Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 210
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Int J Med Sci ; 21(4): 644-655, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38464836

RESUMEN

Vascular dementia (VD) is the second most prevalent dementia type, with no drugs approved for its treatment. Here, the effects of Banhabaekchulcheonma-Tang (BBCT) on ischemic brain injury and cognitive function impairment were investigated in a bilateral carotid artery stenosis (BCAS) mouse model. Mice were divided into sham-operated, BCAS control, L-BBCT (40 ml/kg), and H-BBCT (80 ml/kg) groups. BBCT's effects were characterized using the Y-maze test, novel object recognition test (NORT), immunofluorescence staining, RNA sequencing, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analyses. The NORT revealed cognitive function improvement in the H-BBCT group, while the Y-maze test revealed no significant difference among the four groups. The CD68+ microglia and GFAP+ astrocyte numbers were reduced in the H-BBCT group. Furthermore, H-BBCT treatment restored the dysregulation of gene expression caused by BCAS. The major BBCT targets were predicted to be cell division cycle protein 20 (CDC20), Epidermal growth factor (EGF), and tumor necrosis factor receptor-associated factor 1 (TRAF1). BBCT regulates the neuroactive ligand-receptor interaction and neuropeptide signaling pathways, as predicted by KEGG and GO analyses, respectively. BBCT significantly improved cognitive impairment in a BCAS mouse model by inhibiting microglial and astrocyte activation and regulating the expression of CDC20, EGF, TRAF1, and key proteins in the neuroactive ligand-receptor interaction and neuropeptide signaling pathways.


Asunto(s)
Lesiones Encefálicas , Isquemia Encefálica , Estenosis Carotídea , Disfunción Cognitiva , Neuropéptidos , Animales , Ratones , Estenosis Carotídea/complicaciones , Estenosis Carotídea/tratamiento farmacológico , Factor de Crecimiento Epidérmico/metabolismo , Ligandos , Factor 1 Asociado a Receptor de TNF/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/etiología , Cognición , Modelos Animales de Enfermedad , Neuropéptidos/metabolismo , Ratones Endogámicos C57BL
2.
Eur Spine J ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38878173

RESUMEN

PURPOSE: To evaluate the actual change in clinical hip pain and hip migration after operation for non-ambulatory flaccid neuromuscular (NM) scoliosis and investigate whether there is an association between hip migration and coronal/sagittal pelvic tilt (CO-PT/SA-PT). PATIENTS AND METHODS: This retrospective, single-center, observational study evaluated a total of 134 patients with non-ambulatory flaccid neuromuscular scoliosis who underwent surgery performed by a single surgeon between 2003 and 2020, with at least 2 years of follow-up period. Operation procedures were conducted in two stages, beginning with L5-S1 anterior release followed by posterior fixation. Radiologic parameters were measured at preoperative, immediate postoperative, and last follow-up periods with clinical hip pain and clinical hip dislocation events. RESULTS: The significant improvements occurred in various parameters after correction surgery for NM scoliosis, containing Cobb's angle of major curve and CO-PT. However, Reimer's hip migration percentage (RMP) was increased on both side of hip (High side, 0.23 ± 0.16 to 0.28 ± 0.21; Low side, 0.20 ± 0.14 to 0.23 ± 0.18). Hip pain and dislocation events were also increased (Visual analog scale score, 2.5 ± 2.3 to 3.6 ± 2.6, P value < 0.05; dislocation, 6-12). Logistic regression analysis of the interactions between ΔRMP(High) and the change of sagittal pelvic tilt (ΔSA-PT) after correction reveals a significant negative association. (95% CI 1.003-1.045, P value = 0.0226). CONCLUSIONS: In cases of non-ambulatory flaccid NM scoliosis, clinical hip pain, and subluxation continued to deteriorate even after correction of CO-PT. There was a relationship between the decrease in SA-PT, and an increase in hip migration percentage on high side, indicating the aggravation of hip subluxation.

3.
Nature ; 550(7677): 524-528, 2017 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-29045386

RESUMEN

Sphingosine-1-phosphate (S1P), a potent signalling lipid secreted by red blood cells and platelets, plays numerous biologically significant roles. However, the identity of its long-sought exporter is enigmatic. Here we show that the major facilitator superfamily transporter 2b (Mfsd2b), an orphan transporter, is essential for S1P export from red blood cells and platelets. Comprehensive lipidomic analysis indicates a dramatic and specific accumulation of S1P species in Mfsd2b knockout red blood cells and platelets compared with that of wild-type controls. Consistently, biochemical assays from knockout red blood cells, platelets, and cell lines overexpressing human and mouse Mfsd2b proteins demonstrate that Mfsd2b actively exports S1P. Plasma S1P level in knockout mice is significantly reduced by 42-54% of that of wild-type level, indicating that Mfsd2b pathway contributes approximately half of the plasma S1P pool. The reduction of plasma S1P in knockout mice is insufficient to cause blood vessel leakiness, but it does render the mice more sensitive to anaphylactic shock. Stress-induced erythropoiesis significantly increased plasma S1P levels and knockout mice were sensitive to these treatments. Surprisingly, knockout mice exhibited haemolysis associated with red blood cell stomatocytes, and the haemolytic phenotype was severely increased with signs of membrane fragility under stress erythropoiesis. We show that S1P secretion by Mfsd2b is critical for red blood cell morphology. Our data reveal an unexpected physiological role of red blood cells in sphingolipid metabolism in circulation. These findings open new avenues for investigating the signalling roles of S1P derived from red blood cells and platelets.


Asunto(s)
Plaquetas/metabolismo , Eritrocitos/metabolismo , Lisofosfolípidos/metabolismo , Proteínas de la Membrana/metabolismo , Esfingosina/análogos & derivados , Anemia/genética , Anemia/metabolismo , Animales , Transporte Biológico , Forma de la Célula , Recuento de Eritrocitos , Eritrocitos/citología , Eliminación de Gen , Células HEK293 , Humanos , Lisofosfolípidos/sangre , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Esfingosina/sangre , Esfingosina/metabolismo
4.
BMC Public Health ; 23(1): 1232, 2023 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-37365542

RESUMEN

BACKGROUND: The term, "multiple chronic diseases" (MCD), describes a patient with two or more chronic conditions simultaneously at the same time. Compared with general chronic diseases, it is linked to poorer health outcomes, more difficult clinical management, and higher medical expenses. Several existing MCD guidelines support a healthy lifestyle including regular physical activities but do not include specific exercise therapy recommendations. This study aimed to understand the prevalence and model of MCD in middle-aged and elderly South Koreans by comparing MCD characteristics with exercise habits, to provide a theoretical basis for the implementation of exercise therapy in these patients. METHODS: The data of 8477 participants aged > 45 years from the "2020 Korean Health Panel Survey" were used to analyze the current status of MCD in the middle-aged and elderly. The Chi-square test for categorical variables and the t-test for continuous variables. the used software was IBM SPSS Statistics 26.0 and IBM SPSS Modeler 18.0. RESULTS: In this study, the morbidity rate of MCD was 39.1%. Those with MCD were more likely to be female (p < 0.001), seniors over 65 years of age (p < 0.001), with low education level, no regular exercise behavior (p < 0.01). Chronic renal failure (93.9%), depression (90.4%), and cerebrovascular disease (89.6%) were the top three diseases identified in patients with MCD. A total of 37 association rules were identified for the group of individuals who did not engage in regular exercise. This equated to 61% more than that of the regular exercise group, who showed only 23 association rules. In the extra association rules, cardiovascular diseases (150%), spondylosis (143%), and diabetes (125%) are the three chronic diseases with the highest frequency increase. CONCLUSIONS: Association rule analysis is effective in studying the relationship between various chronic diseases in patients with MCD. It also effectively helps with the identification of chronic diseases that are more sensitive to regular exercise behaviors. The findings from this study may be used to formulate more appropriate and scientific exercise therapy for patients with MCD.


Asunto(s)
Pueblos del Este de Asia , Afecciones Crónicas Múltiples , Anciano , Persona de Mediana Edad , Humanos , Femenino , Masculino , Ejercicio Físico , Enfermedad Crónica , Hábitos , Algoritmos
5.
Osteoporos Int ; 33(11): 2409-2416, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35925259

RESUMEN

In this retrospective study, the effectiveness of short-term teriparatide with denosumab in reducing fragility fracture risk was determined in comparison with denosumab monotherapy. Administration of sequential teriparatide with denosumab showed excellent outcomes in suppressing the risk for fragility fractures compared with denosumab monotherapy. INTRODUCTION: To determine the effectiveness of short-term teriparatide with denosumab in reducing the risk of fragility fractures in comparison to denosumab monotherapy. METHODS: The data of postmenopausal patients treated with denosumab for > 2 years between August 2015 and October 2020 were retrospectively analyzed. One hundred sixty four postmenopausal women of a total 615 were excluded, since they did not undergo > 2 bone mineral density (BMD) tests, were lost to follow-up, or received long-term teriparatide therapy. Total 320 patients received denosumab monotherapy and 131 patients received teriparatide for ≥ 3 months followed by denosumab. The number of osteoporotic fractures, presence of back pain before and after treatment, and annual BMD during treatment were comparatively assessed using t-test, Chi-square test, and linear mixed model analysis. RESULTS: Before treatment, the denosumab monotherapy group had fewer osteoporotic fractures (mean ± standard deviation; 0.459 ± 0.689) than the sequential therapy group had (1.037 ± 0.871; p < 0.001). After treatment, the sequential therapy group had fewer osteoporotic fractures than the denosumab monotherapy group had (0.119 ± 0.348 versus 0.144 ± 0.385; p < 0.001). At 1 and 2 years after treatment, the increase in lumbar spine BMD was greater in the sequential therapy group than in the denosumab monotherapy group (p = 0.08, group × time). The difference between post and pre-treatment back pain visual analog scale score was significantly lower in the sequential therapy group than in the monotherapy group (3.246 ± 3.426 versus 1.734 ± 3.049; p < 0.001). CONCLUSION: Short-term teriparatide use before denosumab showed excellent outcomes in suppressing the risk of fragility fractures compared with denosumab monotherapy.


Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis Posmenopáusica , Fracturas Osteoporóticas , Densidad Ósea , Denosumab/uso terapéutico , Femenino , Humanos , Osteoporosis Posmenopáusica/inducido químicamente , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/inducido químicamente , Fracturas Osteoporóticas/prevención & control , Estudios Retrospectivos , Teriparatido
6.
Ann Hepatol ; 27(4): 100709, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35489641

RESUMEN

INTRODUCTION AND AIM: Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases in the United States. Metabolic distress (obese diabetes) is the main causative element of NAFLD. While there is no cure for NAFLD, endurance exercise (EEx) has emerged as a therapeutic strategy against NAFLD. However, mechanisms of EXE-induced hepatic protection especially in female subjects remain unidentified. Thus, the aim of the study is to examine molecular mechanisms of EXE-induced hepatic protection against diet-induced NAFLD in female mice. MATERIAL AND METHODS: Nine-week-old female C57BL/6J mice were randomly divided into three groups: normal-diet control group (CON, n=11); high-fat diet/high-fructose group (HFD/HF, n=11); and HFD/HF+EEx group (HFD/HF+EEx, n=11). The mice assigned to HFD/HF and HFD/HF+EEx groups were fed with HFD/HF for 12 weeks, after which the mice assigned to the EEx group began treadmill exercise for 12 weeks, with HFD/HF continued. RESULTS: EEx attenuated hepatic steatosis, reduced de novo lipogenesis (reduction in ATP-Citrate- Lyase and diacylglycerol-O-acyltransferase 1), and enhanced mitochondrial biogenesis and fatty-acid activation (oxidative phosphorylation enzymes and Acyl-CoA synthetase1). Also, EEx prevented upregulation of gluconeogenic proteins (glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phosphatase, and phosphoenolpyruvate-carboxykinase1), premature senescence (suppression of p53, p22, and p16, tumor-necrosis-factor-α, and interleukin-1ß, and oxidative stress), and autophagy deficiency. Furthermore, EXE reversed apoptosis arrest (cleaved cysteine-dependent-aspartate-directed protease3 and Poly-(ADP-ribose)-polymerase1). CONCLUSION: EEx-mediated reparations of metabolic and redox imbalance (utilization of pentose phosphate pathway), and autophagy deficiency caused by metabolic distress critically contribute to preventing/delaying severe progression of NAFLD. Also, EEx-induced anti-senescence and cell turnover are crucial protective mechanisms against NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Humanos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/prevención & control
7.
Sensors (Basel) ; 22(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408128

RESUMEN

As an alternative to traditional remote controller, research on vision-based hand gesture recognition is being actively conducted in the field of interaction between human and unmanned aerial vehicle (UAV). However, vision-based gesture system has a challenging problem in recognizing the motion of dynamic gesture because it is difficult to estimate the pose of multi-dimensional hand gestures in 2D images. This leads to complex algorithms, including tracking in addition to detection, to recognize dynamic gestures, but they are not suitable for human-UAV interaction (HUI) systems that require safe design with high real-time performance. Therefore, in this paper, we propose a hybrid hand gesture system that combines an inertial measurement unit (IMU)-based motion capture system and a vision-based gesture system to increase real-time performance. First, IMU-based commands and vision-based commands are divided according to whether drone operation commands are continuously input. Second, IMU-based control commands are intuitively mapped to allow the UAV to move in the same direction by utilizing estimated orientation sensed by a thumb-mounted micro-IMU, and vision-based control commands are mapped with hand's appearance through real-time object detection. The proposed system is verified in a simulation environment through efficiency evaluation with dynamic gestures of the existing vision-based system in addition to usability comparison with traditional joystick controller conducted for applicants with no experience in manipulation. As a result, it proves that it is a safer and more intuitive HUI design with a 0.089 ms processing speed and average lap time that takes about 19 s less than the joystick controller. In other words, it shows that it is viable as an alternative to existing HUI.


Asunto(s)
Algoritmos , Gestos , Mano , Humanos , Movimiento (Física) , Reconocimiento en Psicología , Extremidad Superior
8.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36366070

RESUMEN

The rapid development of deep-learning-based edge artificial intelligence applications and their data-driven nature has led to several research issues. One key issue is the collaboration of the edge and cloud to optimize such applications by increasing inference speed and reducing latency. Some researchers have focused on simulations that verify that a collaborative edge-cloud network would be optimal, but the real-world implementation is not considered. Most researchers focus on the accuracy of the detection and recognition algorithm but not the inference speed in actual deployment. Others have implemented such networks with minimal pressure on the cloud node, thus defeating the purpose of an edge-cloud collaboration. In this study, we propose a method to increase inference speed and reduce latency by implementing a real-time face recognition system in which all face detection tasks are handled on the edge device and by forwarding cropped face images that are significantly smaller than the whole video frame, while face recognition tasks are processed at the cloud. In this system, both devices communicate using the TCP/IP protocol of wireless communication. Our experiment is executed using a Jetson Nano GPU board and a PC as the cloud. This framework is studied in terms of the frame-per-second (FPS) rate. We further compare our framework using two scenarios in which face detection and recognition tasks are deployed on the (1) edge and (2) cloud. The experimental results show that combining the edge and cloud is an effective way to accelerate the inferencing process because the maximum FPS achieved by the edge-cloud deployment was 1.91× more than the cloud deployment and 8.5× more than the edge deployment.


Asunto(s)
Inteligencia Artificial , Reconocimiento Facial , Algoritmos , Sistemas de Computación
9.
Sensors (Basel) ; 22(23)2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36502225

RESUMEN

Facial emotion recognition (FER) systems are imperative in recent advanced artificial intelligence (AI) applications to realize better human-computer interactions. Most deep learning-based FER systems have issues with low accuracy and high resource requirements, especially when deployed on edge devices with limited computing resources and memory. To tackle these problems, a lightweight FER system, called Light-FER, is proposed in this paper, which is obtained from the Xception model through model compression. First, pruning is performed during the network training to remove the less important connections within the architecture of Xception. Second, the model is quantized to half-precision format, which could significantly reduce its memory consumption. Third, different deep learning compilers performing several advanced optimization techniques are benchmarked to further accelerate the inference speed of the FER system. Lastly, to experimentally demonstrate the objectives of the proposed system on edge devices, Light-FER is deployed on NVIDIA Jetson Nano.


Asunto(s)
Reconocimiento Facial , Humanos , Expresión Facial , Emociones , Inteligencia Artificial
10.
Hum Factors ; : 187208211064707, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35344676

RESUMEN

OBJECTIVE: The study aimed to provide a comprehensive overview of the factors impacting technology adoption, to predict the acceptance of artificial intelligence (AI)-based technologies. BACKGROUND: Although the acceptance of AI devices is usually defined by behavioural factors in theories of user acceptance, the effects of technical and human factors are often overlooked. However, research shows that user behaviour can vary depending on a system's technical characteristics and differences in users. METHOD: A systematic review was conducted. A total of 85 peer-reviewed journal articles that met the inclusion criteria and provided information on the factors influencing the adoption of AI devices were selected for the analysis. RESULTS: Research on the adoption of AI devices shows that users' attitudes, trust and perceptions about the technology can be improved by increasing transparency, compatibility, and reliability, and simplifying tasks. Moreover, technological factors are also important for reducing issues related to human factors (e.g. distrust, scepticism, inexperience) and supporting users with lower intention to use and lower trust in AI-infused systems. CONCLUSION: As prior research has confirmed the interrelationship among factors with and without behaviour theories, this review suggests extending the technology acceptance model that integrates the factors studied in this review to define the acceptance of AI devices across different application areas. However, further research is needed to collect more data and validate the study's findings. APPLICATION: A comprehensive overview of factors influencing the acceptance of AI devices could help researchers and practitioners evaluate user behaviour when adopting new technologies.

11.
J Am Chem Soc ; 143(15): 5836-5844, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33834782

RESUMEN

The identification of each cell type is essential for understanding multicellular communities. Antibodies set as biomarkers have been the main toolbox for cell-type recognition, and chemical probes are emerging surrogates. Herein we report the first small-molecule probe, CDgB, to discriminate B lymphocytes from T lymphocytes, which was previously impossible without the help of antibodies. Through the study of the origin of cell specificity, we discovered an unexpected novel mechanism of membrane-oriented live-cell distinction. B cells maintain higher flexibility in their cell membrane than T cells and accumulate the lipid-like probe CDgB more preferably. Because B and T cells share common ancestors, we tracked the cell membrane changes of the progenitor cells and disclosed the dynamic reorganization of the membrane properties over the lymphocyte differentiation progress. This study casts an orthogonal strategy for the small-molecule cell identifier and enriches the toolbox for live-cell distinction from complex cell communities.


Asunto(s)
Linfocitos B/citología , Membrana Celular/metabolismo , Colorantes Fluorescentes/química , Linfocitos T/citología , Animales , Linfocitos B/química , Linfocitos B/inmunología , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Diferenciación Celular , Membrana Celular/química , Citometría de Flujo , Lipidómica , Ratones , Linfocitos T/química , Linfocitos T/inmunología
12.
Sensors (Basel) ; 21(13)2021 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-34283138

RESUMEN

OBJECTIVE: The purpose of this study was to verify changes in a driver's emotions through the physical characteristics of haptic signals. This is to improve the performance of drivers by designing haptic signals with emotional semantics. BACKGROUND: Currently, drivers receive a variety of information through intelligent systems installed in their vehicles. Because this is mainly achieved through visual and auditory channels, an excessive amount of information is provided to drivers, which increases the amount of information and cognitive load that they must accept. This, in turn, can reduce driving safety. It is, therefore, necessary to develop a haptic signal, a sensory channel that has not been widely used in in-vehicle information systems. METHODS: The experiment was performed to collect a driver's emotions according to the haptic signal in a driving simulator. Haptic signals were designed by various frequencies and accelerations, and driver emotions were collected through Kansei engineering techniques and analyzed through factor analysis. To verify intelligibility, haptic signals were compared and evaluated based on response time, response rate, and amount of transmitted information. RESULTS: The final determined emotional map consisted of dangerousness and urgency. Based on the emotional map, four emotional semantic haptic signals were designed. It was confirmed that these four signals displayed higher performance than the discriminability haptic signal in terms of response time, response rate, and amount of transmitted information. CONCLUSIONS: Using emotional maps, it is possible to design haptic signals that can be applied to various driving situations. These maps may also assist in securing design guidelines for haptic signals that apply to in-vehicle information systems.


Asunto(s)
Conducción de Automóvil , Aceleración , Accidentes de Tránsito , Cognición , Sistemas de Información , Tiempo de Reacción
13.
J Therm Biol ; 99: 103017, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34420645

RESUMEN

The present study was conducted to investigate the impact of a 42 d period of heat stress on laying hens with respect to rectal temperature, body-surface temperature, heart rate, heterophil to lymphocyte ratio (H/L ratio), corticosterone (CORT) in plasma and yolk samples, and video-assessed behaviors. A total of one hundred twenty 56-week-old ISA-brown laying hens were continuously exposed to one of three temperature regimes: optimal (LT; 22 °C), moderate (MT; 27 °C), and high (HT; 32 °C). The relative humidity was maintained at 50% in all treatments. HT vs. MT and LT increased rectal temperature, heart rate, and body-surface temperature on all days (P < 0.05). HT vs. LT raised (P < 0.05) the H/L ratio in blood at day 42 following heat exposure. On the other hand, both HT- and MT-exposed laying hens had higher (P < 0.05) plasma CORT compared with those on LT group only at 28 and 42 d following heat treatment. Yolk CORT was elevated (P < 0.05) in the HT vs. MT and LT groups at 3 and 14 d following heat treatment. Panting and wing elevation were the most relevant behaviors in laying hens exposed to HT vs. MT and LT. The study shows that rectal and body-surface temperature, heart rate, and behavior, but not CORT or H/L ratio, are the reliable indicators for assessing the stress status of laying hens over extended period of heat stress.


Asunto(s)
Pollos/fisiología , Respuesta al Choque Térmico , Animales , Conducta Animal , Temperatura Corporal , Pollos/sangre , Femenino , Calor , Hidrocortisona/sangre
14.
Microcirculation ; 27(7): e12649, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32663357

RESUMEN

PURPOSE: Impaired red blood cell (RBC) deformability impedes tissue perfusion. This study aims to investigate RBC biomechanics in type 2 diabetes mellitus (DM) patients with different grades of diabetic retinopathy (DR) and to correlate RBC deformability with hematological and serum biochemical markers. METHODS: This cross-sectional study included 86 type 2 DM patients (31 with no DR, 31 with non-proliferative DR [NPDR] and 24 with proliferative DR [PDR]) and 32 control subjects. RBC deformability was measured by a microfluidic cross-slot channel (elongation index, EI). Venous blood samples were taken for assessment of hematological and serum biochemical markers. RESULTS: RBC deformability showed significant reduction in diabetic patients, being lowest in the PDR group, followed by NPDR and DM with no DR groups, and highest in control group (P = .018). RBC deformability was not affected by age or gender but showed significant associations with certain hematological and serum biochemical markers. In the regression analysis controlling for DM status, urea concentration and reticulocyte count were shown to be negatively associated with EI. CONCLUSION: Impaired RBC deformability measured by a microfluidic cross-slot channel in DM patients with different grades of DR underscores the contribution of RBC rheological properties to the pathogenesis and progression of DM related microangiopathy.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Retinopatía Diabética/sangre , Deformación Eritrocítica/fisiología , Adulto , Anciano , Biomarcadores/sangre , Fenómenos Biomecánicos , Estudios de Casos y Controles , Estudios Transversales , Retinopatía Diabética/clasificación , Retinopatía Diabética/etiología , Recuento de Eritrocitos , Femenino , Humanos , Masculino , Técnicas Analíticas Microfluídicas , Persona de Mediana Edad , Modelos Biológicos , Reticulocitos , Urea/sangre
15.
Artif Organs ; 44(12): e520-e531, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32698240

RESUMEN

In a healthy human cardiac system, a large asymmetric clockwise vortex present in the left ventricle (LV) efficiently diverts the filling jet from the mitral annulus to the left ventricular outflow track. However, prior clinical studies have shown that artificial mitral valve replacement can affect the formation of physiological vortex, resulting in overall flow instability in the LV. Lately, the findings from several recent hemodynamic studies seem to suggest that the native D-shaped mitral annulus might be a crucial factor in the development of this physiological flow pattern, with its inherent flow stability and formation of coherent structures within the LV. This study aims to investigate the effect of orifice shape and its position with respect to the posterior wall of the ventricle on vortical formation and turbulence intensity in the LV, by utilizing four separate orifice configurations within an in vitro left heart simulator. Stereo particle image velocimetry experiments were then carried out to characterize the downstream flow field of each configuration. Our findings demonstrate that the generation of the physiological left ventricular vortical flow was not solely dependent upon the orifice shape but rather the subsequent jet-wall interaction. The distance of the orifice geometric center from the left ventricular posterior wall plays a significant role in this jet-wall interaction, and thus, vortical flow dynamics.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas/efectos adversos , Válvula Mitral/fisiología , Modelos Cardiovasculares , Diseño de Prótesis , Velocidad del Flujo Sanguíneo/fisiología , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Hemorreología , Humanos , Válvula Mitral/cirugía , Función Ventricular Izquierda/fisiología
16.
Sensors (Basel) ; 20(21)2020 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33171796

RESUMEN

This study presents a computational method called economical auto moment limiter (eAML) that prevents a mobile cargo crane from being overloaded. The eAML detects and controls, in real time, crane overload without using boom stroke sensors and load cells, which are expensive items inevitable to existing AML systems, hence, being competitive in price. It replaces these stroke sensors and load cells that are used for the crane overload measurement with a set of mathematical formula and control logics that calculates the lifting load being handled under crane operation and the maximum lifting load. By calculating iterative them using only a pressure sensor attached under the derrick cylinder and the boom angle sensor, the mathematical model identifies the maximum descendible angle of the boom. The control logic presents the control method for preventing the crane overload by using the descendible angle obtained by the mathematical model. Both the mathematical model and the control logic are validated by rigorous simulation experiments using MATLAB on two case instances each of which eAML is used and not used, while changing the pressures on the derrick cylinder and the boom angle. The effectiveness and validity of the method are confirmed by comparing the outputs obtained by the controlled experiments performed by using a 7.6 ton crane on top of SCS887 and a straight-type maritime heavy-duty crane along with eAML. The effects attributed to the load and the wind speed are quantified to verify the reliability of eAML under the changes in external variables.

17.
J Nanosci Nanotechnol ; 19(7): 3854-3858, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30764943

RESUMEN

Zinc oxide (ZnO) is a commonly used material for the front contact layer of thin film solar cells based on chalcopyrite CuInGaSe2 (CIGS), since it satisfies the optical and electrical properties with low cost and is abundantly available. For high-performance, the front contact electrode in the CIGS solar cell should have low resistivity and high transmittance. Hence, efforts to improve ZnO's electrical and optical properties have been widely carried out. The corrosion resistance of the front contact film, however, has not been studied well. So, this paper compared the electrochemical stability of ZnO based transparent conducting oxide (TCO) films such as aluminum zinc oxide (AZO), gallium zinc oxide (GZO) and aluminum gallium zinc oxide (AGZO) grown in H2. All films predominately grew in the (002) c-axis direction and their crystallites improved with increasing H2 ratio, reflecting the enhanced electrical properties. Hydrogen acts as a shallow donor in the n-type ZnO semiconductor and increases carrier densities by forming oxygen vacancies by combining with oxygen molecules to form OH- functionalities. The electrochemical corrosion resistance of prepared films showed a linear improvement with increasing hydrogen. This change was attributed to the grain morphology and size and resulting grain boundaries. Since corrosion occurs mainly at grain boundaries, corrosion resistance seems to be better with a lower density of grain boundaries, due to larger grains caused by hydrogen. Electric conductivity was better in the order of GZO > AGZO > AZO, while corrosion resistance was in the reverse order. By adding hydrogen, the electrical resistivity of AGZO improved to near GZO, and the corrosion resistance was also enhanced to near AZO.

18.
BMC Vet Res ; 14(1): 152, 2018 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-29720166

RESUMEN

BACKGROUND: Sodium pentosan polysulfate (NaPPS) was testified as a chondroprotective drug in with a detailed rationale of the disease-modifying activity. This study was undertaken to determine whether anti-osteoarthritis drug, NaPPS inhibited osteoclasts (OC) differentiation and function. Canine bone marrow mononuclear cells (n = 6) were differentiated to OC by maintaining with receptor activator of nuclear factor kappa B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) for up to 7 days with the treatment of NaPPS at concentration of 0, 0.2, 1 and 5 µg/mL. Differentiation and function of OC were accessed using tartrate-resistant acid phosphate (TRAP) staining and bone resorption assay, while monitoring actin ring formation. Invasion and colocalization patterns of fluorescence-labeled NaPPS with transcribed gene in OC were monitored. Gene expression of OC for cathepsin K (CTK), matrix metallopeptidase-9 (MMP-9), nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), c-Fos, activator protein-1(AP-1) and carbonic anhydrase II was examined using real-time PCR. RESULTS: Significant inhibition of OC differentiation was evident at NaPPS concentration of 1 and 5 µg/mL (p < 0.05). In the presence of 0.2 to 5 µg/mL NaPPS, bone resorption was attenuated (p < 0.05), while 1 and 5 µg/mL NaPPS achieved significant reduction of actin ring formation. Intriguingly, fluorescence-labeled NaPPS invaded in to cytoplasm and nucleus while colocalizing with actively transcribed gene. Gene expression of CTK, MMP-9 and NFATc1 were significantly inhibited at 1 and 5 µg/mL (p < 0.05) of NaPPS whereas inhibition of c-Fos and AP-1 was identified only at concentration of 5 µg/mL (p < 0.05). CONCLUSIONS: Taken together, all the results suggest that NaPPS is a novel inhibitor of RANKL and M-CSF-induced CTK, MMP-9, NFATc1, c-Fos, AP-1 upregulation, OC differentiation and bone resorption which might be a beneficial for treatment of inflammatory joint diseases and other bone diseases associated with excessive bone resorption.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Poliéster Pentosan Sulfúrico/farmacología , Actinas/metabolismo , Animales , Células Cultivadas , Perros , Humanos , Factor Estimulante de Colonias de Macrófagos/metabolismo , Osteoclastos/citología , Ligando RANK/metabolismo , Factores de Transcripción/antagonistas & inhibidores
19.
J Nanosci Nanotechnol ; 18(3): 1995-2000, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29448698

RESUMEN

Rapid macroscopic-scale assembly of Ag nanowires was demonstrated through facile self-assembly at the water/air interface. This self-assembly was induced by heating due to the surface tension effect and convection. Interestingly, a rippled hairstyle superstructure was observed when the aqueous dispersions of thinner Ag nanowires were heated. Applying the Euler buckling theory for a set of aligned Ag nanowires, it was found that the water surface tension was sufficient to bend or buckle these free Ag nanowires trapped between two nanowire stripes, which resulted in the formation of the rippled hairstyle superstructure. However, the formation of the nanowire stripes was driven by steric repulsion of nanowires along with their short-range van der Waals interactions and later lateral capillary attraction between large building blocks. Such control over self-assembly is key for designing hierarchically ordered structures, which opens a new opportunity in the exploration of novel properties and the development of new applications.

20.
Mar Drugs ; 15(6)2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28617322

RESUMEN

The protective effects of a chondroitin sulfate-rich extract (CSE) from skate cartilage against lipopolysaccharide (LPS)-induced hepatic damage were investigated, and its mechanism of action was compared with that of chondroitin sulfate (CS) from shark cartilage. ICR mice were orally administrated 200 mg/kg body weight (BW) of CS or 400 mg/kg BW of CSE for 3 consecutive days, followed by a one-time intraperitoneal injection of LPS (20 mg/kg BW). The experimental groups were vehicle treatment without LPS injection (NC group), vehicle treatment with LPS injection (LPS group), CS pretreatment with LPS injection (CS group), and CSE pretreatment with LPS injection (CSE group). Hepatic antioxidant enzyme expression levels in the CS and CSE groups were increased relative to those in the LPS group. In LPS-insulted hepatic tissue, inflammatory factors were augmented relative to those in the NC group, but were significantly suppressed by pretreatment with CS or CSE. Moreover, CS and CSE alleviated the LPS-induced apoptotic factors and mitogen-activated protein kinase (MAPK). In addition, CS and CSE effectively decreased the serum lipid concentrations and downregulated hepatic sterol regulatory element-binding proteins expression. In conclusion, the skate CSE could protect against LPS-induced hepatic dyslipidemia, oxidative stress, inflammation, and apoptosis, probably through the regulation of MAPK signaling.


Asunto(s)
Cartílago/química , Sulfatos de Condroitina/farmacología , Lipopolisacáridos/toxicidad , Hígado/efectos de los fármacos , Rajidae , Animales , Peso Corporal/efectos de los fármacos , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos ICR , Factor de Necrosis Tumoral alfa/análisis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA