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1.
Small ; 20(6): e2305272, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37702152

RESUMEN

The magnetomechanical actuation of micropillars is developed for the contactless manipulation of miniaturized actuators and microtextured surfaces. Anisotropic geometry of micropillars can significantly enhance the magnetic actuation compared with their isotropic counterparts by directional stress distributions. However, this strategy is not viable for triangular micropillars owing to insufficient anisotropy. In this study, a significant improvement in the magnetic actuation of triangular micropillars using composite magnetic particles is reported. A minute and optimal amount of hard magnetic gamma-ferrite nanorods are hybridized with soft magnetic iron microspheres to generate synergistic effects of magnetic coupling and percolation phenomenon on the magnetic actuation of polymer composites. The addition of 1 wt% face-centered cubic-phased gamma-ferrite nanorods suppresses the magnetic coupling interference of body-centered cubic-phased iron microspheres. Furthermore, the nanorods reduce the percolation threshold by participating in the percolation of the microspheres. A systematic compositional study on the magnetization and magnetorheological properties reveals that the coupling effect dominates the percolation effect at a low magnetic field, whereas the percolation effect governs the magnetic actuation at a high magnetic field. This hybrid approach can help in designing material constituents for effective magnetic actuators and robotic systems that can sensitively respond to an external magnetic field.

2.
Epilepsia ; 65(4): 833-845, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38345387

RESUMEN

The field of epilepsy has undergone substantial advances as we develop novel drugs and devices. Yet considerable challenges remain in developing broadly effective, well-tolerated treatments, but also precision treatments for rare epilepsies and seizure-monitoring devices. We summarize major recent and ongoing innovations in diagnostic and therapeutic products presented at the seventeenth Epilepsy Therapies & Diagnostics Development (ETDD) conference, which occurred May 31 to June 2, 2023, in Aventura, Florida. Therapeutics under development are targeting genetics, ion channels and other neurotransmitters, and many other potentially first-in-class interventions such as stem cells, glycogen metabolism, cholesterol, the gut microbiome, and novel modalities for delivering electrical neuromodulation.


Asunto(s)
Anticonvulsivantes , Epilepsia , Humanos , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Epilepsia/diagnóstico , Convulsiones/tratamiento farmacológico
3.
Epilepsia ; 65(4): 846-860, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135921

RESUMEN

Substantial efforts are underway toward optimizing the diagnosis, monitoring, and treatment of seizures and epilepsy. We describe preclinical programs in place for screening investigational therapeutic candidates in animal models, with particular attention to identifying and eliminating drugs that might paradoxically aggravate seizure burden. After preclinical development, we discuss challenges and solutions in the design and regulatory logistics of clinical trial execution, and efforts to develop disease biomarkers and interventions that may be not only seizure-suppressing, but also disease-modifying. As disease-modifying treatments are designed, there is clear recognition that, although seizures represent one critical therapeutic target, targeting nonseizure outcomes like cognitive development or functional outcomes requires changes to traditional designs. This reflects our increasing understanding that epilepsy is a disease with profound impact on quality of life for the patient and caregivers due to both seizures themselves and other nonseizure factors. This review examines selected key challenges and future directions in epilepsy diagnostics and therapeutics, from drug discovery to translational application.


Asunto(s)
Anticonvulsivantes , Epilepsia , Animales , Humanos , Anticonvulsivantes/uso terapéutico , Calidad de Vida , Epilepsia/diagnóstico , Epilepsia/tratamiento farmacológico , Convulsiones/tratamiento farmacológico , Modelos Animales de Enfermedad
4.
Skeletal Radiol ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249505

RESUMEN

OBJECTIVE: To develop a deep learning algorithm for diagnosing lumbar central canal stenosis (LCCS) using abdominal CT (ACT) and lumbar spine CT (LCT). MATERIALS AND METHODS: This retrospective study involved 109 patients undergoing LCTs and ACTs between January 2014 and July 2021. The dural sac on CT images was manually segmented and classified as normal or stenosed (dural sac cross-sectional area ≥ 100 mm2 or < 100 mm2, respectively). A deep learning model based on U-Net architecture was developed to automatically segment the dural sac and classify the central canal stenosis. The classification performance of the model was compared on a testing set (990 images from 9 patients). The accuracy, sensitivity, and specificity of automatic segmentation were quantitatively evaluated by comparing its Dice similarity coefficient (DSC) and intraclass correlation coefficient (ICC) with those of manual segmentation. RESULTS: In total, 990 CT images from nine patients (mean age ± standard deviation, 77 ± 7 years; six men) were evaluated. The algorithm achieved high segmentation performance with a DSC of 0.85 ± 0.10 and ICC of 0.82 (95% confidence interval [CI]: 0.80,0.85). The ICC between ACTs and LCTs on the deep learning algorithm was 0.89 (95%CI: 0.87,0.91). The accuracy of the algorithm in diagnosing LCCS with dichotomous classification was 84%(95%CI: 0.82,0.86). In dataset analysis, the accuracy of ACTs and LCTs was 85%(95%CI: 0.82,0.88) and 83%(95%CI: 0.79,0.86), respectively. The model showed better accuracy for ACT than LCT. CONCLUSION: The deep learning algorithm automatically diagnosed LCCS on LCTs and ACTs. ACT had a diagnostic performance for LCCS comparable to that of LCT.

5.
J Korean Med Sci ; 39(18): e162, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38742293

RESUMEN

Hereditary hemolytic anemia (HHA) is considered a group of rare hematological diseases in Korea, primarily because of its unique ethnic characteristics and diagnostic challenges. Recently, the prevalence of HHA has increased in Korea, reflecting the increasing number of international marriages and increased awareness of the disease. In particular, the diagnosis of red blood cell (RBC) enzymopathy experienced a resurgence, given the advances in diagnostic techniques. In 2007, the RBC Disorder Working Party of the Korean Society of Hematology developed the Korean Standard Operating Procedure for the Diagnosis of Hereditary Hemolytic Anemia, which has been continuously updated since then. The latest Korean clinical practice guidelines for diagnosing HHA recommends performing next-generation sequencing as a preliminary step before analyzing RBC membrane proteins and enzymes. Recent breakthroughs in molecular genetic testing methods, particularly next-generation sequencing, are proving critical in identifying and providing insight into cases of HHA with previously unknown diagnoses. These innovative molecular genetic testing methods have now become important tools for the management and care planning of patients with HHA. This review aims to provide a comprehensive overview of recent advances in molecular genetic testing for the diagnosis of HHA, with particular emphasis on the Korean context.


Asunto(s)
Anemia Hemolítica Congénita , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , República de Corea , Anemia Hemolítica Congénita/diagnóstico , Anemia Hemolítica Congénita/genética
6.
J Cell Biochem ; 124(10): 1615-1627, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37682868

RESUMEN

The MYCC and MYCN loci are each associated with two upstream open reading frames (uORFs) potentially encoding small proteins (9-21 kDa). We previously demonstrated that uORFs mrtl and MYCHEX1 of MYCC are translated, and their protein products may function to regulate the expression of the "parent" oncogene. We hypothesized that a similar relationship might exist between MYCN and its two uORFs: MYCNOT and MNOP, and investigated the uORF-encoded proteins associated with MYCN to confirm their expression and intracellular location in neuroblastoma and medulloblastoma cells and tissues. MNOP, MYCNOT, mrtl, and MYCHEX1 were readily detected via reverse transcription polymerase chain reaction and Western blot analysis in tumor cell lines. In tumor tissue, MNOP protein expression was confirmed; however, MCYNOT generated from alternative splicing MYCNΔ1b mRNA was not detected. Immunofluorescence staining of MYCNOT displayed multiple bright foci in the nucleus and diffuse staining in the cytoplasm, suggesting that this small protein may function in both the nucleus and cytoplasm. Upon JQ1 treatment, MYCN, MYCNOT, and mrtl decreased substantially or disappeared completely in three different tumor cell lines. Significant levels of apoptosis were observed in each pediatric embryonal tumor cell line but not T47D breast carcinoma cells, suggesting that response to JQ1 transcriptional inhibition is greatest in tumor cells, which depend on MYC to maintain an undifferentiated phenotype. In conclusion, both MYCN uORF-encoded proteins MNOP and MYCNOT, together with the two MYCC uORF-encoded proteins mrtl and MYCHEX1 were detected simultaneously in tumor cell lines and tumor tissues. These four distinct proteins are translated from the "5'-untranslated region" of MYCN or MYCC mRNA and display consistent distribution patterns within the cell. Additional studies to further elucidate the physiological and pathological roles of these uORF-encoded proteins are warranted, as insights gained could inform new strategies for modulating MYC-family oncogenes by targeting their uORFs.

7.
J Pediatr ; 260: 113515, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37244579

RESUMEN

OBJECTIVE: To outline the characteristics of Kikuchi-Fujimoto disease (KFD) in children and analyze factors associated with severe and recurring courses. METHODS: Electronic medical records of children histopathologically diagnosed with KFD at Seoul National University Bundang Hospital from March 2015 to April 2021 were retrospectively reviewed. RESULTS: A total of 114 cases (62 males) were identified. The mean patient age was 12.0 ± 3.5 years. Most patients came to medical attention with cervical lymph node enlargement (97.4%) and fever (85%); 62% had a high-grade fever (≥39°C). Prolonged fever (≥14 days) was seen in 44.3% and was associated with a high-grade fever (P = .004). Splenomegaly, oral ulcer, or rash was present in 10.5%, 9.6%, and 15.8%, respectively. Laboratory findings showed leukopenia, anemia, and thrombocytopenia in 74.1%, 49%, and 24%, respectively. Sixty percent of cases had a self-limited course. Antibiotics were initially prescribed in 20%. A corticosteroid was prescribed in 40% of patients and was associated with oral ulcer (P = .045) and anemia (P = .025). Twelve patients (10.5%) had a recurrence with a median interval of 19 months. No risk factor for recurrence was identified in multivariable analysis. Clinical characteristics of KFD were similar between our current and previous studies. However, antibiotics use decreased (P < .001); nonsteroidal anti-inflammatory drugs use increased (P < .001), and, although statistically not significant, corticosteroid treatment also increased. CONCLUSIONS: Over a span of 18 years, the clinical characteristics of KFD did not change. Patients presenting with high-grade fever, oral ulcer, or anemia may benefit from corticosteroid intervention. All patients should be monitored for recurrence.


Asunto(s)
Linfadenitis Necrotizante Histiocítica , Leucopenia , Úlceras Bucales , Masculino , Humanos , Niño , Adolescente , Linfadenitis Necrotizante Histiocítica/complicaciones , Linfadenitis Necrotizante Histiocítica/diagnóstico , Estudios Retrospectivos , Úlceras Bucales/complicaciones , Úlceras Bucales/tratamiento farmacológico , Corticoesteroides/uso terapéutico , Fiebre/complicaciones , Antibacterianos/uso terapéutico , Leucopenia/tratamiento farmacológico
8.
Pediatr Hematol Oncol ; 39(1): 1-15, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33999757

RESUMEN

OBJECTIVE: This study aimed to pilot PAX ("Play, Act & Interact"), an activity-based emotional support intervention for caregivers of child with cancer, which focuses on addressing their psychological distress and post-traumatic stress symptoms (PTSSs). METHOD: Sixteen mothers whose children were child with cancer participated in this 4-week intervention. Their children (n = 16; 14 males; median age at diagnosis = 10.3 years; the median amount of time from diagnosis = 9 months) were at different treatment stages for a range of different diagnoses. Caregivers completed self-report instruments assessing their psychological distress including PTSSs and family functioning before and after the intervention and a brief open-response exit survey. Paired sample t-tests were computed to compare the pre-and post-intervention scores. RESULTS: The Post-traumatic Stress Disorder Checklist scores significantly decreased from pre- (M = 37.00, SD = 14.75) to post-intervention (M = 32.56, SD = 15.52), t(15) = 4.25, p < .001. There was also a significant difference between pre- (M = 33.5, SD = 3.18) and post-intervention (M = 35.7, SD = 3.14) scores on the Family Adherence subscale of the Family Adaptability and Cohesion Evaluation Scales III, t(15) = -2.58, p = .02. CONCLUSIONS: PAX was a promising intervention for supporting caregivers' PTSSs and family adaptability. Future studies investigating the long-term effects and replicating the current study with more participants and a control group are needed.


Asunto(s)
Cuidadores/psicología , Neoplasias , Apoyo Social , Estrés Psicológico/terapia , Niño , Femenino , Humanos , Masculino , Madres , Neoplasias/terapia , Encuestas y Cuestionarios
9.
Sensors (Basel) ; 22(12)2022 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-35746225

RESUMEN

An uninterruptible power supply (UPS) is a device that can continuously supply power for a certain period when a power outage occurs. UPS devices are used by national institutions, hospitals, and servers, and are located in numerous public places that require continuous power. However, maintaining such devices in good condition requires periodic maintenance at specific time points. Efficient monitoring can currently be achieved using a battery management system (BMS). However, most BMSs are administrator-centered. If the administrator is not careful, it becomes difficult to accurately grasp the data trend of each battery cell, which in turn can lead to a leakage or heat explosion of the cell. In this study, a deep-learning-based intelligent model that can predict battery life, known as the state of health (SoH), is investigated for the efficient operation of a BMS applied to a lithium-based UPS device.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Monitoreo Fisiológico
10.
Nano Lett ; 21(10): 4305-4313, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-33970636

RESUMEN

The family of group IV-VI monochalcogenides has an atomically puckered layered structure, and their atomic bond configuration suggests the possibility for the realization of various polymorphs. Here, we report the synthesis of the first hexagonal polymorph from the family of group IV-VI monochalcogenides, which is conventionally orthorhombic. Recently predicted four-atomic-thick hexagonal GeSe, so-called γ-GeSe, is synthesized and clearly identified by complementary structural characterizations, including elemental analysis, electron diffraction, high-resolution transmission electron microscopy imaging, and polarized Raman spectroscopy. The electrical and optical measurements indicate that synthesized γ-GeSe exhibits high electrical conductivity of 3 × 105 S/m, which is comparable to those of other two-dimensional layered semimetallic crystals. Moreover, γ-GeSe can be directly grown on h-BN substrates, demonstrating a bottom-up approach for constructing vertical van der Waals heterostructures incorporating γ-GeSe. The newly identified crystal symmetry of γ-GeSe warrants further studies on various physical properties of γ-GeSe.

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