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1.
Nucleic Acids Res ; 52(1): 204-222, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37930853

RESUMEN

Aberrant DNA/RNA hybrids (R-loops) formed during transcription and replication disturbances pose threats to genome stability. DHX9 is an RNA helicase involved in R-loop resolution, but how DHX9 is regulated in response to genotoxic stress remains unclear. Here we report that DHX9 is phosphorylated at S321 and S688, with S321 phosphorylation primarily induced by ATR after DNA damage. Phosphorylation of DHX9 at S321 promotes its interaction with γH2AX, BRCA1 and RPA, and is required for its association with R-loops under genotoxic stress. Inhibition of ATR or expression of the non-phosphorylatable DHX9S321A prevents DHX9 from interacting with RPA and R-loops, leading to the accumulation of stress-induced R-loops. Furthermore, depletion of RPA reduces the association between DHX9 and γH2AX, and in vitro binding analysis confirms a direct interaction between DHX9 and RPA. Notably, cells with the non-phosphorylatable DHX9S321A variant exhibit hypersensitivity to genotoxic stress, while those expressing the phosphomimetic DHX9S321D variant prevent R-loop accumulation and display resistance to DNA damage agents. In summary, we uncover a new mechanism by which ATR directly regulates DHX9 through phosphorylation to eliminate stress-induced R-loops.


Asunto(s)
Estructuras R-Loop , Serina , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Daño del ADN , Replicación del ADN , Fosforilación , ARN/metabolismo , Serina/metabolismo , Humanos
2.
Small ; : e2304530, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38415903

RESUMEN

Elevating the working temperature delivers a simple and universal approach to enhance the energy storage performances of supercapacitors owing to the fundamental improvements in ion transportation kinetics. Among all heating methods, introducing green and sustainable photothermal heating on supercapacitors (SCs) is highly desired yet remains an open challenge, especially for developing an efficient and universal photothermal heating strategy that can be generally applied to arbitrary SC devices. Flash-enabled graphene (FG) absorbers are produced through a simple and facile flash reduction process, which can be coated on the surface of any SC devices to lift their working temperature via a photothermal effect, thus, improving their overall performance, including both power and energy densities. With the systematic temperature-dependent investigation and the in-depth numerical simulation of SC performances, an evident enhancement in capacitance up to 65% can be achieved in photothermally enhanced SC coin cell devices with FG photo-absorbers. This simple, practical, and universal enhancement strategy provides a novel insight into boosting SC performances without bringing complexity in electrode fabrication/optimization. Also, it sheds light on the highly efficient utilization of green and renewable photothermal energies for broad application scenarios, especially for energy storage devices.

3.
Small ; : e2402575, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860359

RESUMEN

Effective and rapid heat transfer is critical to improving electronic components' performance and operational stability, particularly for highly integrated and miniaturized devices in complex scenarios. However, current thermal manipulation approaches, including the recent advancement in thermal metamaterials, cannot realize fast and unidirectional heat flow control. In addition, any defects in thermal conductive materials cause a significant decrease in thermal conductivity, severely degrading heat transfer performance. Here, the utilization of silicon-based valley photonic crystals (VPCs) is proposed and numerically demonstrated to facilitate ultrafast, unidirectional heat transfer through thermal radiation on a microscale. Utilizing the infrared wavelength region, the approach achieves a significant thermal rectification effect, ensuring continuous heat flow along designed paths with high transmission efficiency. Remarkably, the process is unaffected by temperature gradients due to the unidirectional property, maintaining transmission directionality. Furthermore, the VPCs' inherent robustness affords defect-immune heat transfer, overcoming the limitations of traditional conduction methods that inevitably cause device heating, performance degradation, and energy waste. The design is fully CMOS compatible, thus will find broad applications, particularly for integrated optoelectronic devices.

4.
Cerebellum ; 23(2): 401-417, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36943575

RESUMEN

Spinocerebellar ataxias (SCAs) are a large and diverse group of autosomal-dominant neurodegenerative diseases. No drugs have been approved for these relentlessly progressive and fatal SCAs. Our previous studies indicate that oxidative stress, neuroinflammation, and neuronal apoptosis are elevated in the SCA17 mice, which are the main therapeutic targets of hyperbaric oxygen treatment (HBOT). HBOT is considered to be an alternative and less invasive therapy for SCAs. In this study, we evaluated the HBOT (2.2 ATA for 14 days) effect and the persistence for the management of SCA17 mice and their wild-type littermates. We found HBOT attenuated the motor coordination and cognitive impairment of SCA17 mice and which persisted for about 1 month after the treatment. The results of several biochemistry and liver/kidney hematoxylin and eosin staining show the HBOT condition has no obvious toxicity in the mice. Immunostaining analyses show that the neuroprotective effect of HBOT could be through the promotion of BDNF production and the amelioration of neuroinflammation. Surprisingly, HBOT executes different effects on the male and female SCA17 mice, including the reduction of neuroinflammation and activation of CaMKII and ERK. This study suggests HBOT is a potential alternative therapeutic treatment for SCA17. Accumulated findings have revealed the similarity in disease pathomechanisms and possible therapeutic strategies in polyQ diseases; therefore, HBOT could be an optional treatment as well as the other polyQ diseases.


Asunto(s)
Disfunción Cognitiva , Oxigenoterapia Hiperbárica , Péptidos , Ataxias Espinocerebelosas , Ratones , Masculino , Femenino , Animales , Oxigenoterapia Hiperbárica/métodos , Enfermedades Neuroinflamatorias , Disfunción Cognitiva/terapia , Ataxias Espinocerebelosas/terapia , Ataxias Espinocerebelosas/tratamiento farmacológico
5.
Chem Rev ; 122(19): 15204-15355, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-35749269

RESUMEN

The outstanding chemical and physical properties of 2D materials, together with their atomically thin nature, make them ideal candidates for metaphotonic device integration and construction, which requires deep subwavelength light-matter interaction to achieve optical functionalities beyond conventional optical phenomena observed in naturally available materials. In addition to their intrinsic properties, the possibility to further manipulate the properties of 2D materials via chemical or physical engineering dramatically enhances their capability, evoking new science on light-matter interaction, leading to leaped performance of existing functional devices and giving birth to new metaphotonic devices that were unattainable previously. Comprehensive understanding of the intrinsic properties of 2D materials, approaches and capabilities for chemical and physical engineering methods, the resulting property modifications and novel functionalities, and applications of metaphotonic devices are provided in this review. Through reviewing the detailed progress in each aspect and the state-of-the-art achievement, insightful analyses of the outstanding challenges and future directions are elucidated in this cross-disciplinary comprehensive review with the aim to provide an overall development picture in the field of 2D material metaphotonics and promote rapid progress in this fast emerging and prosperous field.


Asunto(s)
Óptica y Fotónica , Humanos
6.
Methods ; 214: 28-34, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37116670

RESUMEN

BACKGROUND AND OBJECTIVE: The gold standard for diagnosing epiretinal membranes is to observe the surface of the internal limiting membrane on optical coherence tomography images. The stages of the epiretinal membrane are used to decide the condition of the health of the membrane. The stages are not detected because some of them are similar. To accurately classify the stages, a deep-learning technology can be used to improve the classification accuracy. METHODS: A combinatorial fusion with multiple convolutional neural networks (CNN) algorithms are proposed to enhance the accuracy of a single image classification model. The proposed method was trained using a dataset of 1947 optical coherence tomography images diagnosed with the epiretinal membrane at the Taichung Veterans General Hospital in Taiwan. The images consisted of 4 stages; stages 1, 2, 3, and 4. RESULTS: The overall accuracy of the classification was 84%. The combination of five and six CNN models achieves the highest testing accuracy (85%) among other combinations, respectively. Any combination with a different number of CNN models outperforms any single CNN algorithm working alone. Meanwhile, the accuracy of the proposed method is better than ophthalmologists with years of clinical experience. CONCLUSIONS: We have developed an efficient epiretinal membrane classification method by using combinatorial fusion with CNN models on optical coherence tomography images. The proposed method can be used for screening purposes to facilitate ophthalmologists making the correct diagnoses in general medical practice.


Asunto(s)
Membrana Epirretinal , Humanos , Membrana Epirretinal/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Redes Neurales de la Computación , Algoritmos , Retina
7.
J Formos Med Assoc ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38514373

RESUMEN

BACKGROUND/PURPOSE: We evaluated the utility of combining quantitative pulmonary vasculature measures with clinical factors for predicting pulmonary hemorrhage after computed tomography (CT)-guided lung biopsy. METHODS: Patients who underwent CT-guided lung biopsy were retrospectively included in this study. Clinical and radiographic vasculature variables were evaluated as predictors of pulmonary hemorrhage. The radiographic pulmonary vascular analysis included vessel count, density, diameter, and area, and also blood volume in small vessels with a cross-sectional area ≤5 mm2 (BV5) and total blood vessel volume (TBV) in the lungs. Univariate and multivariate logistic regressions were used to identify the independent risk factors of higher-grade pulmonary hemorrhage and establish the prediction model presented as a nomogram. RESULTS: The study included 126 patients; discovery cohort n = 103, and validation cohort n = 23. All pulmonary hemorrhage, higher-grade (grade ≥2) pulmonary hemorrhage, and hemoptysis occurred in 42.9%, 15.9%, and 3.2% of patients who underwent CT-guided lung biopsies. In the discovery cohort, patients with larger lesion depth (p = 0.013), higher vessel density (p = 0.033), and higher BV5 (p = 0.039) were more likely to experience higher-grade hemorrhage. The nomogram prediction model for higher-grade hemorrhage built by the discovery cohort showed similar performance in the validation cohort. CONCLUSIONS: Higher-grade pulmonary hemorrhage may occur after CT-guided lung biopsy. Lesion depth, vessel density, and BV5 are independent risk factors for higher-grade pulmonary hemorrhage. Nomograms integrating clinical parameters and radiographic pulmonary vasculature measures offer enhanced capability for assessing hemorrhage risk following CT-guided lung biopsy, thereby facilitating improved patient clinical care.

8.
Arch Orthop Trauma Surg ; 144(2): 619-626, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37962635

RESUMEN

PURPOSE: To determine if there is a correlation between lateral tibial slope and long-term clinical results in patients who underwent double-bundle ACL reconstruction. METHODS: We retrospectively reviewed patients that received double-bundle ACL reconstruction at a single institution by a single surgeon from January 2011 to December 2014. All the magnetic resonance imaging were reviewed and lateral tibial slopes (LTS) were recorded by an experienced surgeon and rechecked by the other two authors of this study that specialized in orthopedic knee surgery. The relationship between PROMs measurement and lateral tibial slope were analyzed. The patients were then separated into two groups (LTS > 7.4° and < 7.4°) according to the previous study. RESULTS: A total of 119 patients were enrolled in this study. All enrolled patients were followed for at least 8 years. The PROMS result were negatively correlated with the lateral tibial slope (p values all < 0.001). The patients with high lateral tibial slope had significantly lower PROMS values (Lysholm 94.26 ± 5.61 vs 80.15 ± 8.28, p = 0.013; IKDC 82.99 ± 4.55 vs 70.09 ± 7.15, p = 0.003; Tegner 9.32 ± 0.95 vs 6.85 ± 1.99, p < 0.001). Finally, the LTS cutoff value between patients with "Good" and "Fair" Lysholm score in our study was 7.55 degrees. CONCLUSIONS: Patients with high lateral tibial slope may result in inferior long-term subjective outcomes. The using of double-bundle ACL reconstruction along cannot overcome the negative impact caused by steep lateral tibial slope. A lateral tibial slope of 7.55° may be used as a cut-off for a good clinical outcome. LEVEL OF EVIDENCE: III retrospective comparative prognostic trial.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Humanos , Estudios Retrospectivos , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Articulación de la Rodilla/cirugía , Tibia/cirugía
9.
Surg Endosc ; 37(12): 9173-9182, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37833508

RESUMEN

BACKGROUND: In this retrospective cohort study, we assessed the utility of laparoscopic surgery for diagnostic and therapeutic purposes in patients with anterior abdominal stab wounds (AASWs). We also investigated patient characteristics that might suggest a greater suitability of laparoscopic interventions. METHODS: Over a 25-year span, we analyzed AASW patients who had operations, categorizing them based on the presence of significant intra-abdominal injuries and whether they received laparoscopic surgery or laparotomy. We compared variables such as preoperative conditions, surgical details, and postoperative outcomes. We further evaluated the criteria indicating the necessity of direct laparotomies and traits linked to overlooked injuries in laparoscopic surgeries. RESULTS: Of 142 AASWs surgical patients, laparoscopic surgery was conducted on 89 (62.7%) patients. Only 2 (2.2%) had overlooked injuries after the procedure. Among patients without significant injuries, those receiving laparoscopic surgery had less blood loss than those receiving laparotomy (30.0 vs. 150.0 ml, p = 0.004). Patients who underwent laparoscopic surgery also had shorter hospital stays (significant injuries: 6.0 vs. 11.0 days, p < 0.001; no significant injuries: 5.0 vs. 6.5 days, p = 0.014). Surgical complications and overlooked injury rates were comparable between both surgical methods. Bowel evisceration correlated with higher laparotomy odds (odds ratio = 16.224, p < 0.001), while omental evisceration did not (p = 0.107). CONCLUSIONS: Laparoscopy is a safe and effective method for patients with AASWs, fulfilling both diagnostic and therapeutic needs. For stable AASW patients, laparoscopy could be the preferred method, reducing superfluous nontherapeutic laparotomies.


Asunto(s)
Traumatismos Abdominales , Laparoscopía , Heridas Penetrantes , Heridas Punzantes , Humanos , Estudios Retrospectivos , Heridas Punzantes/cirugía , Heridas Punzantes/diagnóstico , Laparoscopía/métodos , Heridas Penetrantes/cirugía , Abdomen/cirugía , Traumatismos Abdominales/cirugía , Laparotomía/métodos
10.
Sensors (Basel) ; 23(1)2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36617085

RESUMEN

Fused deposition modeling (FDM) is a form of additive manufacturing where three-dimensional (3D) models are created by depositing melted thermoplastic polymer filaments in layers. Although FDM is a mature process, defects can occur during printing. Therefore, an image-based quality inspection method for 3D-printed objects of varying geometries was developed in this study. Transfer learning with pretrained models, which were used as feature extractors, was combined with ensemble learning, and the resulting model combinations were used to inspect the quality of FDM-printed objects. Model combinations with VGG16 and VGG19 had the highest accuracy in most situations. Furthermore, the classification accuracies of these model combinations were not significantly affected by differences in color. In summary, the combination of transfer learning with ensemble learning is an effective method for inspecting the quality of 3D-printed objects. It reduces time and material wastage and improves 3D printing quality.


Asunto(s)
Plásticos , Impresión Tridimensional , Aprendizaje , Aprendizaje Automático
11.
Nano Lett ; 22(14): 6026-6033, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35639615

RESUMEN

Thermochromic materials have been widely applied in energy-efficient buildings, aerospace, textiles, and sensors. Conventional thermochromic materials rely on material phase or structure changes upon thermal stimuli, which only enable a few colors, greatly limiting their applicability. Here, we propose and demonstrate the concept of dynamically tunable thermochromic graphene metamaterials (TGMs), which can achieve continuous color tunability (380-800 nm) with fast (<100 ms) response times. The TGMs are composed of an ultrathin graphene oxide (GO) film on a flexible metal substrate. We demonstrated that external thermal energy can dynamically adjust the water contents in the GO film to manipulate the color of TGMs. An impressive thermochromic sensitivity of 1.11 nm/°C covering a large percentage of the color space has been achieved. Prototype applications for a cup and smartphone have been demonstrated. The reversible TGMs promise great potential for practical applications of temperature sensing in optoelectronic devices, environmental monitoring, and dynamic color modulation.

12.
New Phytol ; 233(2): 766-780, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34625967

RESUMEN

Cytochrome (Cyt) b559 is a key component of the photosystem II complex (PSII) that is essential for its proper functioning and assembly. Site-directed mutants of the model cyanobacterium Synechocystis sp. PCC6803 with mutated heme axial ligands of Cyt b559 have little PSII and are therefore unable to grow photoautotrophically. Here we describe two types of Synechocystis autotrophic transformants that retained the same mutations in Cyt b559 but are able to accumulate PSII and grow photoautotrophically. Whole-genome sequencing revealed that all of these autotrophic transformants carried a variable number of tandem repeats (from 5 to 15) of chromosomal segments containing the psbEFLJ operon. RNA-seq analysis showed greatly increased transcript levels of the psbEFLJ operon in these autotrophic transformants. Multiple copies of the psbEFLJ operon in these transformants were only maintained during autotrophic growth, while its copy numbers gradually decreased under photoheterotrophic conditions. Two-dimensional PAGE analysis of membrane proteins revealed a strong deficiency in PSII complexes in the Cyt b559 mutants that was reversed in the autotrophic transformants. These results illustrate how tandem gene amplification restores PSII accumulation and photoautotrophic growth in Cyt b559 mutants of cyanobacteria, and may serve as an important adaptive mechanism for cyanobacterial survival.


Asunto(s)
Complejo de Proteína del Fotosistema II , Synechocystis , Grupo Citocromo b/genética , Grupo Citocromo b/metabolismo , Citocromos b/genética , Citocromos b/metabolismo , Amplificación de Genes , Complejo de Proteína del Fotosistema II/genética , Complejo de Proteína del Fotosistema II/metabolismo , Synechocystis/metabolismo
13.
Arterioscler Thromb Vasc Biol ; 41(1): e46-e62, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33176446

RESUMEN

OBJECTIVE: Diabetic retinopathy, one of retinal vasculopathy, is characterized by retinal inflammation, vascular leakage, blood-retinal barrier breakdown, and neovascularization. However, the molecular mechanisms that contribute to diabetic retinopathy progression remain unclear. Approach and Results: Tpl2 (tumor progression locus 2) is a protein kinase implicated in inflammation and pathological vascular angiogenesis. Nε-carboxymethyllysine (CML) and inflammatory cytokines levels in human sera and in several diabetic murine models were detected by ELISA, whereas liquid chromatography-tandem mass spectrometry analysis was used for whole eye tissues. The CML and p-Tpl2 expressions on the human retinal pigment epithelium (RPE) cells were determined by immunofluorescence. Intravitreal injection of pharmacological inhibitor or NA (neutralizing antibody) was used in a diabetic rat model. Retinal leukostasis, optical coherence tomography, and H&E staining were used to observe pathological features. Sera of diabetic retinopathy patients had significantly increased CML levels that positively correlated with diabetic retinopathy severity and foveal thickness. CML and p-Tpl2 expressions also significantly increased in the RPE of both T1DM and T2DM diabetes animal models. Mechanistic studies on RPE revealed that CML-induced Tpl2 activation and NADPH oxidase, and inflammasome complex activation were all effectively attenuated by Tpl2 inhibition. Tpl2 inhibition by NA also effectively reduced inflammatory/angiogenic factors, retinal leukostasis in streptozotocin-induced diabetic rats, and RPE secretion of inflammatory cytokines. The attenuated release of angiogenic factors led to inhibited vascular abnormalities in the diabetic animal model. CONCLUSIONS: The inhibition of Tpl2 can block the inflammasome signaling pathway in RPE and has potential clinical and therapeutic implications in diabetes-associated retinal microvascular dysfunction.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Retinopatía Diabética/prevención & control , Inflamasomas/antagonistas & inhibidores , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Neovascularización Retiniana/prevención & control , Epitelio Pigmentado de la Retina/efectos de los fármacos , Anciano , Animales , Células Cultivadas , Estudios Transversales , Bases de Datos Factuales , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/diagnóstico , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/enzimología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/enzimología , Retinopatía Diabética/enzimología , Retinopatía Diabética/etiología , Retinopatía Diabética/patología , Femenino , Humanos , Inflamasomas/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Embarazo , Estudios Prospectivos , Proteínas Proto-Oncogénicas/metabolismo , Neovascularización Retiniana/enzimología , Neovascularización Retiniana/etiología , Neovascularización Retiniana/patología , Epitelio Pigmentado de la Retina/enzimología , Epitelio Pigmentado de la Retina/patología , Transducción de Señal
14.
J Am Chem Soc ; 143(39): 16113-16127, 2021 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-34582167

RESUMEN

Integrating multifunctional nanostructures capable of radiotherapy and photothermal ablation is an emerging alternative in killing cancer cells. In this work, we report a novel plasmonic heterostructure formed by decorating AuPt nanoparticles (NPs) onto the surfaces of CuS nanosheets (AuPt@CuS NSs) as a highly effective nanotheranostic toward dual-modal photoacoustic/computed tomography imaging and enhanced synergistic radiophotothermal therapy. These heterostructures can confer higher photothermal conversion efficiency via the local electromagnetic enhancement as well as a greater radiation dose deposition in the form of glutathione depletion and reactive oxygen species generation. As a result, the depth of tissue penetration is improved, and hypoxia of the tumor microenvironment is alleviated. With synergistic enhancement in the efficacy of photothermal ablation and radiotherapy, the tumor can be eliminated without later recurrence. It is believed that these multifunctional heterostructures will play a vital role in future oncotherapy with the enhanced synergistic effects of radiotherapy and photothermal ablation under the guided imaging of a potential dual-modality system.


Asunto(s)
Cobre/farmacología , Compuestos de Oro/farmacología , Terapia Fototérmica , Compuestos de Platino/farmacología , Radiofármacos/farmacología , Animales , Línea Celular Tumoral , Cobre/química , Femenino , Compuestos de Oro/química , Neoplasias Mamarias Animales , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales , Compuestos de Platino/química , Radiofármacos/química , Distribución Aleatoria
15.
Nat Mater ; 19(1): 94-101, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31659291

RESUMEN

Natural self-assembled three-dimensional photonic crystals such as blue-phase liquid crystals typically assume cubic lattice structures. Nonetheless, blue-phase liquid crystals with distinct crystal symmetries and thus band structures will be advantageous for optical applications. Here we use repetitive electrical pulses to reconfigure blue-phase liquid crystals into stable orthorhombic and tetragonal lattices. This approach, termed repetitively applied field, allows the system to relax between each pulse, gradually transforming the initial cubic lattice into various intermediate metastable states until a stable non-cubic crystal is achieved. We show that this technique is suitable for engineering non-cubic lattices with tailored photonic bandgaps, associated dispersion and band structure across the entire visible spectrum in blue-phase liquid crystals with distinct composition and initial crystal orientation. These field-free blue-phase liquid crystals exhibit large electro-optic responses and can be polymer-stabilized to have a wide operating temperature range and submillisecond response speed, which are promising properties for information display, electro-optics, nonlinear optics, microlasers and biosensing applications.

16.
Int J Mol Sci ; 22(5)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670996

RESUMEN

Human mesenchymal stem cells (hMSCs) possess potential of bone formation and were proposed as ideal material against osteoporosis. Although interrogation of directing effect on lineage specification by physical cues has been proposed, how mechanical stimulation impacts intracellular viscoelasticity during osteogenesis remained enigmatic. Cyto-friendly 3D matrix was prepared with polyacrylamide and conjugated fibronectin. The hMSCs were injected with fluorescent beads and chemically-induced toward osteogenesis. The mechanical properties were assessed using video particle tracking microrheology. Inverted epifluorescence microscope was exploited to capture the Brownian trajectory of hMSCs. Mean square displacement was calculated and transformed into intracellular viscoelasticity. Two different stiffness of microspheres (12 kPa, 1 kPa) were established. A total of 45 cells were assessed. hMSCs possessed equivalent mechanical traits initially in the first week, while cells cultured in rigid matrix displayed significant elevation over elastic (G') and viscous moduli (G") on day 7 (p < 0.01) and 14 (p < 0.01). However, after two weeks, soft niches no longer stiffened hMSCs, whereas the effect by rigid substrates was consistently during the entire differentiation course. Stiffness of matrix impacted the viscoelasticity of hMSCs. Detailed recognition of how microenvironment impacts mechanical properties and differentiation of hMSCs will facilitate the advancement of tissue engineering and regenerative medicine.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Módulo de Elasticidad/fisiología , Matriz Extracelular/fisiología , Células Madre Mesenquimatosas/fisiología , Osteogénesis , Ingeniería de Tejidos , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/citología , Viscosidad
17.
BMC Ophthalmol ; 20(1): 123, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-32228638

RESUMEN

BACKGROUND: Several previous studies reported a greater prevalence of dry eye syndrome (DES) among patients with psychiatric diseases. The aim of this study is to investigate the prevalence and risk factors of DES in patients with psychiatric disorders (PD) using nationwide population-based data in Taiwan. METHODS: This population-based cohort study retrospectively identified patients with PD from 1997 to 2011. Patients with both PD and DES served as the DES cohort, and PD patients without DES comprised the non-DES cohort. PD was defined as a diagnosis of PD (ICD-9-CM 290-319) made by psychiatrists only, with at least three consecutive outpatient visits or at least one inpatient visit. DES was defined as a diagnosis of DES (ICD-9-CM 375.15) and a prescription for an eye lubricant (anatomical therapeutic chemical code, ATC code: S01XA). The main outcome measures were the prevalence of DES in these patients and associated risk factors. RESULTS: A total of 75,650 patients with PD (3665 in the DES cohort and 71,985 in the non-DES cohort) were included in the final analysis. The majority of patients in the DES group were women (72.6%), compared the non-DES group (57.8%). The mean age of patients in the DES cohort was 62.2 ± 14.9, which was significantly older than those in the non-DES group (50.9 ± 17.5). The patients with DES had a significantly greater likelihood of having dementia, bipolar disorder, depression, and neurotic disorders. Conditional regression analyses revealed that patients with dry eye disease were more likely to have schizophrenia (OR = 1.34), bipolar disorder (OR = 1.9), depression (OR = 1.54), and neurotic disorders (OR = 1.62). In addition, patients with DES were more likely to use 1st generation anti-psychotics (OR = 1.28) and had a lower risk of using 2nd generation anti-psychotics (OR = 0.64). CONCLUSION: The study demonstrated that among PD patients, DES is highly prevalence in certain subtypes of PD, such as depression, bipolar disorder, and neurotic disorders, after adjusting for the comorbidities.


Asunto(s)
Síndromes de Ojo Seco/epidemiología , Trastornos Mentales/epidemiología , Anciano , Estudios de Casos y Controles , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud/estadística & datos numéricos , Encuestas Nutricionales/estadística & datos numéricos , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Taiwán/epidemiología
18.
Clin Exp Ophthalmol ; 48(4): 486-499, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31872526

RESUMEN

BACKGROUND: Inherited retinal dystrophy (IRD) is a group of irreversible retinal degenerative disorders with significant genotypic and phenotypic heterogeneity, which cause difficulty in making a precise clinical diagnosis. Furthermore, the mutation spectrum of IRD in Taiwan remains unknown. Therefore, our study focused on investigating the spectrum of mutations among Taiwanese families with IRD using targeted exome sequencing (TES) technology. METHODS: We recruited a total of 60 unrelated Taiwanese families with IRD; most of them were retinitis pigmentosa. We employed TES to investigate 284 candidate genes. Bioinformatics analysis, Sanger sequencing-based co-segregation testing, and computational assessment were performed to validate each mutation and its pathogenicity. The genotype-phenotype correlation was analysed in all patients with mutations defined in the guidelines provided by the American College of Medical Genetics. RESULTS: We successfully identified genetic causes in 32 families (detection rate of 53.3%). Among them, 16 had a sporadic inheritance (16/36, 44.4%); eight had an autosomal recessive inheritance (8/14, 57.1%); four had an autosomal dominant inheritance (4/5, 80%); four had an X-linked inheritance (4/5, 80%). Among 38 pathological mutations in 19 known genes, 20 mutations are reported here for the first time. Novel mutation spectrum and genotype-phenotype correlations were revealed as well. CONCLUSION: Here we achieved a detection rate of 53.3% and elucidated the mutation spectrum in Taiwanese families with IRD for the first time. The results indicated that CYP4V2 and USH2A might be the most common pathogenic genes in IRD patients in Taiwan.


Asunto(s)
Distrofias Retinianas , Análisis Mutacional de ADN , Estudios de Asociación Genética , Humanos , Mutación , Linaje , Fenotipo , Distrofias Retinianas/diagnóstico , Distrofias Retinianas/epidemiología , Distrofias Retinianas/genética , Taiwán/epidemiología
19.
Sensors (Basel) ; 20(20)2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-33066246

RESUMEN

Dental laboratories require manpower resources for manufacturing prostheses and inventory management. In this paper, we developed an automated inventory management system for dental laboratories to improve the production efficiency. A sensing system was developed based on the framework of Internet of things to collect the information of cobalt-chromium disks both in the storage room and manufacturing area, and an expert system was developed to automatically conduct inventory management based on the established rules. The proposed system can reduce the time of recording data and also assist the manager in configuring and managing material orders. The experimental results showed that a large amount of working time is reduced, resulting in the benefits of saving money and improving efficiency in dental manufacturing.


Asunto(s)
Equipo Dental , Eficiencia , Laboratorios Odontológicos/organización & administración , Cromo , Cobalto
20.
J Am Chem Soc ; 141(4): 1725-1734, 2019 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-30604974

RESUMEN

Two-dimensional (2D) nanomaterials are attracting increasing research interest because of their unique properties and promising applications. Here, we report a facile method to manipulate the assembly of nanoparticles (NPs) to fabricate free-standing 2D quasi-nanosheets. The as-generated 2D products are composed of few-layer NPs; that is, their thicknesses are only tens of nanometers but lateral dimensions could be up to several micrometers. Therefore, the novel structure was denoted as 2D "quasi-nanosheets (QNS)". Specifically, several types of building blocks could be assembled into 2D unary, binary, ternary, and even quaternary QNS by a universal procedure. The entire assembly process is carried out in solution and mediated simply by tuning the concentration of ligands surrounding the NPs. In contrast to traditional assembly techniques, even without any substrate or template, these QNS showed exceptionally high stability. They can remain intact for several days without any disassembly regardless of the solvent environment (e.g., water, ethanol, methanol, and hexane). In general, our method has effectively tackled several limitations associated with traditional assembly techniques and allows more freedom in manipulating assembly of NPs, which may hold great potential for future fabrication of 2D devices with rich functionalities.


Asunto(s)
Nanopartículas/química , Nanotecnología , Modelos Moleculares , Conformación Molecular
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