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1.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37050567

RESUMEN

In this study, the design of a Digital-twin human-machine interface sensor (DT-HMIS) is proposed. This is a digital-twin sensor (DT-Sensor) that can meet the demands of human-machine automation collaboration in Industry 5.0. The DT-HMIS allows users/patients to add, modify, delete, query, and restore their previously memorized DT finger gesture mapping model and programmable logic controller (PLC) logic program, enabling the operation or access of the programmable controller input-output (I/O) interface and achieving the extended limb collaboration capability of users/patients. The system has two main functions: the first is gesture-encoded virtual manipulation, which indirectly accesses the PLC through the DT mapping model to complete control of electronic peripherals for extension-limbs ability by executing logic control program instructions. The second is gesture-based virtual manipulation to help non-verbal individuals create special verbal sentences through gesture commands to improve their expression ability. The design method uses primitive image processing and eight-way dual-bit signal processing algorithms to capture the movement of human finger gestures and convert them into digital signals. The system service maps control instructions by observing the digital signals of the DT-HMIS and drives motion control through mechatronics integration or speech synthesis feedback to express the operation requirements of inconvenient work or complex handheld physical tools. Based on the human-machine interface sensor of DT computer vision, it can reflect the user's command status without the need for additional wearable devices and promote interaction with the virtual world. When used for patients, the system ensures that the user's virtual control is mapped to physical device control, providing the convenience of independent operation while reducing caregiver fatigue. This study shows that the recognition accuracy can reach 99%, demonstrating practicality and application prospects. In future applications, users/patients can interact virtually with other peripheral devices through the DT-HMIS to meet their own interaction needs and promote industry progress.


Asunto(s)
Gestos , Dispositivos Electrónicos Vestibles , Humanos , Interfaz Usuario-Computador , Dedos , Algoritmos
2.
Front Robot AI ; 9: 808154, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35546901

RESUMEN

Evaluating the dexterity of human and robotic hands through appropriate benchmarks, scores, and metrics is of paramount importance for determining how skillful humans are and for designing and developing new bioinspired or even biomimetic end-effectors (e.g., robotic grippers and hands). Dexterity tests have been used in industrial and medical settings to assess how dexterous the hands of workers and surgeons are as well as in robotic rehabilitation settings to determine the improvement or deterioration of the hand function after a stroke or a surgery. In robotics, having a comprehensive dexterity test can allow us to evaluate and compare grippers and hands irrespectively of their design characteristics. However, there is a lack of well defined metrics, benchmarks, and tests that quantify robot dexterity. Previous work has focused on a number of widely accepted functional tests that are used for the evaluation of manual dexterity and human hand function improvement post injury. Each of these tests focuses on a different set of specific tasks and objects. Deriving from these tests, this work proposes a new modular, affordable, accessible, open-source dexterity test for both humans and robots. This test evaluates the grasping and manipulation capabilities by combining the features and best practices of the aforementioned tests, as well as new task categories specifically designed to evaluate dexterous manipulation capabilities. The dexterity test and the accompanying benchmarks allow us to determine the overall hand function recovery and dexterity of robotic end-effectors with ease. More precisely, a dexterity score that ranges from 0 (simplistic, non-dexterous system) to 1 (human-like system) is calculated using the weighted sum of the accuracy and task execution speed subscores. It should also be noted that the dexterity of a robotic system can be evaluated assessing the efficiency of either the robotic hardware, or the robotic perception system, or both. The test and the benchmarks proposed in the study have been validated using extensive human and robot trials. The human trials have been used to determine the baseline scores for the evaluation system. The results show that the time required to complete the tasks reduces significantly with trials indicating a clear learning curve in mastering the dexterous manipulation capabilities associated with the imposed tasks. Finally, the time required to complete the tasks with restricted tactile feedback is significantly higher indicating its importance.

3.
J Hazard Mater ; 416: 125856, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492805

RESUMEN

Inhalation of aerosols such as pharmaceutical aerosols or virus aerosol uptake is of great concern to the human population. To elucidate the underlying aerosol dynamics, the deposition fractions (DFs) of aerosols in healthy and asthmatic human airways of generations 13-15 are predicted. The Navier-stokes equations governing the gaseous phase and the discrete phase model for particles' motion are solved using numerical methods. The main forces responsible for deposition are inertial impaction forces and complex secondary flow velocities. The curvatures and sinusoidal folds in the asthmatic geometry lead to the formation of complex secondary flows and hence higher DFs. The intensities of complex secondary flows are strongest at the generations affected by asthma. The DF in the healthy airways is 0%, and it ranges from 1.69% to 52.93% in the asthmatic ones. From this study, the effects of the pharmaceutical aerosol particle diameters in the treatment of asthma patients can be established, which is conducive to inhibiting the inflammation of asthma airways. Furthermore, with the recent development of COVID-19 which causes pneumonia, the predicted physics and effective simulation methods of bioaerosols delivery to asthma patients are vital to prevent the exacerbation of the chronic ailment and the epidemic.


Asunto(s)
Asma , COVID-19 , Aerosoles , Asma/tratamiento farmacológico , Simulación por Computador , Humanos , Pulmón , Modelos Biológicos , Tamaño de la Partícula , SARS-CoV-2
4.
Sensors (Basel) ; 21(8)2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33924090

RESUMEN

Electricity is a vital resource for various human activities, supporting customers' lifestyles in today's modern technologically driven society. Effective demand-side management (DSM) can alleviate ever-increasing electricity demands that arise from customers in downstream sectors of a smart grid. Compared with the traditional means of energy management systems, non-intrusive appliance load monitoring (NIALM) monitors relevant electrical appliances in a non-intrusive manner. Fog (edge) computing addresses the need to capture, process and analyze data generated and gathered by Internet of Things (IoT) end devices, and is an advanced IoT paradigm for applications in which resources, such as computing capability, of a central data center acted as cloud computing are placed at the edge of the network. The literature leaves NIALM developed over fog-cloud computing and conducted as part of a home energy management system (HEMS). In this study, a Smart HEMS prototype based on Tridium's Niagara Framework® has been established over fog (edge)-cloud computing, where NIALM as an IoT application in energy management has also been investigated in the framework. The SHEMS prototype established over fog-cloud computing in this study utilizes an artificial neural network-based NIALM approach to non-intrusively monitor relevant electrical appliances without an intrusive deployment of plug-load power meters (smart plugs), where a two-stage NIALM approach is completed. The core entity of the SHEMS prototype is based on a compact, cognitive, embedded IoT controller that connects IoT end devices, such as sensors and meters, and serves as a gateway in a smart house/smart building for residential DSM. As demonstrated and reported in this study, the established SHEMS prototype using the investigated two-stage NIALM approach is feasible and usable.

5.
World J Clin Cases ; 9(5): 1148-1155, 2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33644179

RESUMEN

BACKGROUND: In the development of coronary stent technology, bioresorbable scaffolds are promising milestones in improving the clinical treatment of coronary artery disease. The "leave nothing behind" motto is the premise of the fourth revolution in percutaneous coronary intervention (PCI). Studies proving the safety and efficacy of the magnesium-based resorbable scaffolds (MgBRSs) include the BIOSOLVE-I and BIOSOLVE-II trials and the latest BIOSOLVE-IV registry. However, spontaneous retrograde dissection of a partially absorbed MgBRS may still occur, albeit rarely. CASE SUMMARY: We describe an unusual case of coronary artery disease in a patient who had undergone a successful PCI 8 mo earlier, where an MgBRS was implanted into the left anterior descending artery (LAD) and left circumflex artery with drug-coated balloons for a ramus intermedius branch stenosis to achieve the "leave nothing behind" therapeutic intention and was currently presenting with a gradual worsening of chest tightness. The distal edge vascular response, during subsequent attempts with balloon angioplasty was performed smoothly. However, spontaneous retrograde dissection of a partially absorbed MgBRS in the LAD ensued. Successful bailout stenting was performed with revascularization of the entry and exit sites created by spontaneous dissection and complete sealing of the intramural hematoma. The patient recovered well and was discharged after 2 d of intervention. When followed up in August 2020 (7 mo later), the patient showed uneventful recovery. CONCLUSION: Spontaneous retrograde dissection of a partially absorbed MgBRS was successfully treated using bailout sirolimus-eluting coronary stent strategy.

6.
Environ Res ; 197: 110975, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33689824

RESUMEN

The deposition phenomenon of microparticle and SAR-CoV-2 laced bioaerosol in human airways is studied by Taguchi methods and response surface methodology (RSM). The data used herein is obtained from simulations of airflow dynamics and deposition fractions of drug particle aerosols in the downstream airways of asthma patients using computational fluid dynamics (CFD) and discrete particle motion (DPM). Three main parameters, including airflow rate, drug dose, and particle size, affecting aerosol deposition in the lungs of asthma patients are examined. The highest deposition fraction (DF) is obtained at the flow rate of 45 L min-1, the drug dose of 200 µg·puff-1, and the particle diameter of 5 µm. The optimized combination of levels for the three parameters for maximum drug deposition is performed via the Taguchi method. The importance of the influencing factors rank as particle size > drug dose > flow rate. RSM reveals that the combination of 30 L min-1, 5 µm, 200 µg·puff- has the highest deposition fraction. In part, this research also studied the deposition of bioaerosols contaminated with the SAR-CoV-2 virus, and their lowest DF is 1.15%. The low DF of bioaerosols reduces the probability of the SAR-CoV-2 virus transmission.


Asunto(s)
Hidrodinámica , Pulmón , Administración por Inhalación , Aerosoles , Simulación por Computador , Humanos , Modelos Biológicos , Tamaño de la Partícula
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4775-4778, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33019058

RESUMEN

The performance and safety of human robot interaction (HRI) can be improved by using subject-specific movement prediction. Typical models include biomechanical (parametric) or black-box (non-parametric) models. The current work aims to investigate the benefits and drawbacks of these approaches by comparing elbow-joint torque predictions based on electromyography signals of the elbow flexors and extensors. To this end, a parameterized biomechanical model is compared to a non-parametric (Gaussian-process) approach. Both models showed adequate results in predicting the elbow-joint torques. While the non-parametric model requires minimal modeling effort, the parameterized biomechanical model can lead to deeper insight of the underlying subject specific musculoskeletal system.


Asunto(s)
Articulación del Codo , Movimiento , Codo , Electromiografía , Humanos , Torque
8.
Front Robot AI ; 7: 601274, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33501363

RESUMEN

Traditionally, the robotic end-effectors that are employed in unstructured and dynamic environments are rigid and their operation requires sophisticated sensing elements and complicated control algorithms in order to handle and manipulate delicate and fragile objects. Over the last decade, considerable research effort has been put into the development of adaptive, under-actuated, soft robots that facilitate robust interactions with dynamic environments. In this paper, we present soft, retractable, pneumatically actuated, telescopic actuators that facilitate the efficient execution of stable grasps involving a plethora of everyday life objects. The efficiency of the proposed actuators is validated by employing them in two different soft and hybrid robotic grippers. The hybrid gripper uses three rigid fingers to accomplish the execution of all the tasks required by a traditional robotic gripper, while three inflatable, telescopic fingers provide soft interaction with objects. This synergistic combination of soft and rigid structures allows the gripper to cage/trap and firmly hold heavy and irregular objects. The second, simplistic and highly affordable robotic gripper employs just the telescopic actuators, exhibiting an adaptive behavior during the execution of stable grasps of fragile and delicate objects. The experiments demonstrate that both grippers can successfully and stably grasp a wide range of objects, being able to exert significantly high contact forces.

9.
Front Neurorobot ; 13: 91, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31787889

RESUMEN

Adaptive robot hands are typically created by introducing structural compliance either in their joints (e.g., implementation of flexures joints) or in their finger-pads. In this paper, we present a series of alternative uses of structural compliance for the development of simple, adaptive, compliant and/or under-actuated robot grippers and hands that can efficiently and robustly execute a variety of grasping and dexterous, in-hand manipulation tasks. The proposed designs utilize only one actuator per finger to control multiple degrees of freedom and they retain the superior grasping capabilities of the adaptive grasping mechanisms even under significant object pose or other environmental uncertainties. More specifically, in this work, we introduce, discuss, and evaluate: (a) a design of pre-shaped, compliant robot fingers that adapts/conforms to the object geometry, (b) a hyper-adaptive finger-pad design that maximizes the area of the contact patches between the hand and the object, maximizing also grasp stability, and (c) a design that executes compliance adjustable manipulation tasks that can be predetermined by tuning the in-series compliance of the tendon routing system and by appropriately selecting the imposed tendon loads. The grippers are experimentally tested and their efficiency is validated using three different types of tests: (i) grasping tests that involve different everyday objects, (ii) grasp quality tests that estimate the contact area between the grippers and the objects grasped, and (iii) dexterous, in-hand manipulation experiments to evaluate the manipulation capabilities of the Compliance Adjustable Manipulation (CAM) hand. The devices employ mechanical adaptability to facilitate and simplify the efficient execution of robust grasping and dexterous, in-hand manipulation tasks.

10.
Sensors (Basel) ; 19(21)2019 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-31684178

RESUMEN

In this study, an innovative, ensemble learning method in a dynamic imaging system of an unmanned vehicle is presented. The feasibility of the system was tested in the crack detection of a retaining wall in a climbing area or a mountain road. The unmanned vehicle can provide a lightweight and remote cruise routine with a Geographic Information System sensor, a Gyro sensor, and a charge-coupled device camera. The crack was the target to be tested, and the retaining wall was patrolled through the drone flight path setting, and then the horizontal image was instantly returned by using the wireless transmission of the system. That is based on the cascade classifier, and the feature comparison classifier was designed further, and then the machine vision correlation algorithm was used to analyze the target type information. First, the system collects the target image and background to establish the samples database, and then uses the Local Binary Patterns feature extraction algorithm to extract the feature values for classification. When the first stage classification is completed, the classification results are target features, and edge feature comparisons. The innovative ensemble learning classifier was used to analyze the image and determine the location of the crack for risk assessment.

11.
Microb Cell Fact ; 13: 130, 2014 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-25201011

RESUMEN

The gene encoding the putative reductase component (KshB) of 3-ketosteroid 9α-hydroxylase was cloned from Rhodococcus equi USA-18, a cholesterol oxidase-producing strain formerly named Arthrobacter simplex USA-18, by PCR according to consensus amino acid motifs of several bacterial KshB subunits. Deletion of the gene in R. equi USA-18 by a PCR-targeted gene disruption method resulted in a mutant strain that could accumulate up to 0.58 mg/ml 1,4-androstadiene-3,17-dione (ADD) in the culture medium when 0.2% cholesterol was used as the carbon source, indicating the involvement of the deleted enzyme in 9α-hydroxylation of steroids. In addition, this mutant also accumulated 3-oxo-23,24-bisnorchola-1,4-dien-22-oic acid (Δ1,4-BNC). Because both ADD and Δ1,4-BNC are important intermediates for the synthesis of steroid drugs, this mutant derived from R. equi USA-18 may deserve further investigation for its application potential.


Asunto(s)
Androstadienos/metabolismo , Eliminación de Gen , Oxigenasas de Función Mixta/genética , Oxidorreductasas/genética , Rhodococcus equi/genética , Esteroides/química , Esteroles/metabolismo , Androstadienos/química , Biotransformación , Línea Celular , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Cromosomas Bacterianos/genética , Técnicas de Inactivación de Genes , Genes Bacterianos , Humanos , Macrófagos/microbiología , Espectrometría de Masas , Reacción en Cadena de la Polimerasa , Estándares de Referencia , Reproducibilidad de los Resultados , Rhodococcus equi/enzimología , Rhodococcus equi/crecimiento & desarrollo , Esteroides/metabolismo , Esteroles/química , Factores de Tiempo
12.
Biochim Biophys Acta ; 1838(6): 1529-35, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24468064

RESUMEN

Membrane fusion is essential for intracellular trafficking and virus infection, but the molecular mechanisms underlying the fusion process remain poorly understood. In this study, we employed all-atom molecular dynamics simulations to investigate the membrane fusion mechanism using vesicle models which were pre-bound by inter-vesicle Ca(2+)-lipid clusters to approximate Ca(2+)-catalyzed fusion. Our results show that the formation of the hemifusion diaphragm for vesicle fusion is a multi-step event. This result contrasts with the assumptions made in most continuum models. The neighboring hemifused states are separated by an energy barrier on the energy landscape. The hemifusion diaphragm is much thinner than the planar lipid bilayers. The thinning of the hemifusion diaphragm during its formation results in the opening of a fusion pore for vesicle fusion. This work provides new insights into the formation of the hemifusion diaphragm and thus increases understanding of the molecular mechanism of membrane fusion. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.


Asunto(s)
Membrana Dobles de Lípidos/química , Fusión de Membrana/fisiología , Simulación de Dinámica Molecular , Liposomas Unilamelares/metabolismo , Algoritmos , Calcio/química , Biología Computacional , Fluidez de la Membrana , Modelos Moleculares , Fosfatidiletanolaminas/química , Liposomas Unilamelares/química , Agua/química
13.
Acta Cardiol Sin ; 30(4): 274-83, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27122800

RESUMEN

BACKGROUND: Studies have reported that women with ST elevation myocardial infarction (STEMI) have worse short- and long-term outcomes than men. It has not yet been confirmed whether these differences reflect differences in age between men and women. METHODS: We retrospectively enrolled 1035 consecutive STEMI patients treated with primary percutaneous coronary intervention (PCI). Baseline clinical characteristics, coronary anatomy, and outcome were compared between young (< 65 years old) and older patients (≥ 65 years old) of both sexes. RESULTS: Younger women presented with a lower incidence of typical angina (83% vs. 93%, p = 0.03), single-vessel disease (21% vs. 35%, p = 0.03), and total occlusion of infarct-related artery (65% vs. 83%, p = 0.001) than younger men, with no gender difference noted in the older group. Younger women in the study had a higher incidence of reinfarction, heart failure requiring admission, or mortality (23% vs. 6%, p < 0.001) during follow-up, compared with younger men, with no gender difference in the older group. Using the Kaplan-Meier analysis, younger women had lower rates of event-free survival (p < 0.001 by log-rank test) than younger men, with no gender difference in the older group. In multivariate analysis, age could predict long-term outcome in men (Hazard ratio 4.43, 95% confidence interval: 2.89-6.78, p < 0.001) but not in women. CONCLUSIONS: In STEMI patients receiving primary PCI, sex-related long-term outcome differences were age-dependent, with younger women likely to have a worse long-term outcome when compared with younger men. KEY WORDS: Coronary heart disease; Gender; Myocardial infarction.

14.
Biochim Biophys Acta ; 1828(11): 2729-38, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23911761

RESUMEN

Although membrane fusion plays key roles in intracellular trafficking, neurotransmitter release, and viral infection, its underlying molecular mechanism and its energy landscape are not well understood. In this study, we employed all-atom molecular dynamics simulations to investigate the fusion mechanism, catalyzed by Ca(2+) ions, of two highly hydrated 1-palmitoyl-2-oleoyl-sn-3-phosphoethanolamine (POPE) micelles. This simulation system mimics the small contact zone between two large vesicles at which the fusion is initiated. Our simulations revealed that Ca(2+) ions are capable of catalyzing the fusion of POPE micelles; in contrast, we did not observe close contact of the two micelles in the presence of only Na(+) or Mg(2+) ions. Determining the free energy landscape of fusion allowed us to characterize the underlying molecular mechanism. The Ca(2+) ions play a key role in catalyzing the micelle fusion in three aspects: creating a more-hydrophobic surface on the micelles, binding two micelles together, and enhancing the formation of the pre-stalk state. In contrast, Na(+) or Mg(2+) ions have relatively limited effects. Effective fusion proceeds through sequential formation of pre-stalk, stalk, hemifused-like, and fused states. The pre-stalk state is the state featuring lipid tails exposed to the inter-micellar space; its formation is the rate-limiting step. The stalk state is the state where a localized hydrophobic core is formed connecting two micelles; its formation occurs in conjunction with water expulsion from the inter-micellar space. This study provides insight into the molecular mechanism of fusion from the points of view of energetics, structure, and dynamics.


Asunto(s)
Calcio/química , Fusión de Membrana , Micelas , Fosfolípidos/química , Catálisis , Interacciones Hidrofóbicas e Hidrofílicas , Simulación de Dinámica Molecular , Fosfatidiletanolaminas/química
15.
Acta Cardiol Sin ; 29(2): 151-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27122699

RESUMEN

PUPOSE: The newer 256-slice computed tomography coronary angiography (CTCA) has the capability of improving diagnostic performance in the detection of obstructive coronary artery disease (CAD) compared to 64-slice CTCA. The aim of this study was to compare the diagnostic performance of 64- versus 256-slice CTCA in two similar populations. METHODS: Our study included 120 consecutive patients who were referred for CTCA and subsequently underwent conventional coronary angiography (CCA). Sixty patients were studied by 64-slice CTCA, with the other 60 by 256-slice CTCA. We compared the technical characteristics and diagnostic performance of 64- and 256-slice CTCA for the detection of ≥ 50% stenosis of the coronary arteries on CCA. RESULTS: The 256-slice CTCA had a shorter scanning time (4.4 ± 0.6 sec vs. 5.0 ± 0.7 sec, p < 0.001) compared to 64-slice CTCA. The diagnostic accuracy rates of 256-slice CTCA based on patient analysis (97% vs. 83%, p < 0.05), vessel analysis (95% vs. 85%, p < 0.05), and segment analysis (94% vs. 88%, p < 0.05) were significantly superior to those of 64-slice CTCA. The diagnostic accuracy rates of 64- and 256-slice CTCA were affected by the presence of stent (65% vs. 75%, respectively, p > 0.05) and severe calcifications (75% vs. 82%, respectively, p > 0.05). CONCLUSIONS: In two similar populations, 256-slice CTCA displayed superior diagnostic performance than 64-slice CTCA. However, the performance of 256-slide CTCA is affected in those segments that are severely calcified and/or stented. KEY WORDS: Computed tomography coronary angiography (CTCA); Conventional coronary angiography; Diagnostic performance; 64-slice helical CTCA; 256-slice helical CTCA.

16.
Am J Crit Care ; 20(3): 218-25, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21532042

RESUMEN

BACKGROUND: Gastrointestinal bleeding is a hemorrhagic complication after primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction (STEMI). OBJECTIVES: To determine predictors of gastrointestinal bleeding and the impact of gastrointestinal bleeding on outcomes in STEMI patients undergoing primary percutaneous coronary intervention. METHODS AND RESULTS: Gastrointestinal bleeding occurred in 18 (3.5%) of 519 consecutive patients with STEMI undergoing primary percutaneous coronary intervention. Univariate predictors of gastrointestinal bleeding were previous gastrointestinal bleeding (33% vs 4%, P < .001), impaired renal function (89% vs 37%, P<.001), Killip class IV at presentation (61% vs 18%, P<.001), higher peak creatinine kinase level (mean [SD], 3801.6 [3280.2] vs 2721.3 [2286.6] IU/L, P=.05), and mechanical ventilator support (44% vs 12%, P<.001). Coprescription of proton-pump inhibitors did not reduce the risk of gastrointestinal bleeding (22.2% vs 13.4%, P=.22). Multivariate analysis showed an odds ratio (95% confidence interval) for gastrointestinal bleeding of 22.1 (5.6-86.89, P<.001) for previous gastrointestinal bleeding, 6.74 (1.30-34.89, P=.02) for impaired renal function, and 4.68 (1.35-16.2, P=.01) for Killip class IV at presentation. Gastrointestinal bleeding was associated with longer intensive care unit stay (mean [SD], 5.4 [6.7] vs 3.6 [3.6] days, P=.04), and higher in-hospital (44% vs 9%, P<.001) and overall (44% vs 13%, P<.001) mortality rate. CONCLUSIONS: Although rare, gastrointestinal bleeding in patients with STEMI significantly prolongs intensive care unit stay and increases mortality. Previous gastrointestinal bleeding, impaired renal function, and Killip class IV at presentation are associated with higher incidence of gastrointestinal bleeding.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Anticoagulantes/efectos adversos , Hemorragia Gastrointestinal/etiología , Infarto del Miocardio/terapia , Inhibidores de Agregación Plaquetaria/efectos adversos , Anticoagulantes/administración & dosificación , Aspirina/administración & dosificación , Aspirina/efectos adversos , Clopidogrel , Femenino , Hemorragia Gastrointestinal/mortalidad , Heparina/administración & dosificación , Heparina/efectos adversos , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/mortalidad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Estudios Retrospectivos , Factores de Riesgo , Taiwán , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos , Ticlopidina/análogos & derivados , Resultado del Tratamiento
17.
Heart Vessels ; 26(1): 101-10, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20978896

RESUMEN

Pulmonary veins (PVs) contain cardiomyocytes with a complex cellular morphology and high arrhythmogenesis. Ca(2+) regulation and Ca(2+) sparks play a pivotal role in the electrical activity of cardiomyocytes. The purpose of this study was to investigate whether the cell morphology can determine the PV electrical activity and Ca(2+) homeostasis. Through confocal microscopy with fluo-3 Ca(2+) fluorescence, Ca(2+) sparks and Ca(2+) transients were evaluated in isolated single rabbit left atria (LA) and PV cardiomyocytes according to the cell morphology (rod, rod-spindle and spindle/bifurcated). Twenty-two (20%) rod, 49 (43%) rod-spindle and 41 (37%) spindle/bifurcated cardiomyocytes were identified in the LA (n = 29) and PV (n = 83) cardiomyocytes. The PV cardiomyocytes with pacemaker activity had a higher incidence of spindle/bifurcated morphology than LA and PV cardiomyocytes without pacemaker activity. As compared to those in the rod or rod-spindle cardiomyocytes, spindle/bifurcated cardiomyocytes had a larger Ca(2+) transient amplitude and higher frequency of the Ca(2+) sparks with larger amplitude and longer duration. In contrast, rod-spindle and rod cardiomyocytes had similar Ca(2+) transients and Ca(2+) sparks. The cell length correlated well with the amplitude of the Ca(2+) transient and Ca(2+) spark duration with a linear regression. In conclusion, cell morphology and cell length play a potential role in the Ca(2+) homeostasis and Ca(2+) spark. The large Ca(2+) transients and high frequency of Ca(2+) sparks in spindle/bifurcated cardiomyocytes may cause a high arrhythmogenesis in the PV cardiomyocytes with pacemaker activity.


Asunto(s)
Relojes Biológicos , Señalización del Calcio , Forma de la Célula , Frecuencia Cardíaca , Miocitos Cardíacos/metabolismo , Venas Pulmonares/metabolismo , Análisis de Varianza , Animales , Atrios Cardíacos/citología , Atrios Cardíacos/metabolismo , Técnicas In Vitro , Potenciales de la Membrana , Microscopía Confocal , Venas Pulmonares/citología , Conejos , Factores de Tiempo
18.
J Formos Med Assoc ; 109(6): 430-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20610144

RESUMEN

BACKGROUND/PURPOSE: Knowledge concerning subacute stent thrombosis (SST) following primary stenting for ST-elevation myocardial infarction (STEMI) is not widely available. We studied the incidence, predictors, and clinical outcomes of SST following STEMI. METHODS: We analyzed data from 455 consecutive patients who underwent primary stenting for STEMI. Baseline clinical characteristics, coronary angiographic features, medication and outcome were compared in patients with and without SST. RESULTS: SST occurred in 17 patients, and the incidence was 3.7%. Univariate predictors of SST were being a current smoker (53.0%vs. 82.4%, p = 0.01), Killip class >or= II (38.4%vs. 58.8%, p = 0.05), no coronary re-flow after stenting (6.2%vs. 17.6%, p = 0.05) and lack of coprescription with a statin (39.5%vs. 5.9%, p<0.01). After multivariate analysis, being a current smoker (odds ratio = 4.76; 95% confidence interval 1.20-18.95) and using statin therapy (odds ratio = 0.09; 95% confidence interval = 0.01-0.75) were independent correlates of SST. Patients with SST were associated with higher 30-day mortality (37.5%vs. 3.1%, p<0.01) and all-cause mortality (23.5%vs. 5.3%, p = 0.01) at long-term follow-up. CONCLUSION: Although SST is rare in patients with STEMI treated by primary stenting, it imparts a significantly higher mortality at short-term and long-term follow-up. Being a current smoker and the lack of co-prescription with a statin were associated with higher incidence of SST. Our results suggest initiation of statin therapy in patients with STEMI should be considered before discharge.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Infarto del Miocardio/epidemiología , Stents , Trombosis/epidemiología , Adulto , Anciano , Angioplastia de Balón , Angioplastia Coronaria con Balón/métodos , Angiografía Coronaria , Femenino , Cardiopatías , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/fisiopatología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Trombosis/etiología , Trombosis/fisiopatología , Resultado del Tratamiento
19.
Gene ; 460(1-2): 39-47, 2010 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-20399258

RESUMEN

Evolutionary expansion of a gene family may occur at both the DNA and RNA levels. The rat testis-specific Rtdpoz-T2 and -T1 (rT2 and rT1) retrogenes are members of the TD/POZ gene family which also includes the well-characterized SPOP gene. In this study, rT2/rT1 transcriptional activation in cancer cells is demonstrated; the cancer rT2/rT1 transcripts are structurally similar to the embryonic transcripts reported previously in frequent exonization of transposed elements. On database interrogation, we have identified an uncharacterized rT2/rT1-like SPOP paralog, designated as SPOP-like (SPOPL), in the human and rodent genomes. Ka/Ks analysis indicates that the SPOPL genes are under functional constraints implicating biological functions. Phylogenetic analyses further suggest that segmental duplication and retrotransposition events had occurred giving rise to new gene members or retrogenes in the human-rodent ancestors during the evolution of the TD/POZ gene family. Based on this and previous works, a model is proposed to map the routes of evolutionary expansion of the TD/POZ gene family. More importantly, different gene expression patterns of members of the family are depicted: intron-harboring members are ubiquitously expressed whereas retrogenes are expressed in tissue-specific and developmentally regulated manner, and are fortuitously re-activated in cancer cells involving exonization of transposed elements.


Asunto(s)
Antígenos de Histocompatibilidad/genética , Ratones/genética , Proteínas Nucleares/genética , Ratas/genética , Proteínas Represoras/genética , Secuencia de Aminoácidos , Animales , Línea Celular , Línea Celular Tumoral , Elementos Transponibles de ADN , Evolución Molecular , Expresión Génica , Humanos , Datos de Secuencia Molecular , Alineación de Secuencia , Activación Transcripcional
20.
Clin Cardiol ; 33(3): 140-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20235218

RESUMEN

BACKGROUND: There have been few studies done regarding young patients with ST-elevation myocardial infarction (STEMI). The purpose of this study was to investigate the clinical characteristics and coronary angiographic features in young patients with STEMI. METHODS: We collected data on 849 consecutive patients with STEMI from 1992 to 2006. Baseline clinical characteristics, coronary anatomy, and outcome were compared in young (< or =45 yrs) and older patients (>45 yrs). RESULTS: Young patients presented 11.6% of all patients with STEMI. These patients were predominantly male (92.9% vs 80.3%, P < 0.001), more likely to smoke (75.8% vs 47.2%, P < 0.001), obese (48.2% vs 27.9%, P = 0.002), have higher triglyceride levels (176.9 +/- 153.8 mg/dL vs 140.7 +/- 112.7 mg/dL, P = 0.005), and lower high-density lipoprotein cholesterol (37.1 +/- 7.9 mg/dL vs 42.8 +/- 14.3 mg/dL, P = 0.005) than older patients. Also, younger patients had a shorter hospital stay (7.1 +/- 4.9 d vs 8.5 +/- 6.7 d, P = 0.04), less in-hospital morbidity (29.3% vs 39.7%, P = 0.02), and mortality (3.0% vs 12.3%, P = 0.002). Killip class III or IV could predict in-hospital morbidity and mortality in young patients. Both groups had similar rates of repeated percutaneous coronary intervention (PCI; 45.5% vs 41.5%, P = 0.23) and reinfarction (6.1% vs 3.2%, P = 0.32). Mortality rate during follow-up was significantly lower in younger patients (3.0% vs 19.6%, P < 0.001). CONCLUSION: Cigarette smoking, obesity, and dyslipidemia were the most important modifiable risk factors in young patients with STEMI. These patients had a better outcome than older patients without differences in repeated PCI and reinfarction between them. Only Killip class III or IV could predict in-hospital morbidity and mortality in young patients with STEMI.


Asunto(s)
Infarto del Miocardio/epidemiología , Resultado del Tratamiento , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón , Intervalos de Confianza , Angiografía Coronaria , Vasos Coronarios , Dislipidemias/complicaciones , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/mortalidad , Infarto del Miocardio/prevención & control , Obesidad/complicaciones , Oportunidad Relativa , Pronóstico , Factores de Riesgo , Fumar/efectos adversos , Estadística como Asunto , Taiwán/epidemiología , Factores de Tiempo
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