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1.
Inorg Chem ; 62(7): 3007-3017, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36753609

RESUMEN

A phosphide nickel(II) phenoxide pincer complex (2) reacts with CO(g) to give a pseudo-tetrahedral nickel(0) monocarbonyl complex (3) possessing a phosphinite moiety. This metal-ligand cooperative (MLC) transformation occurs with a (PPP)Ni scaffold (PPP- = P[2-PiPr2-C6H4]2-), which can accommodate both square planar and tetrahedral geometries. The 2-electron reduction of a nickel(II) species induced by CO coordination involves group transfer to generate a P-O bond. For better mechanistic understanding, a series of nickel(II) phenolate complexes (2a-2e, XC6H4O- (X = OMe, Me, H, and CF3) and pentafluorophenolate) were prepared. Kinetic experimental data reveal that a phenolate species with an electron-withdrawing group reacts faster than those with electron-donating groups. The reaction kinetic experiments were conducted in pseudo-first order conditions at room temperature monitored by UV-vis spectroscopy. A pentafluorophenolate nickel(II) complex (2e) reveals instantaneous reactions even at -40 °C to give a nickel(0) monocarbonyl species (3e) and the reverse reaction is also possible. According to kinetic experiments, the rate determining step (RDS) would be the formation of a 5-coordinate intermediate 4 with a negative entropy value (ΔS‡ < 0), and a positive ρ value based on the Hammett plot indicates that the electron-deficient phenolate leads to a faster CO association. Furthermore, scramble experiments suggest that phenolate de-coordinates from the intermediate 4, which gives a (PPP)Ni-CO species 6. The cationic nickel monocarbonyl intermediate can possess a P--Ni(II), P•-Ni(I), or even a P+-Ni(0) character. Such an inner-sphere electron transfer is suggested when a π-acidic ligand such as CO coordinates to a metal ion. Another possible reaction is homolysis of a Ni-O bond to give P--Ni(I) or P•-Ni(0), when a phenoxyl radical is liberated. Considering the P-O bond formation, closed-shell nucleophilic and open-shell radical pathways are suggested. A phenolate pathway reveals a lower energy state for 2e relative to other complexes (2c and 2d), while its radical pathway undergoes via a higher energy state. Therefore, the formation of a P-O bond may occur with the binding of a closed-shell phenolate to the electron-deficient P center.

2.
Appl Opt ; 58(14): 3676-3684, 2019 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-31158178

RESUMEN

A temporal phase unwrapping method is proposed to generate an unwrapped phase map for a robust three-dimensional (3D) scan. The proposed algorithm seeks to improve the accuracy of the 3D data points obtained through the phase unwrapping process. By applying the k-nearest-neighbor search method, the error bound of the wrapped phase is controlled with improved flexibility. To achieve the desired scanning quality, a series of fringe patterns is generated with multiple phases at three different frequencies. For this method, the pattern is shifted by utilizing a six-step temporal phase unwrapping process. In this unwrapping process, the error bound is controlled by employing the k-nearest-neighbor search method and spatial comparison method to obtain an accurate fringe order. Through our correction method, the wrapped phases can be unwrapped more accurately and thus enhance the robustness of the scanning system compared to previous phase unwrapping methods.

3.
Arch Orthop Trauma Surg ; 138(8): 1165-1172, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29936580

RESUMEN

BACKGROUNDS: Impingement is a risk factor for instability and prosthetic failure following total hip arthroplasty (THA). If the periacetabular osteophytes are not removed at surgery, impingement could occur between the osteophytes and the femoral stem following THA. However, excessive removal of the osteophytes could lead to bleeding from the bone. The aim of our study, therefore, was to locate the site of the impingement and to determine the width of tolerable osteophytes, which does not induce impingement during activities of daily living (ADL), using a three-dimensional simulation. METHODS: On 35 hip models, virtual THA was performed. The acetabular cups were positioned at 45° abduction and 20° anteversion, and the anteversion of femoral stems was 15°. Circular osteophytes with a 30-mm rim were built around the acetabular cup. Fourteen ADL motions were simulated, and the osteophytes were removed until there was no impingement. A clock face was used to map the location and the width of tolerable osteophytes. RESULTS: The impingement mainly occurred in antero-superior and posterior portions around the acetabular cup. Only 4.2-6.2-mm osteophytes were tolerable at the antero-superior portion (12-3 o'clock) and 6.3-7.2-mm osteophytes at the posterior portion (8-10 o'clock) following a total hip arthroplasty. In antero-inferior and postero-superior portions, over-20-mm osteophytes did not induce any impingement. CONCLUSION: Osteophytes in the antero-superior and posterior portion of the acetabulum should be excised during a THA to avoid impingement of the femur-stem construct on the acetabular osteophytes during ADLs.


Asunto(s)
Acetábulo , Artroplastia de Reemplazo de Cadera , Simulación por Computador , Pinzamiento Femoroacetabular , Osteofito , Acetábulo/citología , Acetábulo/patología , Acetábulo/fisiopatología , Acetábulo/cirugía , Pinzamiento Femoroacetabular/patología , Pinzamiento Femoroacetabular/fisiopatología , Pinzamiento Femoroacetabular/prevención & control , Cadera/patología , Cadera/fisiopatología , Cadera/cirugía , Humanos , Modelos Biológicos , Osteofito/patología , Osteofito/fisiopatología
4.
Nat Mater ; 14(7): 701-6, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25915034

RESUMEN

Therapeutics based on transcription factors have the potential to revolutionize medicine but have had limited clinical success as a consequence of delivery problems. The delivery of transcription factors is challenging because it requires the development of a delivery vehicle that can complex transcription factors, target cells and stimulate endosomal disruption, with minimal toxicity. Here, we present a multifunctional oligonucleotide, termed DARTs (DNA assembled recombinant transcription factors), which can deliver transcription factors with high efficiency in vivo. DARTs are composed of an oligonucleotide that contains a transcription-factor-binding sequence and hydrophobic membrane-disruptive chains that are masked by acid-cleavable galactose residues. DARTs have a unique molecular architecture, which allows them to bind transcription factors, trigger endocytosis in hepatocytes, and stimulate endosomal disruption. The DARTs have enhanced uptake in hepatocytes as a result of their galactose residues and can disrupt endosomes efficiently with minimal toxicity, because unmasking of their hydrophobic domains selectively occurs in the acidic environment of the endosome. We show that DARTs can deliver the transcription factor nuclear erythroid 2-related factor 2 (Nrf2) to the liver, catalyse the transcription of Nrf2 downstream genes, and rescue mice from acetaminophen-induced liver injury.


Asunto(s)
ADN/química , Oligonucleótidos/química , Factores de Transcripción/metabolismo , Alanina Transaminasa/metabolismo , Animales , Sistemas de Liberación de Medicamentos , Endosomas/metabolismo , Células Hep G2 , Hepatocitos/citología , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Hígado/metabolismo , Ratones , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Espectrometría de Fluorescencia , Distribución Tisular
5.
Surg Innov ; 21(1): 80-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24145692

RESUMEN

Total knee arthroplasty (TKA) is a surgical method for replacing a degenerated or diseased knee joint that can no longer perform daily functions with an artificial knee implant. In TKA, the artificial knee implant should be inserted such that it aligns well with the mechanical axis of the leg. Thus, precise bone cutting is essential. To improve TKA outcomes, a registration process is performed to locate the predetermined bone cutting area by calculating the position and posture of the femur and tibia. In this article, we propose a patient-specific registration guide that is able to significantly reduce registration time and effort without loss of accuracy. Furthermore, the patient-specific registration guide can be implemented with real-time registration, allowing continuous surgical information to be provided without the insertion of any tracking devices. The precision and accuracy of the proposed registration guide were confirmed through animal tests with a digitizer, stereo camera, and linear motion generator. The error of our registration method, including measurement and guide attachment errors, reached a maximum of 0.321 mm for one pair of cow legs.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Modelos Anatómicos , Cirugía Asistida por Computador/métodos , Animales , Bovinos , Fémur/cirugía , Imagenología Tridimensional , Prótesis de la Rodilla , Imagen por Resonancia Magnética , Ajuste de Prótesis , Reproducibilidad de los Resultados , Tibia/cirugía , Tomografía Computarizada por Rayos X
6.
J Phys Ther Sci ; 26(4): 525-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24764626

RESUMEN

[Purpose] The aim of this study was to present an individualized resistance training method to enable exercise while maintaining an exercise load that is set according to an individual's joint angle-torque using a haptic-based resistance training machine. [Methods] Five participants (machine group) performed individualized shoulder internal and external rotation training with a haptic resistance training machine, while another five participants performed general dumbbell-based shoulder internal and external rotation training for eight weeks. Internal and external rotation powers of subjects were measured using an isokinetic machine before and after training. [Results] The average powers of both shoulder internal and external rotation has been improved after training (25.72%, 13.62%). The improvement in power of external rotation in the machine group was significantly higher than that in the control group. [Conclusion] This study proposes a haptic-based individualized rotator cuff muscle training method. The training protocol maintaining the joint angle-torque profile showed better improvement of shoulder internal/external rotation than dumbbell training.

7.
Nat Commun ; 15(1): 468, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38212312

RESUMEN

Diabetic sensory neuropathy (DSN) is one of the most common complications of type 2 diabetes (T2D), however the molecular mechanistic association between T2D and DSN remains elusive. Here we identify ubiquitin C-terminal hydrolase L1 (UCHL1), a deubiquitinase highly expressed in neurons, as a key molecule underlying T2D and DSN. Genetic ablation of UCHL1 leads to neuronal insulin resistance and T2D-related symptoms in Drosophila. Furthermore, loss of UCHL1 induces DSN-like phenotypes, including numbness to external noxious stimuli and axonal degeneration of sensory neurons in flies' legs. Conversely, UCHL1 overexpression improves DSN-like defects of T2D model flies. UCHL1 governs insulin signaling by deubiquitinating insulin receptor substrate 1 (IRS1) and antagonizes an E3 ligase of IRS1, Cullin 1 (CUL1). Consistent with these results, genetic and pharmacological suppression of CUL1 activity rescues T2D- and DSN-associated phenotypes. Therefore, our findings suggest a complete set of genetic factors explaining T2D and DSN, together with potential remedies for the diseases.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Animales , Resistencia a la Insulina/genética , Ubiquitina Tiolesterasa/genética , Diabetes Mellitus Tipo 2/genética , Drosophila , Neuronas
8.
J Appl Clin Med Phys ; 14(5): 25-42, 2013 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-24036857

RESUMEN

Phase-based respiratory-gated radiotherapy relies on the reproducibility of patient breathing during the treatment. To monitor the positional reproducibility of patient breathing against a 4D CT simulation, we developed a real-time motion verification system (RMVS) using an optical tracking technology. The system in the treatment room was integrated with a real-time position management system. To test the system, an anthropomorphic phantom that was mounted on a motion platform moved on a programmed breathing pattern and then underwent a 4D CT simulation with RPM. The phase-resolved anterior surface lines were extracted from the 4D CT data to constitute 4D reference lines. In the treatment room, three infrared reflective markers were attached on the superior, middle, and inferior parts of the phantom along with the body midline and then RMVS could track those markers using an optical camera system. The real-time phase information extracted from RPM was delivered to RMVS via in-house network software. Thus, the real-time anterior-posterior positions of the markers were simultaneously compared with the 4D reference lines. The technical feasibility of RMVS was evaluated by repeating the above procedure under several scenarios such as ideal case (with identical motion parameters between simulation and treatment), cycle change, baseline shift, displacement change, and breathing type changes (abdominal or chest breathing). The system capability for operating under irregular breathing was also investigated using real patient data. The evaluation results showed that RMVS has a competence to detect phase-matching errors between patient's motion during the treatment and 4D CT simulation. Thus, we concluded that RMVS could be used as an online quality assurance tool for phase-based gating treatments.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador , Técnicas de Imagen Sincronizada Respiratorias , Contencion de la Respiración , Tomografía Computarizada Cuatridimensional , Humanos , Masculino , Movimiento (Física) , Órganos en Riesgo , Fantasmas de Imagen , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología
9.
J Phys Ther Sci ; 25(10): 1299-301, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24259780

RESUMEN

The purpose of this study was to investigate the differences in muscle activation patterns of the biceps brachii (BB) and flexor carpi radialis (FCR) muscles, while measuring the resultant force (RF) at different shoulder flexion angles. [Subjects] Thirteen healthy males (age 24.85±3.4 years, weight; 77.8±7.9 kg; height, 1.7±0.05 m) were enrolled in this study. [Methods] The resultant force was measured by a force transducer . The elbow angle remained constant and the flexion shoulder angle was changed (30°, 45°, 60°, 75° and 90°). [Results] The results of the surface EMG show the largest muscle activities occurred at a shoulder flexion of 75° for BB and 90° for FCR. The largest resultant force was measured at a shoulder flexion angle of 75°. We conclude, that when performing the biceps curl exercise using an arm curl machine, the shoulder should be flexed at 75° to maximize the focus of the exercise for the BB. [Conclusion] These results are useful from the perspective of design as they highlight the differences in the muscle activation of BB and FCR with postural change. Ultimately this knowledge can be used in the design of rehabilitation training for the shoulder as they show that posture can affect muscle activation.

10.
J Control Release ; 354: 188-195, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36596342

RESUMEN

Gene therapy approaches that utilize Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) ribonucleases have tremendous potential to treat human disease. However, CRISPR therapies delivered by integrating viral vectors are limited by potential off-target genome editing caused by constitutive activation of ribonuclease functions. Thus, biomaterial formulations are being used for the delivery of purified CRISPR components to increase the efficiency and safety of genome editing approaches. We previously demonstrated that a novel peptide identified by phage display, TAxI-peptide, mediates delivery of recombinant proteins into neurons. In this report we utilized NeutrAvidin protein to formulate neuron-targeted genome-editing nanoparticles. Cas12a ribonucleases was loaded with biotinylated guide RNA and biotinylated TAxI-peptide onto NeutrAvidin protein to coordinate the formation a targeted ribonuclease protein (RNP) complex. TAxI-RNP complexes are polydisperse with a 14.3 nm radius. The nanoparticles are stable after formulation and show good stability in the presence of normal mouse serum. TAxI-RNP nanoparticles increased neuronal delivery of Cas12a in reporter mice, resulting in induced tdTomato expression after direct injection into the dentate gyrus of the hippocampus. TAxI-RNP nanoparticles also increased genome editing efficacy in hippocampal neurons versus glia. These studies demonstrate the ability to assemble RNP nanoformulations with NeutrAvidin by binding biotinylated peptides and gRNA-loaded Cas12a ribonucleases into protein nanoparticles that target CRISPR delivery to specific cell-types in vivo. The potential to deliver CRISPR nanoparticles to specific cell-types and control off-target delivery to further reduce deleterious genome editing is essential for the creation of viable therapies to treat nervous system disease.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Ratones , Animales , Humanos , Edición Génica/métodos , Ribonucleasas , Péptidos , Neuronas
11.
Adv Drug Deliv Rev ; 200: 115026, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37516409

RESUMEN

The field of gene editing has received much attention in recent years due to its immense therapeutic potential. In particular, gene editing therapeutics, such as the CRISPR-Cas systems, base editors, and other emerging gene editors, offer the opportunity to address previously untreatable disorders. This review aims to summarize the therapeutic applications of gene editing based on mRNA delivery. We introduce gene editing therapeutics using mRNA and focus on engineering and improvement of gene editing technology. We subsequently examine ex vivo and in vivo gene editing techniques and conclude with an exploration of the next generation of CRISPR and base editing systems.


Asunto(s)
Edición Génica , Técnicas de Transferencia de Gen , Humanos , Edición Génica/métodos , ARN Mensajero/genética , Sistemas CRISPR-Cas , Terapia Genética/métodos
12.
Front Mol Biosci ; 10: 1330400, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38234582

RESUMEN

Extracellular vesicles (EVs) are membrane-enclosed particles secreted by a variety of cell types. These vesicles encapsulate a diverse range of molecules, including proteins, nucleic acids, lipids, metabolites, and even organelles derived from their parental cells. While EVs have emerged as crucial mediators of intercellular communication, they also hold immense potential as both biomarkers and therapeutic agents for numerous diseases. A thorough understanding of EV biogenesis is crucial for the development of EV-based diagnostic developments since the composition of EVs can reflect the health and disease status of the donor cell. Moreover, when EVs are taken up by target cells, they can exert profound effects on gene expression, signaling pathways, and cellular behavior, which makes these biomolecules enticing targets for therapeutic interventions. Yet, despite decades of research, the intricate processes underlying EV biogenesis by donor cells and subsequent uptake by recipient cells remain poorly understood. In this review, we aim to summarize current insights and advancements in the biogenesis and uptake mechanisms of EVs. By shedding light on the fundamental mechanisms governing EV biogenesis and delivery, this review underscores the potential of basic mechanistic research to pave the way for developing novel diagnostic strategies and therapeutic applications.

13.
Med Phys ; 38(6): 3006-12, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21815374

RESUMEN

PURPOSE: Optical image-guided systems (e.g., AlignRT, frameless SonArray, ExacTrac) have been used with advantages of avoiding excessive radiation exposure and real-time patient monitoring. Although these systems showed proven accuracy, they need to modify a full facemask for patients with H&N cancer and brain tumor. We developed an optical-based guidance system to manage interfractional and intrafractional setup errors by tracking external markers behind a full facemask. METHODS: Infra-red (IR) reflecting markers were attached on the face of a head phantom and then the phantom was immobilized by a full face thermoplastic mask. A stereo camera system consisting of two CCD cameras was mounted on the inferior wall of treatment room. The stereo camera system was calibrated to reconstruct 3D coordinates of multiple markers with respect to the isocenter using the direct linear transform (DLT) algorithm. The real-time position of the phantom was acquired, through the stereo camera system, by detecting the IR markers behind the full facemask. The detection errors with respect to the reference positions of planning CT images were calculated in six degrees of freedom (6-DOF) by a rigid-body registration technique. RESULTS: The calibration accuracy of the system was in submillimeter (0.33 mm +/- 0.27 mm), which was comparable to others. The mean distance between each of marker positions of optical images and planning CT images was 0.50 mm +/- 0.67 mm. The maximum deviations of 6-DOF registration were less than 1 mm and 1 degrees for the couch translation and rotation, respectively. CONCLUSIONS: The developed system showed the accuracy and consistency comparable to the commercial optical guided systems, while allowing us to simultaneously immobilize patients with a full face thermoplastic mask.


Asunto(s)
Fenómenos Ópticos , Protección Radiológica/instrumentación , Radioterapia Asistida por Computador/instrumentación , Calibración , Marcadores Fiduciales , Humanos , Imagenología Tridimensional , Fantasmas de Imagen , Protección Radiológica/normas , Radioterapia Asistida por Computador/normas , Radioterapia de Intensidad Modulada , Tomografía Computarizada por Rayos X
14.
Med Phys ; 38(6): 3114-24, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21815385

RESUMEN

PURPOSE: To introduce a respiratory motion management technique, so called quasi-breath-hold (QBH) technique and evaluate its feasibility. As a hybrid technique combining free-breathing-based gating (denoted as gating for convenience) and breath-hold (BH), the QBH is designed to overcome typical limitations existing in either one such as phase-shift, residual motion, complexity, and discomfort. METHODS: The QBH is realized using an audio-visual biofeedback system (AVBFS) and a respiratory motion management program (RMMP). The AVBFS, consisting of two infra-red stereo cameras and a head mounted display, monitors respiratory motion and provides dynamic feedback to patients. The RMMP establishes a personalized respiration model based on deep free breathing. The model is further processed to generate a QBH model by inserting a short breath-hold period into the end point of the-end-of-expiration phase. Then the patient is guided to follow the QBH model through the AVBFS. A simulation study with ten volunteers was performed to evaluate the feasibility of the proposed technique. In the simulation, an in-house developed macro program automatically controlled the QBH procedure to virtually deliver an intensity modulated radiation therapy (IMRT) plan. For each volunteer subject, three QBH maneuvers with different breath-hold times of 3, 5, and 7s (denoted as QBH3s, QBH5s, and QBH7s, respectively) and a conventional gating maneuver with 30% duty cycle (for comparison purpose) were applied. External respiration motion signals obtained during the gating window were analyzed to obtain mean absolute error (MAE) between the measured and guiding curve, mean absolute deviation (MAD) of the measured curve, and an inverse uncertainty time histogram (IUTH). RESULTS: Every volunteer successfully performed all of the four maneuvers (1 gating and 3 QBH patterns). The average treatment times were 466.8, 452.3, and 430.8 s for the QBH3s, QBH5s, and QBH7s, respectively, compared to 530.4 s for the gating technique. The mean absolute errors between measured and guiding curve during the gating window were 0.9 +/- 0.7, 0.8 +/- 0.6, 0.7 +/- 0.6, and 0.6 +/- 0.7 mm for the gating, QBH3s, QBH5s, and QBH7s, respectively. The mean absolute deviations of the measured curve during the gating window were 0.7 +/- 0.7, 0.5 +/- 0.5, 0.5 +/- 0.4, and 0.5 +/- 0.6 mm for the gating, QBH3s, QBH5s, and QBH7s, respectively. In the analysis of the IUTH during the gating window, the QBH simulations showed similar (QBH3s) or less (QBH5s and QBH7s) motion uncertainties compared to the gating simulation. CONCLUSIONS: The proposed QBH technique with personalized audio-visual biofeedback was feasible for respiratory motion management. It showed equivalent or less motion uncertainty and shorter treatment time than the conventional free-breathing-based gating technique did. The technique is expected to optimally compromise between patient comfort and treatment efficiency.


Asunto(s)
Retroalimentación Sensorial , Movimiento , Radioterapia/métodos , Respiración , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Incertidumbre , Adulto Joven
15.
Appl Ergon ; 75: 263-271, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30509535

RESUMEN

This study proposes an ingress/egress discomfort prediction algorithm using an in-depth biomechanical method and motion capture database. The ingress/egress motion of the subject was captured using an optical motion capture system and physically adjustable vehicle mock-up. The subjective discomfort evaluation data were also recorded at the same time. The inverse kinematics and inverse dynamics were performed to analyze captured ingress/egress motion. These procedure provide motion and joint torque information on each subject. Based on the analysis results, this study proposes the following novel features: accumulated movement of joint and sum of rectified joint torque. This study conducted a feature selection procedure to identify a relevant feature subset. Recursive feature selection and optimal feature selection methods found the most relevant feature subset with collected subjective responses. Finally, we constructed the prediction model using support vector machine. The prediction model was evaluated through prediction accuracy and statistical analysis. For comparison with the previous study, this study implemented two representative models and compare the result with those of the previous studies using the identical dataset. The effectiveness of proposed algorithm was demonstrated in comparison with previous studies.


Asunto(s)
Algoritmos , Diseño de Equipo/psicología , Ergonomía/métodos , Vehículos a Motor , Adulto , Fenómenos Biomecánicos , Bases de Datos Factuales , Femenino , Humanos , Masculino , Movimiento (Física) , Movimiento , Dispositivos Ópticos , Máquina de Vectores de Soporte , Torque , Adulto Joven
16.
J Biomech ; 84: 27-35, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30558910

RESUMEN

Due to the increased availability of digital human models, the need for knowing human movement is important in product design process. If the human motion is derived rapidly as design parameters change, a developer could determine the optimal parameters. For example, the optimal design of the door panel of an automobile can be obtained for a human operator to conduct the easiest ingress and egress motion. However, acquiring motion data from existing methods provides only unrealistic motion or requires a great amount of time. This not only leads to an increased time consumption for a product development, but also causes inefficiency of the overall design process. To solve such problems, this research proposes an algorithm to rapidly and accurately predict full-body human motion using an artificial neural network (ANN) and a motion database, as the design parameters are varied. To achieve this goal, this study refers to the processes behind human motor learning procedures. According to the previous research, human generate new motion based on past motion experience when they encounter new environments. Based on this principle, we constructed a motion capture database. To construct the database, motion capture experiments were performed in various environments using an optical motion capture system. To generate full-body human motion using this data, a generalized regression neural network (GRNN) was used. The proposed algorithm not only guarantees rapid and accurate results but also overcomes the ambiguity of the human motion objective function, which has been pointed out as a limitation of optimization-based research. Statistical criteria were utilized to confirm the similarity between the generated motion and actual human motion. Our research provides the basis for a rapid motion prediction algorithm that can include a variety of environmental variables. This research contributes to an increase in the usability of digital human models, and it can be applied to various research fields.


Asunto(s)
Movimiento , Redes Neurales de la Computación , Algoritmos , Automóviles , Bases de Datos Factuales , Humanos , Dispositivos Ópticos
17.
Curr Opin Biotechnol ; 52: 25-31, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29486392

RESUMEN

Protein therapeutics based on transcription factors, gene editing enzymes, signaling proteins and protein antigens, have the potential to provide cures for a wide number of untreatable diseases, but cannot be developed into therapeutics due to challenges in delivering them into the cytoplasm. There is therefore great interest in developing strategies that can enable proteins to enter the cytoplasm of cells. In this review article we will discuss recent progress in intracellular protein therapeutics, which are focused on the following four classes of therapeutics, Firstly, vaccine development, secondly, transcription factor therapies, thirdly, gene editing and finally, cancer therapeutics. These exciting new advances raise the prospect of developing cures for several un-treatable diseases.


Asunto(s)
Espacio Intracelular/metabolismo , Proteínas/metabolismo , Genoma , Humanos , Neoplasias/metabolismo , Neoplasias/terapia , Factores de Transcripción/metabolismo , Vacunas/metabolismo
18.
Nat Biomed Eng ; 2(7): 497-507, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30948824

RESUMEN

Technologies that can safely edit genes in the brains of adult animals may revolutionize the treatment of neurological diseases and the understanding of brain function. Here, we demonstrate that intracranial injection of CRISPR-Gold, a nonviral delivery vehicle for the CRISPR-Cas9 ribonucleoprotein, can edit genes in the brains of adult mice in multiple mouse models. CRISPR-Gold can deliver both Cas9 and Cpf1 ribonucleoproteins, and can edit all of the major cell types in the brain, including neurons, astrocytes and microglia, with undetectable levels of toxicity at the doses used. We also show that CRISPR-Gold designed to target the metabotropic glutamate receptor 5 (mGluR5) gene can efficiently reduce local mGluR5 levels in the striatum after an intracranial injection. The effect can also rescue mice from the exaggerated repetitive behaviours caused by fragile X syndrome, a common single-gene form of autism spectrum disorders. CRISPR-Gold may significantly accelerate the development of brain-targeted therapeutics and enable the rapid development of focal brain-knockout animal models.


Asunto(s)
Encéfalo/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Síndrome del Cromosoma X Frágil/patología , Nanopartículas/química , Animales , Conducta Animal , Sistemas CRISPR-Cas/genética , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/metabolismo , Oro/química , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Nanopartículas/toxicidad , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Técnicas de Placa-Clamp , Receptor del Glutamato Metabotropico 5/genética , Receptor del Glutamato Metabotropico 5/metabolismo , Antígenos Thy-1/genética , Antígenos Thy-1/metabolismo
19.
Nat Commun ; 9(1): 3313, 2018 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-30120228

RESUMEN

Engineering of the Cpf1 crRNA has the potential to enhance its gene editing efficiency and non-viral delivery to cells. Here, we demonstrate that extending the length of its crRNA at the 5' end can enhance the gene editing efficiency of Cpf1 both in cells and in vivo. Extending the 5' end of the crRNA enhances the gene editing efficiency of the Cpf1 RNP to induce non-homologous end-joining and homology-directed repair using electroporation in cells. Additionally, chemical modifications on the extended 5' end of the crRNA result in enhanced serum stability. Also, extending the 5' end of the crRNA by 59 nucleotides increases the delivery efficiency of Cpf1 RNP in cells and in vivo cationic delivery vehicles including polymer nanoparticle. Thus, 5' extension and chemical modification of the Cpf1 crRNA is an effective method for enhancing the gene editing efficiency of Cpf1 and its delivery in vivo.


Asunto(s)
Proteínas Bacterianas/metabolismo , Sistemas CRISPR-Cas/genética , Edición Génica , ARN Bacteriano/genética , Animales , Secuencia de Bases , Cationes , Reparación del ADN por Unión de Extremidades/genética , Células HEK293 , Células Hep G2 , Humanos , Lípidos/química , Ratones , Nanopartículas/química , Polímeros/química , Ribonucleoproteínas/metabolismo
20.
Elife ; 62017 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-28462777

RESUMEN

Chemical modification of the gRNA and donor DNA has great potential for improving the gene editing efficiency of Cas9 and Cpf1, but has not been investigated extensively. In this report, we demonstrate that the gRNAs of Cas9 and Cpf1, and donor DNA can be chemically modified at their terminal positions without losing activity. Moreover, we show that 5' fluorescently labeled donor DNA can be used as a marker to enrich HDR edited cells by a factor of two through cell sorting. In addition, we demonstrate that the gRNA and donor DNA can be directly conjugated together into one molecule, and show that this gRNA-donor DNA conjugate is three times better at transfecting cells and inducing HDR, with cationic polymers, than unconjugated gRNA and donor DNA. The tolerance of the gRNA and donor DNA to chemical modifications has the potential to enable new strategies for genome engineering.


Asunto(s)
Sistemas CRISPR-Cas , ADN/química , ADN/genética , Edición Génica/métodos , ARN Guía de Kinetoplastida/química , ARN Guía de Kinetoplastida/genética , Proteínas Bacterianas/metabolismo , Proteína 9 Asociada a CRISPR , Endonucleasas/metabolismo
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