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1.
Pharmacology ; 108(4): 409-415, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37257430

RESUMEN

Sertraline is one of the most prescribed antidepressants, but its pharmacokinetic (PK) properties are still not completely characterized. Using nonlinear mixed-effects modeling, we examined factors influencing sertraline PK variability in outpatients with major depressive disorder. Blood samples from 53 male and female adults treated with sertraline orally were collected at a steady state. Various demographic and clinical covariates were tested by stepwise regression procedure. We found that sertraline clearance is significantly influenced by serum concentrations of its main metabolite N-desmethylsertraline, whereas clearance of N-desmethylsertraline is affected by both creatinine clearance and drug daily dose. These results were confirmed by the reduction of points dispersion in goodness-of-fit plots for their predicted versus measured concentrations and with bootstrapping analyses. This finding can serve to inform sertraline dosing optimization, especially when changes in kidney function occur in treated individuals, to prevent adverse drug reactions and maximize therapeutic benefits.


Asunto(s)
Trastorno Depresivo Mayor , Sertralina , Adulto , Humanos , Masculino , Femenino , Sertralina/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/metabolismo , Depresión/tratamiento farmacológico , Antidepresivos/uso terapéutico
2.
Can J Physiol Pharmacol ; 97(5): 422-428, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30730758

RESUMEN

Acute kidney injury is a frequent disorder that can be mimicked by the application of different nephrotoxic agents, including carbon tetrachloride (CCl4), where kidney injury marker-1 (KIM-1) has been recognized as a highly specific marker. Melatonin is one of the most powerful natural antioxidants and has numerous beneficial properties. We evaluated the nephroprotective potential of 2 melatonin treatment regimens (pre- and post-intoxication) in a CCl4-induced acute kidney injury model based on the standard serum parameters, kidney tissue antioxidative capacity, KIM-1 levels, and kidney tissue morphological changes. The two treatment regimens were found to preserve kidney function, as judged from the evaluated standard serum parameters. Only when administered after the intoxication, melatonin preserved total kidney antioxidant capacity; pre-treatment melatonin only preserved reduced glutathione levels. An increase in tissue KIM-1 level was found to be prevented by both treatment regimens, which correlated with the morphological changes seen in the kidney tissues of animals treated with melatonin and CCl4. The findings of our study are in agreement with the known actions of melatonin in relieving kidney tissue oxidative burden, but also contribute to the understanding of its action by preventing an increase in KIM-1.


Asunto(s)
Tetracloruro de Carbono/efectos adversos , Citoprotección/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/lesiones , Melatonina/farmacología , Animales , Biomarcadores/sangre , Riñón/citología , Masculino , Ratas , Ratas Wistar
3.
Assist Technol ; 28(1): 22-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26479838

RESUMEN

This study compares the time required to activate a grasp or function of a hand prosthesis when using an electromyogram (EMG) based control scheme and when using a control scheme combining EMG and control signals from an inductive tongue control system (ITCS). Using a cross-over study design, 10 able-bodied subjects used a computer model of a hand and completed simulated grasping exercises. The time required to activate grasps was recorded and analyzed for both control schemes. End session mean activation times (ATs; seconds) for the EMG control scheme grasps 1 -5 were 0.80, 1.51, 1.95, 2.93, and 3.42; for the ITCS control scheme grasps 1 ‒5 they were 1.19, 1.89, 1.75, 2.26, and 1.80. Mean AT for grasps 1 and 2 was statistically significant in favor of the EMG control scheme (p = 0.030; p = 0.004). For grasp 3 no statistical significance occurred, and for grasps 4 and 5 there was a statistical significance in favour of the ITCS control scheme (p = 0.048; p = 0.004). Based on the amount of training and the achieved level of performance, it is concluded that the proposed ITCS control scheme can be used as a means of enhancing prosthesis control.


Asunto(s)
Miembros Artificiales , Electromiografía/métodos , Mano/fisiología , Dispositivos de Autoayuda , Lengua/fisiología , Adulto , Estudios Cruzados , Electromiografía/instrumentación , Femenino , Fuerza de la Mano , Humanos , Masculino , Diseño de Prótesis , Programas Informáticos
4.
Muscle Nerve ; 48(6): 930-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23512421

RESUMEN

INTRODUCTION: One important reason why functional electrical stimulation (FES) has not gained widespread clinical use is the limitation imposed by rapid muscle fatigue due to non-physiological activation of the stimulated muscles. We aimed to show that asynchronous low-pulse-rate (LPR) electrical stimulation applied by multipad surface electrodes greatly postpones the occurrence of muscle fatigue compared with conventional stimulation (high pulse rate, HPR). METHODS: We compared the produced force vs. time of the forearm muscles responsible for finger flexion in 2 stimulation protocols, LPR (fL = 10 Hz) and HPR (fH = 40 Hz). RESULTS: Surface-distributed low-frequency asynchronous stimulation (sDLFAS) doubles the time interval before the onset of fatigue (104 ± 80%) compared with conventional synchronous stimulation. CONCLUSIONS: Combining the performance of multipad electrodes (increased selectivity and facilitated positioning) with sDLFAS (decreased fatigue) can improve many FES applications in both the lower and upper extremities.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Fatiga/etiología , Fatiga/terapia , Hemiplejía/complicaciones , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Adulto , Anciano , Biofisica , Estimulación Eléctrica/métodos , Terapia por Estimulación Eléctrica/instrumentación , Electrodos , Femenino , Lateralidad Funcional , Hemiplejía/etiología , Humanos , Contracción Isométrica/fisiología , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones
5.
J Neuroeng Rehabil ; 9: 54, 2012 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-22876934

RESUMEN

BACKGROUND: The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. METHODS: The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype's software. RESULTS: The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. CONCLUSIONS: The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Tecnología Inalámbrica , Algoritmos , Amplificadores Electrónicos , Brazo/fisiología , Biorretroalimentación Psicológica , Sistemas de Computación , Computadores , Estimulación Eléctrica , Electrónica , Diseño de Equipo , Fuerza de la Mano/fisiología , Hemiplejía/rehabilitación , Humanos , Músculo Esquelético/fisiología , Procesamiento de Señales Asistido por Computador , Programas Informáticos
6.
J Neuroeng Rehabil ; 9: 66, 2012 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-23009589

RESUMEN

BACKGROUND: Functional electrical stimulation (FES) applied via transcutaneous electrodes is a common rehabilitation technique for assisting grasp in patients with central nervous system lesions. To improve the stimulation effectiveness of conventional FES, we introduce multi-pad electrodes and a new stimulation paradigm. METHODS: The new FES system comprises an electrode composed of small pads that can be activated individually. This electrode allows the targeting of motoneurons that activate synergistic muscles and produce a functional movement. The new stimulation paradigm allows asynchronous activation of motoneurons and provides controlled spatial distribution of the electrical charge that is delivered to the motoneurons. We developed an automated technique for the determination of the preferred electrode based on a cost function that considers the required movement of the fingers and the stabilization of the wrist joint. The data used within the cost function come from a sensorized garment that is easy to implement and does not require calibration. The design of the system also includes the possibility for fine-tuning and adaptation with a manually controllable interface. RESULTS: The device was tested on three stroke patients. The results show that the multi-pad electrodes provide the desired level of selectivity and can be used for generating a functional grasp. The results also show that the procedure, when performed on a specific user, results in the preferred electrode configuration characteristics for that patient. The findings from this study are of importance for the application of transcutaneous stimulation in the clinical and home environments.


Asunto(s)
Estimulación Eléctrica/instrumentación , Fuerza de la Mano/fisiología , Algoritmos , Suministros de Energía Eléctrica , Estimulación Eléctrica/métodos , Electrodos , Retroalimentación Fisiológica/fisiología , Femenino , Dedos/fisiología , Mano/inervación , Mano/fisiología , Hemiplejía/etiología , Hemiplejía/rehabilitación , Humanos , Masculino , Persona de Mediana Edad , Neuronas Motoras/fisiología , Movimiento , Músculo Esquelético/fisiología , Diseño de Prótesis , Recuperación de la Función , Programas Informáticos , Accidente Cerebrovascular/complicaciones , Rehabilitación de Accidente Cerebrovascular , Resultado del Tratamiento , Tecnología Inalámbrica , Articulación de la Muñeca/fisiología
7.
Comput Methods Biomech Biomed Engin ; 25(6): 593-602, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34459291

RESUMEN

Quantified assessment of spasticity is essential for the rehabilitation of persons with paralysis. We introduce the new SPAsticity Scale (SPAS), which we found highly correlated with the Modified Ashworth Score (MAS); yet, with a delicate gradation of spasticity compared to the MAS. The parameters defining the SPAS show the level and the type of spasticity (flexion or extension). The SPAS is based on a complex model of the pendulum type oscillations of the lower leg, which includes the spastic torques. The data to calculate SPAS were collected by a wearable instrument with two inertial measurement units and two EMG recording units in subjects with a complete chronic spinal cord injury.


Asunto(s)
Espasticidad Muscular , Traumatismos de la Médula Espinal , Humanos , Pierna , Espasticidad Muscular/diagnóstico , Rango del Movimiento Articular , Traumatismos de la Médula Espinal/diagnóstico
8.
Biomed Pharmacother ; 156: 113918, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36411611

RESUMEN

In this study, the hepatoprotective effect of aminoguanidine in acute liver damage caused by carbon tetrachloride-CCl4 at a dose of 1 mL/kg, i.p. was investigated in experimental rats. Ten days of preventive treatment with aminoguanidine before exposure to toxic CCl4, at a dose of 150 mg/kg, i.p., led to significant reduction in biochemical markers of acute liver injury-AST(p < 0.001), ALT (p < 0.01), SDH (p < 0.05) and reduction in pro-oxidative markers-H2O2 (p < 0.05), TOS (p < 0.01), TBARS, and LOOH (p < 0.001) in relation to rats treated only CCl4. Treatment with aminoguanidine resulted in a significant reduction in the consumption of antioxidant-GR (p < 0.01), GST, GPx, GSH (p < 0.001), and a decrease in pro-inflammatory-TNF-α (p < 0.01), IL-1ß, IL-6, NO and NGAL (p < 0.001) markers relative to animals exposed to CCl4 alone. Also, aminoguanidine pre-treatment leads to an increase in arginase activity (p < 0.001), and a decrease in citrulline concentration (p < 0.01), as well as polyamine catabolism enzyme activity-putrescin oxidase and spermine oxidase (p < 0.001) in comparison to the CCl4 group. Aminoguanidine led to a striking reduction of the necrotic field (p < 0.001), and a significant increase in the number of apoptotic hepatocytes (p < 0.001), as well as the proapoptotic markers-BAX and Caspase-3 (p < 0.05), compared to CCl4. The hepatoprotective mechanisms in CCl4 induce hepatotoxicity of aminoguanidine are based on the strong antioxidant effects, inhibition of pro-oxidative and pro-inflammatory mediators, as well as induction of damaged hepatocytes into apoptosis.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Ratas , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Peróxido de Hidrógeno , Tetracloruro de Carbono/toxicidad , Antioxidantes/metabolismo
9.
Artif Organs ; 35(1): 37-48, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20618232

RESUMEN

We present a practical system for controlling the prehension of a transradial prosthesis. The system is mounted on the artificial hand and comprises simple hardware and software that are convenient for real-time implementation. The hardware consists of a standard web camera and an ultrasound distance sensor. The control algorithm mimics biological mechanisms for the control of grasping and uses the measured distance to the target object and the method of computer vision to estimate the object's size and orientation. Based on these estimates, the algorithm outputs the following commands for the control of prehension: (i) the type of grasp and the aperture size appropriate for the target object; and (ii) the angle through which the wrist should be rotated (pronation/supination) in order to properly position the hand for the grasp. We have tested the system's performance with different targets (planar geometric shapes, real-life objects) under static conditions (i.e., when the system is stationary) and dynamic conditions (i.e., when the system moves toward the target). The size estimation was more accurate in the static experiments (error < 36%). Importantly, the system showed to be very robust with respect to the estimation errors, and the correct control commands were generated in most of the tested cases. The presented system is only one component of the hand controller, related strictly to the prehension phase of grasping. The final solution is envisioned as a combination of the presented system, inertial sensors (hand orientation), and a myoelectric control (triggering).


Asunto(s)
Miembros Artificiales , Mano/fisiología , Percepción Espacial , Algoritmos , Fenómenos Biomecánicos , Diseño de Equipo , Fuerza de la Mano , Humanos , Procesamiento de Imagen Asistido por Computador
10.
Tohoku J Exp Med ; 225(1): 71-6, 2011 09.
Artículo en Inglés | MEDLINE | ID: mdl-21878747

RESUMEN

Impaired motor and sensory function is common in the upper limb in humans after cerebrovascular stroke and it often remains as a permanent disability. Functional electrical stimulation therapy is known to enhance the motor function of the paretic hand; however, the mechanism of this enhancement is not known. We studied whether neural plasticity has a role in this therapy-induced enhancement of the hand motor function in 20 hemiparetic subjects with chronic stroke (age 53 ± 6 years; 7 females and 13 males; 10 with cerebral infarction and 10 with cerebral haemorrhage; and time since incident 2.4 ± 2.0 years). These subjects were randomized to functional electrical therapy or conventional physiotherapy group. Both groups received upper limb treatment (twice daily sessions) for two weeks. Behavioral hand motor function and neurophysiologic transcranial magnetic stimulation (TMS) tests were applied before and after the treatment and at 6-months follow-up. TMS is useful in assessing excitability changes in the primary motor cortex. Faster corticospinal conduction and newly found muscular responses were observed in the paretic upper limb in the functional electrical therapy group but not in the conventional therapy group after the intervention. Behaviourally, faster movement times were observed in the functional electrical therapy group but not in the conventionally treated group. Despite the small number of heterogeneous subjects, functional exercise augmented with individualized electrical therapy of the paretic upper limb may enhance neuroplasticity, observed as corticospinal facilitation, in chronic stroke subjects, along with moderate improvements in the voluntary motor control of the affected limb.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Mano/efectos de la radiación , Plasticidad Neuronal/fisiología , Paresia/terapia , Accidente Cerebrovascular/complicaciones , Análisis de Varianza , Femenino , Mano/patología , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología , Paresia/etiología , Estimulación Magnética Transcraneal
11.
Sensors (Basel) ; 11(11): 10571-85, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22346659

RESUMEN

A new method for estimation of angles of leg segments and joints, which uses accelerometer arrays attached to body segments, is described. An array consists of two accelerometers mounted on a rigid rod. The absolute angle of each body segment was determined by band pass filtering of the differences between signals from parallel axes from two accelerometers mounted on the same rod. Joint angles were evaluated by subtracting absolute angles of the neighboring segments. This method eliminates the need for double integration as well as the drift typical for double integration. The efficiency of the algorithm is illustrated by experimental results involving healthy subjects who walked on a treadmill at various speeds, ranging between 0.15 m/s and 2.0 m/s. The validation was performed by comparing the estimated joint angles with the joint angles measured with flexible goniometers. The discrepancies were assessed by the differences between the two sets of data (obtained to be below 6 degrees) and by the Pearson correlation coefficient (greater than 0.97 for the knee angle and greater than 0.85 for the ankle angle).


Asunto(s)
Aceleración , Marcha/fisiología , Articulaciones/fisiología , Tecnología de Sensores Remotos/métodos , Adulto , Algoritmos , Articulación del Tobillo/fisiología , Artrometría Articular/métodos , Fenómenos Biomecánicos , Prueba de Esfuerzo , Humanos , Articulación de la Rodilla/fisiología , Tecnología de Sensores Remotos/instrumentación , Caminata/fisiología , Tecnología Inalámbrica/instrumentación
12.
Biomed Tech (Berl) ; 66(5): 449-457, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34243223

RESUMEN

The gait assessment is instrumental for evaluating the efficiency of rehabilitation of persons with a motor impairment of the lower extremities. The protocol for quantifying the gait performance needs to be simple and easy to implement; therefore, a wearable system and user-friendly computer program are preferable. We used the Gait Master (instrumented insoles) with the industrial quality ground reaction forces (GRF) sensors and 6D inertial measurement units (IMU). WiFi transmitted 10 signals from the GRF sensors and 12 signals from the accelerometers and gyroscopes to the host computer. The clinician was following in real-time the acquired data to be assured that the WiFi operated correctly. We developed a method that uses principal component analysis (PCA) to provide a clinician with easy to interpret cyclograms showing the difference between the recorded and healthy-like gait performance. The cyclograms formed by the first two principal components in the PCA space show the step-to-step reproducibility. We suggest that a cyclogram and its orientation to the coordinate system PC1 vs. PC2 allow a simple assessment of the gait. We show results for six healthy persons and five patients with hemiplegia.


Asunto(s)
Marcha , Extremidad Inferior , Fenómenos Biomecánicos , Humanos , Análisis de Componente Principal , Reproducibilidad de los Resultados
13.
IEEE Trans Biomed Eng ; 68(6): 2011-2020, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33449876

RESUMEN

OBJECTIVE: This study aims at investigating the functional performance of a novel prosthesis control scheme integrating an inductive tongue interface and myoelectric control. The tongue interface allowed direct selection of the desired grasp while myoelectric signals were used to open and close the robotic hand. METHODS: The novel method was compared to a conventional sequential on/off myoelectric control scheme using functional tasks defined by Assistive Hand Assessment protocol. Ten able-bodied participants were fitted with the SmartHand on their left forearm. They used both the conventional myoelectric control and the Tongue and Myoelectric Hybrid interface (TMH) to accomplish two activities of daily living (i.e., preparing a sandwich and gift wrapping). Sessions were video recorded and the outcome measure was the completion time for the subtasks as well as the full tasks. RESULTS: The sandwich task was completed significantly faster, with 19% decrease in the completion time, using the TMH when compared to the conventional sequential on/off myoelectric control scheme (p < 0.05). CONCLUSION: The results indicate that the TMH control scheme facilitates the active use of the prosthetic device by simplifying grasp selection, leading thereby to faster completion of challenging and relevant tasks involving bimanual activities.


Asunto(s)
Miembros Artificiales , Procedimientos Quirúrgicos Robotizados , Actividades Cotidianas , Electromiografía , Mano , Fuerza de la Mano , Humanos , Diseño de Prótesis , Lengua
14.
Muscle Nerve ; 42(4): 556-62, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20665516

RESUMEN

We present a low-frequency stimulation method via multi-pad electrodes for delaying muscle fatigue. We compared two protocols for muscle activation of the quadriceps in paraplegics. One protocol involved a large cathode at 30 HZ (HPR, high pulse-rate), and the other involved four smaller cathodes at 16 HZ (LPR, low pulse-rate). The treatment included 30-min daily sessions for 20 days. One leg was treated with the HPR protocol and the other with the LPR protocol. Knee-joint torque was measured before and after therapy to assess the time interval before the knee-joint torque decreased to 70% of the initial value. The HPR therapy provided greater increases in muscle endurance and force in prolonged training. Yet the LPR stimulation produced less muscle fatigue compared to the HPR stimulation. The results suggest that HPR is the favored protocol for training, and LPR is better suited for prolonged stimulation.


Asunto(s)
Estimulación Eléctrica/métodos , Fatiga Muscular , Paraplejía/fisiopatología , Paraplejía/terapia , Músculo Cuádriceps/fisiopatología , Cuadriplejía/fisiopatología , Cuadriplejía/terapia , Adulto , Estimulación Eléctrica/instrumentación , Electrodos , Diseño de Equipo , Femenino , Humanos , Articulación de la Rodilla/fisiopatología , Masculino , Persona de Mediana Edad , Resistencia Física , Torque , Adulto Joven
15.
J Neuroeng Rehabil ; 7: 42, 2010 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-20731834

RESUMEN

BACKGROUND: Dexterous prosthetic hands that were developed recently, such as SmartHand and i-LIMB, are highly sophisticated; they have individually controllable fingers and the thumb that is able to abduct/adduct. This flexibility allows implementation of many different grasping strategies, but also requires new control algorithms that can exploit the many degrees of freedom available. The current study presents and tests the operation of a new control method for dexterous prosthetic hands. METHODS: The central component of the proposed method is an autonomous controller comprising a vision system with rule-based reasoning mounted on a dexterous hand (CyberHand). The controller, termed cognitive vision system (CVS), mimics biological control and generates commands for prehension. The CVS was integrated into a hierarchical control structure: 1) the user triggers the system and controls the orientation of the hand; 2) a high-level controller automatically selects the grasp type and size; and 3) an embedded hand controller implements the selected grasp using closed-loop position/force control. The operation of the control system was tested in 13 healthy subjects who used Cyberhand, attached to the forearm, to grasp and transport 18 objects placed at two different distances. RESULTS: The system correctly estimated grasp type and size (nine commands in total) in about 84% of the trials. In an additional 6% of the trials, the grasp type and/or size were different from the optimal ones, but they were still good enough for the grasp to be successful. If the control task was simplified by decreasing the number of possible commands, the classification accuracy increased (e.g., 93% for guessing the grasp type only). CONCLUSIONS: The original outcome of this research is a novel controller empowered by vision and reasoning and capable of high-level analysis (i.e., determining object properties) and autonomous decision making (i.e., selecting the grasp type and size). The automatic control eases the burden from the user and, as a result, the user can concentrate on what he/she does, not on how he/she should do it. The tests showed that the performance of the controller was satisfactory and that the users were able to operate the system with minimal prior training.


Asunto(s)
Miembros Artificiales , Cognición/fisiología , Mano/fisiología , Visión Ocular/fisiología , Actividades Cotidianas , Algoritmos , Amputación Quirúrgica , Fenómenos Biomecánicos , Árboles de Decisión , Electromiografía , Electrónica , Dedos , Fuerza de la Mano , Humanos , Movimiento , Diseño de Prótesis
16.
Diagnostics (Basel) ; 10(9)2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32899343

RESUMEN

Prostate cancer (PC) is one of the most frequent malignancies. Better biomarkers are constantly wanted, such as those which can help with the prediction of cancer behavior. What is also needed is a marker which may serve as a possible therapeutic target. Oxidative stress (OS), which is a hallmark of cancer, is included in the pathogenesis and progression of PC. We have conducted the present study to determine whether xanthine oxidase/dehydrogenase activity is the source of OS in prostate tissue. We have also determined the concentration of TBA-reactive substances (TBARS) and advanced oxidation protein products (AOPP), as well as the activity of catalase. Xanthine oxidase (XO) activity is significantly higher (p < 0.001) in tumor tissue when compared to the control healthy tissue. The concentration of TBARS (p < 0.001) and AOPP (p < 0.05) are also higher in tumor tissue. Catalase has raised its activity (p < 0.05) versus the control. There is also a strong correlation between XO activity and prostate-specific antigen (PSA) levels in the serum. These results indicate a significant role of XO activity in OS in prostate carcinogenesis, and it could be a possible theranostic biomarker, which can be important for a better understanding of the disease, its evolution, and prognosis. A promising treatment may be using XO inhibitors such as allopurinol as adjuvant therapy.

17.
Acta Dermatovenerol Croat ; 28(7): 240-241, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33834999

RESUMEN

Dear editor, Condylomata accuminatum (CA) is a human papillomavirus (HPV) related sexually transmitted infection (STI), clinically characterized by solitary or even clustered dark red or pink lesions solely affecting the anogenital area (1). CA involving the extragenital, non-mucosal skin has been sporadically reported (2-4). Diagnosis of CA is usually straightforward when the lesions are located on the anogenital area. However, involvement of extragenital skin may pose a diagnostic challenge. Herein, we report a rare case of giant linear extragenital CA without coexisting genital lesions, diagnosed with a synergic intervention of dermatoscopy and clinics. A 70-year-old Caucasian man was referred to our department for an atypical asymptomatic seborrheic keratosis presenting as a linear verrucous plaque (20 × 2 cm) with few solitary reddish satellite papules on the abdomen (Figure 1, a). No similar lesions were present in both cutaneous and mucosal districts. Medical history was unremarkable, and the patient denied having recent sexual intercourse or any history of condylomas. Remarkably, the patient underwent a diet in the last 8 months that resulted in a loss of 30 kg. We employed dermatoscopy to further assess the lesions, highlighting a finger-like pattern on the main lesion (Figure 1, c), while satellite lesions presented a mosaic pattern (Figure 1, b). The clinical appearance and these dermatoscopic findings were suggestive of condyloma acuminatum (CA), but due to its extraordinary presentation we also performed an incisional biopsy. Histopathological examination reviled features compatible with the diagnosis of CA (Figure 1, d, e). To better characterized the HPV genotype (high-risk and low-risk HPV) a polymerase chain reaction (PCR) from lesional tissue sample was performed and found HPV type 6 positivity. The lesions were successfully removed by electrosurgery. Regular follow-up was scheduled. Sexually transmitted infections (STIs) were also screened, namely syphilis, gonorrhea, chlamydia trachomatis, and HIV status. In addition, laboratory tests and imaging examinations (radiography of the chest and ultrasound examination of the abdomen) revealed no pathological findings. CA involving the extragenital skin has been reported within intertriginous areas, including the inframammary fold, the groin, and the axillary vault, as well as mucosal surface such as intraoral and conjunctival mucosa (1-5). In most cases, extragenital CA coexisted with genital lesions. Staples et al. reported three obese patients with extragenital CA on the skin of the abdominal pannus (3). However, all of the patients had involvement of the inguinal folds, from where the CA had extended. Generally, CA is acquired by genital, oral, or anal sexual contact. Among the wide spectrum of HPV genotypes, types 6 and 11 are responsible of 90% of CA (1). Our paradigmatic case allows us reflect on the concept of transitory immune dysregulation due to a significant amount of weight loss, and the position of the lesions in particular seems to suggest that frictional triggers may disrupt the barrier integrity, leading to higher probability of infection. Dermoscopy is a noninvasive diagnostic tool with a significant role in the assessment of melanocytic and non-melanocytic skin tumors. Furthermore, the utility of dermatoscopy has expanded to the field of inflammatory and infectious skin disease, where dermoscopy enhances the differential diagnosis between them. Seborrheic keratosis, as the most common benign epithelial tumor, can occur anywhere in the skin excluding the palms, soles, and mucosa (6). In the anogenital area, seborrheic keratosis usually resembles CA. However, dermatoscopically, seborrheic keratosis can be immediately identified by the presence of milia-like cysts, comedo-like openings, fissures, finger-print structures, and sharply demarcated borders (6). In contrast, reports of CA dermoscopy suggested four different dermoscopic patterns: fingerlike, mosaic, knoblike, and the most commonly, an unspecific pattern (7). Our case showed that dermoscopy of extragenital CA presented a mosaic pattern in an early stage of CA, while fully developed lesions revealed a fingerlike pattern, as has previously been reported by Dong et al. (7), where two different stages of clinical development of CA exhibit distinctive dermoscopic patterns, which correlates with our case. We did not observe the typical dermoscopic features of seborrheic keratosis. CA arising in an extragenital area is very rare and perhaps also underestimated. Thus, dermatologists should be aware of this unusual presentation even in the absence of genital HPV involvement. Moreover, dermoscopy may facilitate CA recognition in a such uncommon location. To our knowledge, this is the first report of extragenital condyloma acuminatum documented dermoscopically.


Asunto(s)
Condiloma Acuminado , Queratosis Seborreica , Neoplasias Cutáneas , Anciano , Condiloma Acuminado/diagnóstico , Dermoscopía , Diagnóstico Diferencial , Humanos , Masculino , Piel , Neoplasias Cutáneas/diagnóstico
18.
J Neurosci Methods ; 178(1): 174-81, 2009 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-19109996

RESUMEN

We present a method for automatic determination of the shape and position of the surface electrode for selective control of fingers extension and flexion by means of electrical stimulation. The multi-pad electrodes used in the experiments comprised 24 pads (1cm diameter) distributed over an area (7 cm x 10 cm) positioned over dorsal and volar aspects of the forearm. The four-channel stimulation system for grasping comprised also an oval reference electrode over the carpal tunnel, and two oval electrodes over the thenar and thumb extensor muscles. We measured seven angles: proximal inter-phalangeal and metacarpal phalangeal index and ring finger joint rotations, wrist extension/flexion and ulnar/radial rotation, and pronation/supination of the forearm. The optimal electrode was determined as the combination of pads that led to fingers, wrist and forearm rotations being similar to the trajectories of healthy individuals when grasping. The similarity of trajectories was assessed by analyzing the aggregate error defined as the sum of squares of differences between the angles measured when stimulating the forearm in tetraplegics and the angles measured in healthy individuals. The aggregate errors were determined from measurements during sequential stimulation of each of the 24 pads. The analysis comprised hand opening and closing for palmar and lateral grasps. The time for determining the optimal electrode was about 10 min. The optimal electrodes had different branched shapes in each of the six tetraplegics; however, once determined they remained unchanged when tested on different days.


Asunto(s)
Estimulación Eléctrica/instrumentación , Electrodos , Dedos/fisiología , Reflejo/fisiología , Adulto , Fuerza de la Mano/fisiología , Humanos , Articulaciones/fisiología , Cuadriplejía/fisiopatología , Procesamiento de Señales Asistido por Computador , Muñeca/inervación , Adulto Joven
19.
Artif Organs ; 33(1): 54-60, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19178441

RESUMEN

We developed the STIMBELT, an electrical stimulation system that comprises a lumbar belt with up to eight pairs of embedded electrodes and an eight-channel electronic stimulator. The STIMBELT is an assistive system for the treatment of low-back pain (LBP). We describe here technical details of the system and summarize the results of its application in individuals with subacute and chronic LBP. The direct goals of the treatment were to relieve pain, reduce muscle spasms, increase strength and range of motion, and educate individuals with LBP in reducing the chances of its reoccurrence. The outcome measures include: a Visual Analogue Scale (VAS), the Oswestry LBP Disability Questionnaire, the Short Form (SF)-12 health survey, and the Manual Muscle Test. The results indicate significant benefits for individuals who use the STIMBELT in addition to the conventional therapy as opposed to only the conventional therapy.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Dolor de la Región Lumbar/terapia , Humanos , Dimensión del Dolor , Programas Informáticos , Resultado del Tratamiento , Interfaz Usuario-Computador
20.
NeuroRehabilitation ; 25(1): 45-58, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19713618

RESUMEN

This review presents technologies used in and assesses the main clinical outcomes of electrical therapies designed to speed up and increase functional recovery in stroke patients. The review describes methods which interface peripheral systems (e.g., cyclic neural stimulation, stimulation triggered by electrical activity of muscles, therapeutic functional electrical stimulation) and transcranial brain stimulation with surface and implantable electrodes. Our conclusion from reviewing these data is that integration of electrical therapy into exercise-active movement mediated by electrical activation of peripheral and central sensory-motor mechanisms enhances motor re-learning following damage to the central nervous system. Motor re-learning is considered here as a set of processes associated with practice or experience that leads to long-term changes in the capability for movement. An important suggestion is that therapeutic effects are likely to be much more effective when treatment is applied in the acute, rather than in the chronic, phase of stroke.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Rehabilitación de Accidente Cerebrovascular , Humanos , Plasticidad Neuronal/fisiología , Desempeño Psicomotor/fisiología , Recuperación de la Función , Accidente Cerebrovascular/fisiopatología
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