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1.
Nucleic Acids Res ; 50(1): 306-321, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-34904669

RESUMEN

Poly(A)-binding protein (PABP) is a translation initiation factor that interacts with the poly(A) tail of mRNAs. PABP bound to poly(A) stimulates translation by interacting with the eukaryotic initiation factor 4G (eIF4G), which brings the 3' end of an mRNA close to its 5' m7G cap structure through consecutive interactions of the 3'-poly(A)-PABP-eIF4G-eIF4E-5' m7G cap. PABP is a highly abundant translation factor present in considerably larger quantities than mRNA and eIF4G in cells. However, it has not been elucidated how eIF4G, present in limited cellular concentrations, is not sequestered by mRNA-free PABP, present at high cellular concentrations, but associates with PABP complexed with the poly(A) tail of an mRNA. Here, we report that RNA-free PABPs dimerize with a head-to-head type configuration of PABP, which interferes in the interaction between PABP and eIF4G. We identified the domains of PABP responsible for PABP-PABP interaction. Poly(A) RNA was shown to convert the PABP-PABP complex into a poly(A)-PABP complex, with a head-to-tail-type configuration of PABP that facilitates the interaction between PABP and eIF4G. Lastly, we showed that the transition from the PABP dimer to the poly(A)-PABP complex is necessary for the translational activation function.


Asunto(s)
Proteínas de Unión a Poli(A)/química , Línea Celular Tumoral , Factor 4G Eucariótico de Iniciación/metabolismo , Humanos , Proteínas de Unión a Poli(A)/metabolismo , Unión Proteica , Multimerización de Proteína , ARN Mensajero/metabolismo
2.
Sensors (Basel) ; 24(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38610590

RESUMEN

Indoor fires may cause casualties and property damage, so it is important to develop a system that predicts fires in advance. There have been studies to predict potential fires using sensor values, and they mostly exploited machine learning models or recurrent neural networks. In this paper, we propose a stack of Transformer encoders for fire prediction using multiple sensors. Our model takes the time-series values collected from the sensors as input, and predicts the potential fire based on the sequential patterns underlying the time-series data. We compared our model with traditional machine learning models and recurrent neural networks on two datasets. For a simple dataset, we found that the machine learning models are better than ours, whereas our model gave better performance for a complex dataset. This implies that our model has a greater potential for real-world applications that probably have complex patterns and scenarios.

3.
BMC Infect Dis ; 23(1): 32, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658559

RESUMEN

BACKGROUND: Nontuberculous mycobacterial lung disease (NTM-LD) and Mycobacterium tuberculosis lung disease (MTB-LD) have similar clinical characteristics. Therefore, NTM-LD is sometimes incorrectly diagnosed with MTB-LD and treated incorrectly. To solve these difficulties, we aimed to distinguish the two diseases in chest X-ray images using deep learning technology, which has been used in various fields recently. METHODS: We retrospectively collected chest X-ray images from 3314 patients infected with Mycobacterium tuberculosis (MTB) or nontuberculosis mycobacterium (NTM). After selecting the data according to the diagnostic criteria, various experiments were conducted to create the optimal deep learning model. A performance comparison was performed with the radiologist. Additionally, the model performance was verified using newly collected MTB-LD and NTM-LD patient data. RESULTS: Among the implemented deep learning models, the ensemble model combining EfficientNet B4 and ResNet 50 performed the best in the test data. Also, the ensemble model outperformed the radiologist on all evaluation metrics. In addition, the accuracy of the ensemble model was 0.85 for MTB-LD and 0.78 for NTM-LD on an additional validation dataset consisting of newly collected patients. CONCLUSIONS: In previous studies, it was known that it was difficult to distinguish between MTB-LD and NTM-LD in chest X-ray images, but we have successfully distinguished the two diseases using deep learning methods. This study has the potential to aid clinical decisions if the two diseases need to be differentiated.


Asunto(s)
Enfermedades Pulmonares , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium tuberculosis , Neumonía , Humanos , Estudios Retrospectivos , Rayos X , Infecciones por Mycobacterium no Tuberculosas/diagnóstico por imagen , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Micobacterias no Tuberculosas , Aprendizaje Automático
4.
Clin Oral Implants Res ; 34(2): 95-104, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36336985

RESUMEN

OBJECTIVES: The objective of the study was to evaluate the radiographic changes in sinus mucosal thickness (SMT) in patients with mucosal thickening of odontogenic origin after maxillary molar extraction and lateral sinus augmentation with simultaneous surgical drainage and implant placement. MATERIALS AND METHODS: Forty-six patients were included in this study. The changes in SMT were evaluated using cone-beam computed tomography images produced at four time points: before extraction (T0), before surgery (T1), immediately after surgery (T2), and after prosthesis delivery (T3), and statistical differences between time points were analyzed. The changes in SMT and augmented bone height (ABH) regarding the reason of extraction, smoking, ostial patency, and the presence of postoperative sinusitis were also evaluated. RESULTS: Over time points, SMT gradually decreased (T0: 19.44 ± 9.22 mm, T1: 15.10 ± 8.89 mm, T2: 8.42 ± 6.01 mm, and T3: 4.16 ± 4.91 mm) (p < .05). Five out of 6 patients with ostial obstruction at T1 presented ostial patency at T3. Two patients developed postoperative sinusitis but recovered with medication. Ostial patency at T1, SMT at T1, and reason of extraction did not statistically significantly influence SMT at T3. SMT at T1 had no statistically significant impact on ABH change between T2 and T3. CONCLUSION: Sinus mucosal thickness was gradually reduced by extraction of compromised teeth and drainage during lateral sinus augmentation. The drainage contributed more to the reduction in SMT.


Asunto(s)
Elevación del Piso del Seno Maxilar , Sinusitis , Senos Transversos , Humanos , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Elevación del Piso del Seno Maxilar/métodos , Extracción Dental , Tomografía Computarizada de Haz Cónico/métodos , Drenaje
5.
Eur Spine J ; 32(8): 2700-2708, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36917301

RESUMEN

PURPOSES: To analyze the clinical and radiographic risk factors that might predict incomplete clinical improvement after transforaminal endoscopic lumbar discectomy (TELD). METHODS: A retrospective analysis was conducted from 194 consecutive patients who underwent TELD due to lumbar disc herniation (LDH). Patients with incomplete clinical improvement were defined from patient-reported outcomes of poor improvement in pain or disability after surgery and patient dissatisfaction. Clinical and radiographic characteristics were evaluated to identify predicting factors of poor outcomes. RESULTS: Of 194 patients who underwent TELD procedures, 32 patients (16.5%) had incomplete clinical improvement and 12 patients (6.1%) required revision surgery. The mean ages were 46.4 years and most of the patients suffered from predominant leg pain (48.9%). The most common surgical level was L4-5 (63.9%). Overall, the Oswestry Disability Index (44.3-15), visual analog scores of back pain (4.9-1.8) and leg pain (7.3-1.6) were significantly improved after surgery. Multivariate logistic regression analysis demonstrated that high body mass index, history of previous surgery, preoperative disability, weakness, and disc degeneration were related to incomplete clinical improvement. There were 15 recurrent LDH (7.7%) with a total of 12 revision surgeries (6.2%). CONCLUSIONS: We identified independent risk factors associated with incomplete clinical improvement following TELD, including overweight, significant preoperative disability or weakness and history of previous surgery. Advanced age, disc degeneration, vacuum phenomenon, and spondylolisthesis were also possible risk factors. Recognizing these risk factors would help decide whether patients are good candidates for TELD, and optimize the surgical planning preoperatively to achieve good surgical results.


Asunto(s)
Discectomía Percutánea , Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral , Humanos , Persona de Mediana Edad , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/etiología , Degeneración del Disco Intervertebral/cirugía , Estudios Retrospectivos , Discectomía Percutánea/métodos , Resultado del Tratamiento , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Endoscopía/métodos , Discectomía/métodos , Dolor de Espalda/etiología
6.
Eur Spine J ; 32(8): 2808-2818, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36920512

RESUMEN

PURPOSE: The primary purpose of this study was to determine radiation exposure of the surgeon during transforaminal endoscopic lumbar foraminotomy (TELF). Secondary purpose of this study was to compare clinical and radiologic outcomes between TELF under C-arm fluoroscopic guidance (C-TELF) and O-arm navigation-guided TELF (O-TELF). METHODS: The author reviewed patients' medical records who underwent TELF at our institute from June 2015 to November 2022. A total of 40 patients were included (18 patients with C-TELF and 22 with O-TELF). Basic demographic data were collected. Preoperative/postoperative visual analog scale (VAS) and Oswestry Disability Index (ODI) were recorded at the outpatient clinic. Radiologic features were compared on X-rays at each follow-up. The degree of foraminal expansion was measured/compared through MRI. In the C-TELF group, the amount of exposure was calculated with a dosimeter. RESULTS: Average surgeon's effective dose in the C-TELF group was 0.036 mSv. In the case of the O-TELF group, there was no radiation exposure during operation. However, the operation time in the O-TELF group was about 37 min longer than that in the C-TELF group. There were significant improvements in VAS/ODI after operation in both groups. Complications were identified in three patients. CONCLUSION: O-TELF showed similarly favorable clinical and radiologic outcomes to C-TELF in lumbar foraminal stenosis, including complication rate. Compared to C-TELF, O-TELF has an advantage of not wearing a lead apron since the operator is not exposed to radiation. However, the operation time was longer with O-TELF due to O-arm setting time. Because there are pros and cons, the choice of surgical method depends on the surgeon's preference.


Asunto(s)
Foraminotomía , Cirugía Asistida por Computador , Humanos , Foraminotomía/métodos , Imagenología Tridimensional , Cirugía Asistida por Computador/métodos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Resultado del Tratamiento
7.
Eur Spine J ; 32(8): 2875-2881, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37029807

RESUMEN

INTRODUCTION: Endoscopic techniques are becoming popular among spine surgeons because of their advantages. Though the advantages of endoscopic spine surgery are evident and patients can be discharged home within hours of surgery, readmissions can be sought for incomplete relief of leg pain, recurrent disc herniation, and recurrent leg pain. We aim to find out the factors related to the readmission of patients treated for lumbar pathologies. MATERIALS AND METHODS: This is a retrospective analysis of the data between the time duration of 2012 and 2022. Patients in the age group of 18-85 years, with lumbar disc herniation treated by transforaminal endoscopic lumbar procedures, were included. The patients who were readmitted within 90 days were included in the R Group and those who were not were included in the NR group. Univariable and multivariable logistic regression analyses were used to find the risk factors for 90-day readmission. RESULTS: There were a total of 1542 patients enrolled in this study. Sex, number of episodes before admission, hypertension, smoking, BMI, migration, disc height, disc height index, spondylolisthesis, instability, pelvic tilt (PT), and disc cross-sectional area (CSA) were found significant on univariable analysis. Age, spondylolisthesis, instability and muscle CSA were the only variables that were found to be statistically significant on multivariable analysis. CONCLUSIONS: This study shows that the elderly age group, presence of spondylolisthesis, segmental instability and decreased muscle cross-sectional area are independent risk factors for 90-day hospital readmissions. Patients having the above risk factors should be carefully counseled regarding the possibility of readmission in the future.


Asunto(s)
Discectomía , Desplazamiento del Disco Intervertebral , Vértebras Lumbares , Readmisión del Paciente , República de Corea/epidemiología , Factores de Riesgo , Readmisión del Paciente/estadística & datos numéricos , Vértebras Lumbares/cirugía , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Endoscopía/estadística & datos numéricos , Discectomía/estadística & datos numéricos , Desplazamiento del Disco Intervertebral/epidemiología , Dolor
8.
J Korean Med Sci ; 38(19): e145, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37191848

RESUMEN

BACKGROUND: Low-density lipoprotein cholesterol is an important marker highly associated with cardiovascular disease. Since the direct measurement of it is inefficient in terms of cost and time, it is common to estimate through the Friedewald equation developed about 50 years ago. However, various limitations exist since the Friedewald equation was not designed for Koreans. This study proposes a new low-density lipoprotein cholesterol estimation equation for South Koreans using nationally approved statistical data. METHODS: This study used data from the Korean National Health and Nutrition Examination Survey from 2009 to 2019. The 18,837 subjects were used to develop the equation for estimating low-density lipoprotein cholesterol. The subjects included individuals with low-density lipoprotein cholesterol levels directly measured among those with high-density lipoprotein cholesterol, triglycerides, and total cholesterol measured. We compared twelve equations developed in the previous studies and the newly proposed equation (model 1) developed in this study with the actual low-density lipoprotein cholesterol value in various ways. RESULTS: The low-density lipoprotein cholesterol value estimated using the estimation formula and the actual low-density lipoprotein cholesterol value were compared using the root mean squared error. When the triglyceride level was less than 400 mg/dL, the root mean squared of the model 1 was 7.96, the lowest compared to other equations, and the model 2 was 7.82. The degree of misclassification was checked according to the NECP ATP III 6 categories. As a result, the misclassification rate of the model 1 was the lowest at 18.9%, and Weighted Kappa was the highest at 0.919 (0.003), which means it significantly reduced the underestimation rate shown in other existing estimation equations. Root mean square error was also compared according to the change in triglycerides level. As the triglycerides level increased, the root mean square error showed an increasing trend in all equations, but it was confirmed that the model 1 was the lowest compared to other equations. CONCLUSION: The newly proposed low-density lipoprotein cholesterol estimation equation showed significantly improved performance compared to the 12 existing estimation equations. The use of representative samples and external verification is required for more sophisticated estimates in the future.


Asunto(s)
Enfermedades Cardiovasculares , Humanos , LDL-Colesterol , Encuestas Nutricionales , Triglicéridos , HDL-Colesterol
9.
Sensors (Basel) ; 23(24)2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38139652

RESUMEN

The explosive demand for wireless communications has intensified the complexity of spectrum dynamics, particularly within unlicensed bands. To promote efficient spectrum utilization and minimize interference during communication, spectrum sensing needs to evolve to a stage capable of detecting multidimensional spectrum states. Signal identification, which identifies each device's signal source, is a potent method for deriving the spectrum usage characteristics of wireless devices. However, most existing signal identification methods mainly focus on signal classification or modulation classification, thus offering limited spectrum information. In this paper, we propose DSINet, a multitask learning-based deep signal identification network for advanced spectrum sensing systems. DSINet addresses the deep signal identification problem, which involves not only classifying signals but also deriving the spectrum usage characteristics of signals across various spectrum dimensions, including time, frequency, power, and code. Comparative analyses reveal that DSINet outperforms existing shallow signal identification models, with performance improvements of 3.3% for signal classification, 3.3% for hall detection, and 5.7% for modulation classification. In addition, DSINet solves four different tasks with a 65.5% smaller model size and 230% improved computational performance compared to single-task learning model sets, providing meaningful results in terms of practical use.

10.
Sensors (Basel) ; 23(14)2023 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-37514548

RESUMEN

We present a phase-locked synthetic wavelength interferometer that enables a complete elimination of cyclic errors in absolute distance measurements. With this method, the phase difference between the reference and measurement paths is fed back into a phase lock-in system, which is then used to control the synthetic wavelength and set the phase difference to zero using an external cavity acousto-optic modulator. We validated the cyclic error removal of the proposed phase-locked method by comparing it with the conventional phase-measuring method of the synthetic wavelength interferometer. By analyzing the locked error signal, we achieved a precision of 0.6 mrad in phase without any observed cyclic errors.

11.
Sensors (Basel) ; 23(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37960648

RESUMEN

We configured a long-distance ranging apparatus to test the principle of dual-comb time-of-flight measurement using ultrashort lasers. Emphasis was given to the evaluation of open-air performance quantitatively in terms of the measurement resolution and stability. The test results revealed that our dual-comb asynchronous optical pulse sampling permits micrometer-resolved ranging with a repeatability of 2.05 µm over a 648 m distance in dry weather conditions. Further atmospheric effects were evaluated in three different weather conditions with corresponding Allan deviations. Finally, the capability of simultaneous determination of multiple targets was verified with the potential of advanced industrial applications, such as manufacturing, surveying, metrology, and geodesy.

12.
Small ; 18(39): e2203126, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36026538

RESUMEN

Synthesis and coating of multi-metal oxides (MMOs) and alloys on conductive substrates are indispensable to electrochemical applications, yet demand multiple, resource-intensive, and time-consuming processes. Herein, an alternative approach to the synthesis and coating of alloys and MMOs by femtosecond laser direct writing (FsLDW) is reported. A solution-based precursor ink is deposited and dried on the substrate and illuminated by a femtosecond laser. During the illumination, dried precursor ink is transformed to MMO/alloys and is simultaneously bonded to the substrate. The formulation of the alloy and MMO precursor ink for laser processing is universally applicable to a large family of oxides and alloys. The process is conducted at room temperature and in an open atmosphere. To demonstrate, a large family of 57 MMOs and alloys are synthesized from a group of 13 elements. As a proof of concept, Ni0.24 Co0.23 Cu0.24 Fe0.15 Cr0.14 high entropy alloy synthesized on stainless-steel foil by FsLDW is used for the oxygen evolution reaction, which achieves a current density of 10 mA cm-2 at a significantly low overpotential of 213 mV. Further, FsLDW can also achieve microfabrication of alloys/MMO with feature sizes down to 20 µm.

13.
Plant Biotechnol J ; 20(12): 2298-2312, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36062974

RESUMEN

The ongoing coronavirus disease 2019 (COVID-19) pandemic has spurred rapid development of vaccines as part of the public health response. However, the general strategy used to construct recombinant trimeric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) proteins in mammalian cells is not completely adaptive to molecular farming. Therefore, we generated several constructs of recombinant S proteins for high expression in Nicotiana benthamiana. Intramuscular injection of N. benthamiana-expressed Sct vaccine (NSct Vac) into Balb/c mice elicited both humoral and cellular immune responses, and booster doses increased neutralizing antibody titres. In human angiotensin-converting enzyme knock-in mice, two doses of NSct Vac induced anti-S and neutralizing antibodies, which cross-neutralized Alpha, Beta, Delta and Omicron variants. Survival rates after lethal challenge with SARS-CoV-2 were up to 80%, without significant body weight loss, and viral titres in lung tissue fell rapidly, with no infectious virus detectable at 7-day post-infection. Thus, plant-derived NSct Vac could be a candidate COVID-19 vaccine.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Ratones , Animales , Humanos , Nicotiana/genética , SARS-CoV-2 , COVID-19/prevención & control , Adyuvantes Inmunológicos , Ratones Endogámicos BALB C , Anticuerpos Neutralizantes , Inmunidad , Mamíferos
14.
Macromol Rapid Commun ; 43(7): e2100686, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35084074

RESUMEN

Interest in resistive random access memory (RRAM) has grown rapidly in recent years for realizing ultrahigh density data storage devices. However, sneak currents in these devices can result in misreading of the data, thus limiting the applicability of RRAM. Complementary resistive switching (CRS) memory consisting of two antiserial RRAMs can considerably reduce sneak currents; however, complicated device architectures and manufacturing processes still remain as challenges. Herein, an effective and simple approach for fabricating CRS memory devices using self-assembled block copolymer micelles is reported. Cu ions are selectively placed in the core of polystyrene-block-poly(2-vinylpyridine) spherical micelles, and a hexagonally packed micelle monolayer is prepared through spin-coating. The micelle monolayer can be a symmetrical resistive switching layer, because the micelles and Cu act as dielectric and active metals in memory devices, respectively. The locally enhanced electric field and Joule heating achieved by the structured Cu atoms inside the micelles promote metal ionization and ion migration in a controlled manner, thus allowing for position selectivity during resistive switching. The micelle-based memory device exhibits stable and reliable CRS behavior, with a nonoverlapping and narrow distribution of threshold voltages. Therefore, this approach is promising for fabricating CRS memory devices for high-performance and ultrahigh-density RRAM applications.

15.
Nucleic Acids Res ; 48(6): 3328-3342, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32002546

RESUMEN

Monoubiquitination of the Fanconi anemia complementation group D2 (FANCD2) protein by the FA core ubiquitin ligase complex is the central event in the FA pathway. FANCA and FANCG play major roles in the nuclear localization of the FA core complex. Mutations of these two genes are the most frequently observed genetic alterations in FA patients, and most point mutations in FANCA are clustered in the C-terminal domain (CTD). To understand the basis of the FA-associated FANCA mutations, we determined the cryo-electron microscopy (EM) structures of Xenopus laevis FANCA alone at 3.35 Å and 3.46 Å resolution and two distinct FANCA-FANCG complexes at 4.59 and 4.84 Å resolution, respectively. The FANCA CTD adopts an arc-shaped solenoid structure that forms a pseudo-symmetric dimer through its outer surface. FA- and cancer-associated point mutations are widely distributed over the CTD. The two different complex structures capture independent interactions of FANCG with either FANCA C-terminal HEAT repeats, or the N-terminal region. We show that mutations that disturb either of these two interactions prevent the nuclear localization of FANCA, thereby leading to an FA pathway defect. The structure provides insights into the function of FANCA CTD, and provides a framework for understanding FA- and cancer-associated mutations.


Asunto(s)
Proteína del Grupo de Complementación A de la Anemia de Fanconi/ultraestructura , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/ultraestructura , Proteína del Grupo de Complementación G de la Anemia de Fanconi/ultraestructura , Anemia de Fanconi/genética , Animales , Núcleo Celular/genética , Núcleo Celular/ultraestructura , Microscopía por Crioelectrón , Cristalografía por Rayos X , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/ultraestructura , Anemia de Fanconi/patología , Proteína del Grupo de Complementación A de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación G de la Anemia de Fanconi/química , Humanos , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Mutación , Unión Proteica/genética , Conformación Proteica , Xenopus laevis/genética
16.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35162958

RESUMEN

The development of nerve conduits with a three-dimensional porous structure has attracted great attention as they closely mimic the major features of the natural extracellular matrix of the nerve tissue. As low levels of reactive oxygen species (ROS) function as signaling molecules to promote cell proliferation and growth, this study aimed to fabricate protoporphyrin IX (PpIX)-immobilized cellulose (CEPP) monoliths as a means to both guide and stimulate nerve regeneration. CEPP monoliths can be fabricated via a simple thermally induced phase separation method and surface modification. The improved nerve tissue regeneration of CEPP monoliths was achieved by the activation of mitogen-activated protein kinases, such as extracellular signal-regulated kinases (ERKs). The resulting CEPP monoliths exhibited interconnected microporous structures and uniform morphology. The results of in vitro bioactivity assays demonstrated that the CEPP monoliths with under 0.54 ± 0.07 µmol/g PpIX exhibited enhanced photodynamic activity on Schwann cells via the generation of low levels of ROS. This photodynamic activation of the CEPP monoliths is a cell-safe process to stimulate cell proliferation without cytotoxic side effects. In addition, the protein expression of phospho-ERK increased considerably after the laser irradiation on the CEPP monoliths with low content of PpIX. Therefore, the CEPP monoliths have a potential application in nerve tissue regeneration as new nerve conduits.


Asunto(s)
Celulosa/química , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Protoporfirinas/farmacología , Células de Schwann/citología , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/efectos de la radiación , Terapia por Luz de Baja Intensidad , Regeneración Nerviosa , Tejido Nervioso/química , Fosforilación , Protoporfirinas/química , Ratas , Especies Reactivas de Oxígeno/metabolismo , Células de Schwann/efectos de los fármacos , Células de Schwann/metabolismo , Células de Schwann/efectos de la radiación
17.
Korean J Parasitol ; 60(1): 51-56, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35247955

RESUMEN

Global efforts to identify groups at high risk for schistosomiasis have mainly concentrated on identifying their geographical distribution. Investigations on the socioeconomic characteristics of high-risk groups are relatively scarce. This study aimed to explore the associations between schistosomiasis among students and their parents' occupations. A nationwide cross-sectional survey was conducted targeting 105,167 students in 1,772 primary schools across Sudan in 2017. From these students, 100,726 urine and 96,634 stool samples were collected to test for Schistosoma haematobium and S. mansoni infection. A multi-level mixed effect analysis was used with age and sex as fixed factors, and school as a random factor. The odd ratios (ORs) of practicing open defecation among farmers' children were almost 5 times higher than their counterparts whose parents were government officials (OR=4.97, 95% confidence intervals (CIs): 4.57-5.42, P<0.001). The ORs of contacting water bodies for watering livestock among farmers' children were more than 4 times higher than those of children whose parents were government officials (OR=4.59, 95% CIs: 4.02-5.24, P<0.001). This study shows that schistosomiasis represents a disease of poverty and that farmers' children constituted a high-risk group.


Asunto(s)
Esquistosomiasis Urinaria , Esquistosomiasis mansoni , Animales , Niño , Estudios Transversales , Heces , Humanos , Ocupaciones , Padres , Prevalencia , Schistosoma haematobium , Esquistosomiasis Urinaria/epidemiología , Esquistosomiasis mansoni/epidemiología , Estudiantes , Sudán/epidemiología
18.
Small ; 17(51): e2102772, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34622562

RESUMEN

Repetitious mechanical stress or external mechanical impact can damage wearable electronic devices, leading to serious degradations in their electrical performances, which limits their applications. Because self-healing would be an excellent solution to the above-mentioned issue, this paper presents a self-healable memory device based on a novel nanocomposite layer consisting of a polyvinyl alcohol matrix and imidazole-modified graphene quantum dots. The device exhibits reliable electrical performance over 600 cycles, and the electrical properties of the device are maintained without any failure under this bending stress. Further, it is confirmed that the damaged device can recover its original electric characteristics after the self-healing process. It is believed that such outstanding results will lead the way to the realization of future wearable electronic systems.


Asunto(s)
Grafito , Nanocompuestos , Conductividad Eléctrica , Imidazoles , Alcohol Polivinílico
19.
Nanotechnology ; 32(27)2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33780921

RESUMEN

Photodynamic therapy (PDT) has been extensively explored as a promising alternative therapeutic approach for many malignant tumors. However, the PDT system generally involves unsatisfactory tumor specificity and nonspecific accumulation of photosensitizers around the target cancer cells, leading to phototoxic damage to adjacent healthy normal cells. In this study, we developed pheophorbide a (Pheo a)/human epidermal growth factor receptor 2 (HER2) targeting peptide (epitope form, HLTV, PEG2-LTVSPWY)-co-conjugated methoxy poly(ethylene glycol)-block-poly(L-lysine hydrochloride) (PEG-PLL)/hyaluronic acid (HA) (P3H2) polymeric micelles via a self-assembly method for HER2-targeted PDT treatment for breast cancer, thereby enhancing the PDT efficacy. The synthesized P3H2 polymeric micelles were spherical, with an average diameter of 125.7 ± 21.2 nm in an aqueous solution. The results ofin vitrocytotoxicity assays demonstrated that the P3H2 polymeric micelles significantly improved PDT efficacy on the SK-BR-3 cells due to the enhanced targeting ability. In addition, PDT treatment using the P3H2 polymeric micelles effectively killed breast cancer cells by inducing higher intracellular reactive oxygen species generation and apoptotic cell death. In particular, the three-dimensional cell culture model proved the synergistic PDT efficacy using P3H2 polymeric micelles on the SK-BR-3 cells. Based on these results, the PDT treatment using P3H2 polymeric micelles can serve as a highly effective therapeutic modality for breast cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Micelas , Fármacos Fotosensibilizantes/farmacología , Receptor ErbB-2/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofila/análogos & derivados , Clorofila/química , Clorofila/farmacología , Clorofila/uso terapéutico , Femenino , Humanos , Ácido Hialurónico/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico , Polietilenglicoles/química , Polilisina/química
20.
Nanotechnology ; 32(4): 045201, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33032272

RESUMEN

Notwithstanding its excellent properties such as high work function and low resistance, Ru has not been widely applied in the preparation of electrodes for various electronic devices. This is because of the occurrence of severe morphological degradation in the actual devices employing Ru. Herein, we investigated Ru chemistry for electrode application and the degradation mechanism of Ru during subsequent processes such as thin film deposition or thermal annealing. We revealed that subsurface oxygen induces Ru degradation owing to the alteration of Ru chemistry by the pretreatment under various gas ambient conditions and due to the growth behavior of TiO2 deposited via atomic layer deposition (ALD). The degradation of Ru is successfully ameliorated by conducting an appropriate pretreatment prior to ALD. The TiO2 thin film deposited on the pretreated Ru electrode exhibited a rutile-phased crystal structure and smooth surface morphology, thereby resulting in excellent electrical properties. This paper presents an important development in the application of Ru as the electrode that can facilitate the development of various next-generation electronic devices.

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