass filters to increase color conversion efficiency as well as to decouple the two peaks of dual-wavelength emitted from the QD film. A QD film was patterned laterally with two different sizes of QDs and was combined with bandpass filters to produce a high efficiency and low-speckle dual-wavelength light source. The experimental results showed that the developed dual-wavelength light source can decrease speckle noise to improve the reconstructed image sharpness and the accuracy on height measurement in dual-wavelength digital holography.
RESUMEN
Lithospermum erythrorhizon (L. erythrorhizon), used in traditional medicine, is a potent wound healing, anti-inflammatory and antioxidant plant. However, the effects of L. erythrorhizon on retinal degenerative diseases remain unknown. Here, we explored the protective effects of L. erythrorhizon in in vitro and in vivo retinal degeneration. We found that ethanol extract of L. erythrorhizon (EELE) and the dichloromethane fraction of L. erythrorhizon (MCLE) significantly increased cell viability under glutamate/BSO-induced excitotoxicity/oxidative stress in R28 cells. Treatment with EELE and MCLE reduced the intracellular reactive oxygen species (ROS) and the levels of apoptotic proteins, such as cleaved PARP and cleaved caspase-3. Furthermore, oral administration of EELE and MCLE in an in vivo optic nerve crush mouse model decreased RGC cell death and increased retinal thickness. The major compound between EELE and MCLE was found to be lithospermic acid A (LAA), which has been shown to prevent the elevation of ROS in R28. Therefore, EELE and MCLE have protective effects against the death of retinal cells in vitro and in vivo, and the major compound, LAA, has an antioxidant effect on retinal cells, suggesting that EELE and MCLE could be beneficial agents for retinal degenerative diseases, including glaucoma.
Asunto(s)
Lithospermum/química , Traumatismos del Nervio Óptico/tratamiento farmacológico , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Raíces de Plantas/química , Degeneración Retiniana/tratamiento farmacológico , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Benzofuranos/farmacología , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Depsidos/farmacología , Electroforesis en Gel de Poliacrilamida , Masculino , Ratones , Ratones Endogámicos C57BL , Compresión Nerviosa , Traumatismos del Nervio Óptico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Degeneración Retiniana/metabolismo , Células Ganglionares de la Retina/metabolismo , Tomografía de Coherencia ÓpticaRESUMEN
INTRODUCTION: Reports on patients' satisfaction and preferred characteristics for treatments would be worthwhile when choosing an optimal treatment reflecting patients' perspectives. AIM: To identify the characteristics and treatment patterns of patients with haemophilia A, or their caregivers, in Korea and explore patient preferences and satisfaction with their treatment. METHODS: This cross-sectional, multicentre, observational study was conducted from April 2018 to September 2019 at six nationwide hospitals and three Korea Hemophilia Foundation clinics. Patients aged ≥16 years, or legal caregivers of paediatric patients, who had used factor VIII (FVIII) concentrates for ≥1 month were enrolled. Satisfaction with treatment was measured using the Treatment Satisfaction Questionnaire for Medication (TSQM); preference was evaluated using discrete choice experiment (DCE), with 10 series of two hypothetical treatment options created from D-efficient block design, which varied across five attributes. RESULTS: Overall, 505 patients (mean age 31 years) were enrolled in the study. Patients had received FVIII concentrate for an average of 102.9 months (prophylaxis: 53.5%; on-demand: 22.2%). Mean TSQM scores were 64.6 (effectiveness domain), 97.9 (side effects), 57.1 (convenience) and 66.8 (global satisfaction). The number of vials per injection, and the frequency of drug administration, was significantly associated with treatment satisfaction. According to DCE, simpler treatment options were preferred by patients/caregivers. CONCLUSION: The lowest satisfaction levels were shown in the treatment convenience domain. Patients/parents preferred simpler and easier treatment characteristics. In an attempt to enhance the overall satisfaction of patients and caregivers with treatment, consideration of more convenient characteristics is required in future decisions regarding treatment selection.
Asunto(s)
Hemofilia A , Niño , Estudios Transversales , Hemofilia A/tratamiento farmacológico , Humanos , Recién Nacido , Padres , Prioridad del Paciente , Satisfacción del Paciente , Satisfacción PersonalRESUMEN
DNA nick can be used as a design motif in programming the shape and reconfigurable deformation of synthetic DNA nanostructures, but its mechanical properties have rarely been systematically characterized at the level of base sequences. Here, we investigated sequence-dependent mechanical properties of DNA nicks through molecular dynamics simulation for a comprehensive set of distinct DNA oligomers constructed using all possible base-pair steps with and without a nick. We found that torsional rigidity was reduced by 28-82% at the nick depending on its sequence and location although bending and stretching rigidities remained similar to those of regular base-pair steps. No significant effect of a nick on mechanically coupled deformation such as the twist-stretch coupling was observed. These results suggest that the primary structural role of nick is the relaxation of torsional constraint by backbones known to be responsible for relatively high torsional rigidity of DNA. Moreover, we experimentally demonstrated the usefulness of quantified nick properties in self-assembling DNA nanostructure design by constructing twisted DNA origami structures to show that sequence design of nicks successfully controls the twist angle of structures. Our study illustrates the importance as well as the opportunities of considering sequence-dependent properties in structural DNA nanotechnology.