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1.
Biol Bull ; 238(1): 25-40, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32163729

RESUMEN

The paired claws in Gazami crabs, Portunus trituberculatus, are bilaterally asymmetrical, and asymmetry is remarkable on the distal two segments of the first pereiopod, that is, the dactylus and propodus. Shells are exclusively cracked by use of the right chela, representing handedness. In Gazami crabs, handedness is reversed after autotomy of the right chela. Our study focused on the ontogeny of handedness and the mechanism of handedness reversal. Morphologically, asymmetry was first detected in megalopa larvae where the right propodus was significantly larger than the left, as was the canine at the base of the right dactylus. Presumably, the rate of chelagenesis differed between the left and right chelae. With these morphological features, the right chela functioned as a crusher. The crusher exerted a closing force two to three times that of the cutter. With loss of the right crusher, the left chela was bigger than the regenerated right chela and was converted to the crusher. In contrast, the performance of the regenerated right chela deteriorated compared to that of the original right crusher, and exertion of full closing force was inhibited by the more active left chela. Furthermore, crabs with two crusher chelae did not clearly show handedness. A decrease in size and performance of the regenerated right chela can be explained by a default program hypothesis. In conclusion, a difference in the chelagenesis rate results in bilateral asymmetry of the two chelipeds, and then handedness is generated by neural regulation in the thoracic ganglion innervating these claws. Since handedness is reversed after autotomy, the thoracic ganglion would not be lateralized in Gazami crabs. A default program hypothesis is proposed to explain the ontogeny of bilateral chela asymmetry and handedness reversal.


Asunto(s)
Braquiuros , Animales , Perros , Lateralidad Funcional , Larva
3.
Muscle Nerve ; 61(4): E31-E32, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31985845
4.
Adv Exp Med Biol ; 1232: 291-297, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893423

RESUMEN

We present an IoT-based monitoring system for healthcare that allows for long-term measurements of blood pressure (BP), heart rate (HR), and body weight (BW), as well as near-infrared spectroscopy (NIRS) for measurement of prefrontal cortex (PFC) activity. To verify the applicability of the system, it was set up in a local fitness gym for a preliminary study. A total of 39 subjects, selected from members of the gym, participated in the study. We analyzed the BP, HR, and BW data, collected from the subjects over one half-year. In addition, to assess the degree of mental stress of the subjects, we analysed left-right asymmetry of the PFC activity using the laterality index at rest (LIR) of the NIRS parameter. Results show that the subjects were able to measure their physiological data by themselves when they visited the gym, after being instructed how to perform the measurements. Furthermore, the results also indicate that ordinary people can continuously monitor physiological functions such as brain function in a non-medical facility, such as a fitness gym.


Asunto(s)
Monitoreo Fisiológico , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Anciano , Femenino , Lateralidad Funcional , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/normas , Autoexamen/normas , Estrés Psicológico
5.
J Stroke Cerebrovasc Dis ; 29(2): 104529, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31806455

RESUMEN

BACKGROUND: Controversial evidence suggests that right insular stroke may be associated with worse outcomes compared to the left insular ischemic lesion. OBJECTIVES: We investigated whether lateralization of insular stroke is associated with early and late outcome in terms of in-hospital complications, stroke recurrence, cardiovascular events, and death. METHODS: Data were prospectively collected from the Athens Stroke Registry. Insular cortex involvement was identified based on brain CT scans or MRI images. Patients were followed up prospectively at 1, 3, 6 months after hospital discharge and yearly thereafter up to 5-years or until death. The assessed outcomes were in-hospital complications, functional outcome assessed by the modified Rankin Scale, stroke recurrence, cardiovascular events, and death. Cox-regression analysis was performed to estimate the cumulative probability of each outcome according to the lateralization of insular strokes. RESULTS: Among the 1212 patients, 650 had left insular stroke involvement and 562 had right. New onset of in-hospital atrial fibrillation was similar between right and left insular strokes (11.6% versus 12.9%, P = .484). During the 5-year follow-up sudden death occurred in 21 (3.7%) patients with right insular compared to 30 (4.6%) with left insular stroke (P = .476). There was no difference between left and right insular strokes regarding mortality (adjusted odds ratio [OR]: .92, 95% confidence interval [CI]: .80-1.06), stroke recurrence (4.3% versus 4.9%; adjusted OR: .81 95% CI: .58-1.13), cardiovascular events, and sudden death (adjusted OR: .99, 95% CI: .76-1.29) and on death and dependency (adjusted OR: .88, 95% CI: .75-1.02) during a 5-year follow up. CONCLUSIONS: Lateralization of insular ischemic stroke involvement is not associated with stroke outcomes.


Asunto(s)
Isquemia Encefálica/fisiopatología , Corteza Cerebral/irrigación sanguínea , Lateralidad Funcional , Accidente Cerebrovascular/fisiopatología , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/mortalidad , Isquemia Encefálica/terapia , Causas de Muerte , Circulación Cerebrovascular , Progresión de la Enfermedad , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Recurrencia , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/terapia , Factores de Tiempo
7.
Crit Rev Oncol Hematol ; 145: 102823, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31783291

RESUMEN

We conducted a systemic search of several databases for randomized controlled trials (RCTs) that reported efficacy and safety outcomes of drugs for left-sided and right-sided metastatic colorectal cancer (mCRC), to identify the best available treatment. A network meta-analysis with mixed comparisons was created to interpret the best treatment option using the surface under the cumulative ranking curve. In the left-sided rat sarcoma (RAS) wild-type (WT) mCRC patients, bevacizumab, panitumumab, or cetuximab with chemotherapy groups showed a significantly better objective response rate than the chemotherapy alone group. The progression-free survival (PFS) and overall survival were better with panitumumab or cetuximab with chemotherapy than with chemotherapy alone. In the right-sided RAS WT mCRC patients, PFS for bevacizumab with chemotherapy was significantly better than that for cetuximab with chemotherapy. Cetuximab, closely followed by panitumumab, is the most effective treatment in left-sided RAS WT mCRC. Bevacizumab is more effective in right-sided mCRC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Colorrectales , Proteínas Proto-Oncogénicas B-raf , Anticuerpos Monoclonales , Bevacizumab , Cetuximab , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Lateralidad Funcional , Humanos , Metaanálisis en Red
8.
J Stroke Cerebrovasc Dis ; 29(2): 104544, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31818684

RESUMEN

BACKGROUND: Bimanual coordination is essential for performing many everyday interlimb actions that require successful spatiotemporal interactions between the 2 arms. This systematic review and meta-analysis investigates bimanual coordination function of the upper extremities in patients with stroke. METHODS: Seventeen studies that compared bimanual coordination functions in patients with stroke and age-matched healthy controls qualified for this meta-analysis. We categorized 25 comparisons from the 17 qualified studies into 6 types of bimanual actions based on 3 task constraints: (1), symmetry versus asymmetry movements, (2) parallel versus cooperative movements, and (3) independent goals versus a common goal. RESULTS: Random effects meta-analysis revealed that patients with stroke had impaired kinematic (Hedges's g = -1.232 and P < .0001) and kinetic (Hedges's g = -.712 and P = .001) control of bimanual coordination as compared with the age-matched healthy controls. The moderator variable analysis on the 6 types of bimanual actions showed that bimanual coordination impairments after stroke appeared while performing both asymmetrical bimanual movements and symmetrical bimanual movements to achieve a common goal. Moreover, we observed a potential relationship between greater time since stroke onset and increased interlimb coordination impairments for chronic patients. CONCLUSIONS: These findings suggest that restoring interlimb coordination functions after stroke may be a crucial rehabilitation goal for facilitating progress toward stroke motor recovery.


Asunto(s)
Lateralidad Funcional , Actividad Motora , Parálisis/rehabilitación , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/terapia , Extremidad Superior/inervación , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Parálisis/diagnóstico , Parálisis/fisiopatología , Recuperación de la Función , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
9.
Sports Biomech ; 19(2): 271-279, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29671697

RESUMEN

Numerous studies have investigated anterior cruciate ligament (ACL) injury risk by examining gender differences in knee and hip biomechanics during a side-step cutting manoeuvre since it is known that ACL injury often occurs during such a task. Recent investigations have also examined lower extremity (LE) biomechanics during side-step cutting in individuals following ACL reconstruction (ACLR). Common research practice is to compare knee and hip biomechanics of the dominant limb between groups but this can add considerable complexity for clinicians and researchers. At this time, it is not known if there is a difference in LE biomechanics between the dominant and non-dominant limb during side-step cutting. Three-dimensional kinematics and kinetics were collected while 31 healthy participants performed five, side-step cutting manoeuvres with the dominant and non-dominant limbs. Knee and hip variables examined are those commonly investigated in ACL injury literature. There were no differences between limbs in all but one variable (knee internal rotation). These results demonstrate that healthy individuals exhibit little side-to-side differences in certain LE biomechanics when performing a side-step cutting manoeuvre. These findings can be utilised by clinicians when conducting dynamic evaluations of their ACLR patients and when developing injury prevention and rehabilitation programmes.


Asunto(s)
Lateralidad Funcional/fisiología , Extremidad Inferior/fisiología , Destreza Motora/fisiología , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior/fisiopatología , Fenómenos Biomecánicos , Femenino , Cadera/fisiología , Humanos , Cinética , Rodilla/fisiología , Masculino , Factores de Riesgo , Rotación , Estudios de Tiempo y Movimiento , Adulto Joven
10.
Brain Nerve ; 71(12): 1409-1417, 2019 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-31787629

RESUMEN

Lateralized behaviors are key movements of symmetrically organized animals. These behaviors are controlled by asymmetric activity of the bilateral brain. The neural mechanisms underlying these activities were recently revealed.


Asunto(s)
Encéfalo/fisiología , Lateralidad Funcional , Movimiento , Animales , Conducta Animal
12.
BMC Neurol ; 19(1): 279, 2019 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-31718589

RESUMEN

BACKGROUND: Cerebral infarction occurs when the arteries to brain are obstructed, and motor impairment contralateral to responsible lesion is commonly recognized. Few studies have profiled the characteristics of cases with ipsilateral motor impairment. We sought to characterize clinical features of patients with motor dysfunction caused by ipsilateral ischemic stroke. METHODS: We retrieved and analyzed the medical data for patients with ipsilateral cerebral infarction. Patients were regarded as having ipsilateral cerebral infarction if motor impairment is ipsilateral to recent stroke lesions. RESULTS: Only 22 patients with unusual ipsilateral cerebral infarction were included in this study. Ipsilateral limb paralysis was observed in all cases, and one case showed central facioplegia. Majority of patients with limb paralysis (90.9%, 20/22) presented with mild muscle strength deficits (MRC grading of 4 or more). Most of the patients (72.7%, 16/22) had a past history of stroke, and previous strokes were contralateral to the side of the recent stroke in 14 out of 16 patients (87.5%). No history of stroke or cerebral injury was identified in seven patients. With aspect of MRI findings, recent infarct lesions of all cases were located along the corticospinal tract. CONCLUSIONS: History of stroke plays an important role in the pathogenesis of ipsilateral motor impairment, and cortical reorganization in the unaffected hemisphere may contribute to the compensation of motor function after stroke. Besides that, some cases with first stroke may be due to impairment of ipsilateral uncrossed corticospinal fibers.


Asunto(s)
Infarto Cerebral/complicaciones , Infarto Cerebral/patología , Lateralidad Funcional/fisiología , Parálisis/etiología , Parálisis/fisiopatología , Adulto , Anciano , Infarto Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Trastornos Motores/etiología , Trastornos Motores/fisiopatología , Neuroimagen , Parálisis/diagnóstico por imagen , Accidente Cerebrovascular/complicaciones
13.
Rinsho Shinkeigaku ; 59(10): 646-651, 2019 Oct 26.
Artículo en Japonés | MEDLINE | ID: mdl-31564703

RESUMEN

We describe a 60-year-old woman with medically refractory left mesial temporal lobe epilepsy accompanied by Ross syndrome. The patient had a partial triad of Ross syndrome with hypohydrosis only on her right side (contralateral to the epileptic seizure focus), Adie's tonic pupil on the right, and areflexia while her seizures used to be medically refractory. However, her hypohidrosis and Adie's tonic pupil have completely changed in terms of laterality following nearly complete seizure freedom resutling from left temporal lobectomy. This unique change in laterality in Ross syndrome is most likely caused by remote effects of the near-absent epileptic acitivity, and it also may contribute to understanding the pathophysiological mechanism of Ross syndrome.


Asunto(s)
Epilepsia Refractaria/cirugía , Epilepsias Parciales/cirugía , Epilepsia del Lóbulo Temporal/cirugía , Lateralidad Funcional , Hipohidrosis/etiología , Hipohidrosis/fisiopatología , Procedimientos Neuroquirúrgicos/métodos , Lóbulo Temporal/cirugía , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Reflejo Anormal , Síndrome , Pupila Tónica/etiología , Pupila Tónica/fisiopatología
14.
J Stroke Cerebrovasc Dis ; 28(12): 104335, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31582271

RESUMEN

BACKGROUND: Occupation used in occupation-based intervention requires the use of 2 naturally coordinated hands. OBJECTIVE: To investigate by implementing occupation-based bilateral upper extremity training in medical setting to stroke patients and determine its effect in patients' bilateral upper extremity function recovery. METHODS: A total of 20 patients were randomly assigned to the experimental group (occupation-based bilateral upper extremity training) or control group (task-based bilateral upper extremity training). The intervention of the 2 groups was conducted 30 minutes a day, 5 times a week, and 4 weeks long. The outcome was assessed using the Canadian Occupational Performance Measure, Stroke Impact Scale, Action Research Arm Test, the Yonsei-Bilateral Activity Test, Accelerometer, and participants were assessed at baseline and after 4 weeks. RESULTS: There was a significant change in the satisfaction and performance status of occupational performance, strength, Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL), emotion, participant recovery in stroke recovery, gross movement in the function of the affected side, satisfaction in perform bilateral upper extremity in the experimental group compared to the control group. CONCLUSIONS: The clinical significance of this study is that this study demonstrated the effectiveness and usefulness of the training in the actual medical setting in improving upper extremity function and psychosocial factors.


Asunto(s)
Terapia por Ejercicio , Actividad Motora , Terapia Ocupacional , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Extremidad Superior/inervación , Actividades Cotidianas , Anciano , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Proyectos Piloto , Recuperación de la Función , República de Corea , Método Simple Ciego , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
15.
Handb Clin Neurol ; 163: 179-196, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31590729

RESUMEN

With the exception of language, hemispheric asymmetry has not historically been an important issue in the frontal lobe literature. Data generated over the past 20 years is forcing a reconsideration of this position. There is now considerable evidence to suggest that the left prefrontal cortex is an inference engine that automatically makes simple conceptual, logical, and causal connections to fill in missing information and eliminate uncertainty or indeterminacy. This is a fine-tuning of the "left hemisphere interpreter" account from the callosotomy patient literature. What is new is an understanding of the important contributions of the right prefrontal cortex to formal logical inference, conflict detection, and indeterminacy tolerance and maintenance. This chapter articulates these claims and reviews the data on which they are based. The chapter concludes by speculating that the inference capabilities of the left prefrontal cortex are built into the very fabric of language and can be accounted for by the left hemisphere dominance for language. The roles of the right PFC require multiple mechanisms for explanation. Its role in formal inference may be a function of its visual-spatial processing capabilities. Its role in conflict detection may be explained as a system for checking for consistency between existing beliefs and new information coming into the system and inferences drawn from beliefs and/or new information. There are at least three possible mechanisms to account for its role in indeterminacy tolerance. First, it could contain a representational system with properties very different from those of language, and an accompanying inference engine. Second, it could just contain this different representational system, and the information is at some point passed back to the left prefrontal cortex for inference. Third, the role of the right prefrontal cortex may be largely preventative. That is, it doesn't provide alternative representational and inference capabilities but simply prevents the left prefrontal cortex from settling on initial, local inferences. The current data do not allow differentiating between these possibilities. Successful real-world functioning requires the participation of both hemispheres.


Asunto(s)
Cognición/fisiología , Lateralidad Funcional/fisiología , Lenguaje , Corteza Prefrontal/fisiología , Toma de Decisiones/fisiología , Humanos , Pruebas Neuropsicológicas
16.
Handb Clin Neurol ; 163: 221-235, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31590732

RESUMEN

Recent research has demonstrated that the lateral prefrontal cortex is extensively involved in human memory, including working memory processes that support retention of information across short delays, and episodic long-term memory encoding and retrieval processes. This chapter reviews results from neuroimaging studies of memory, from noninvasive brain stimulation studies of memory, and from studies of memory in patients with prefrontal lesions. The available evidence is consistent with the idea that different prefrontal regions implement cognitive or executive control processes that support working memory and episodic long-term memory encoding and retrieval.


Asunto(s)
Lateralidad Funcional/fisiología , Memoria a Largo Plazo/fisiología , Corteza Prefrontal/fisiología , Mapeo Encefálico , Estimulación Eléctrica , Humanos , Neuroimagen , Pruebas Neuropsicológicas
17.
Dokl Biol Sci ; 487(1): 95-97, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31571073

RESUMEN

The visually driven instrumental conditioning of a single monkey (Macaca mulatta) was conducted after single-dose cranial irradiation with high-energy protons. The monkey executed saccades toward the visual stimuli and then responded by manually pressing right or left lever for stimuli in right or left half-field, respectively. The percentage of correct responses with dominant right hand exceeded the percentage of such responses with left hand and temporarily decreased two months after irradiation. A month later, the percentage of correct right-hand responses returned to the level before irradiation. No significant dynamic was found for changes in percentage of correct left-hand responses. The proton irradiation effect on right-hand responses suggests possible short-term disturbances in the eye-hand coordination for right handedness while the visual perception remains unaffected.


Asunto(s)
Irradiación Craneana/efectos adversos , Protones/efectos adversos , Desempeño Psicomotor , Animales , Condicionamiento Operante , Radiación Cósmica/efectos adversos , Lateralidad Funcional , Macaca mulatta , Masculino
19.
Medicine (Baltimore) ; 98(43): e17660, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31651891

RESUMEN

RATIONALE: The term crossed aphasia in dextrals (CAD) describes aphasia following a right hemisphere lesion in right-handed subjects. The diagnostic criteria for CAD, defined on the basis of clinical cases observed over the years, are aphasia; lesion in right hemisphere; strong preference for right hand use without familial history of left handedness; structural integrity of left hemisphere; and absence of brain damage in childhood. The studies of CAD have mainly been focused on the neurobiological mechanisms underlying the functional neurocognitive lateralization and organization of the brain, such as a dissociation between language and handedness, language and praxis, or other cognitive functions.Patient concerns: We described a case of a patient affected by an aphasic syndrome following cerebral hemorrhage located in right hemisphere. DIAGNOSIS: Considering the correlation between clinical data and instrumental investigations such as magnetic resonance imaging, we diagnose the patient with non-fluent aphasia. Specifically, the patient came to our attention showing a trans-cortical mixed aphasia that, later, developed in a trans-cortical motor aphasia. Contrary to most cases of CAD, our patient does not show apraxia and visuo-spatial neglect. Interventions language and visual attention when latter functions are related to right hemisphere. INTERVENTIONS: The rehabilitation program consisted in exercises stimulating verbal fluency, comprehension, reading, and writing. OUTCOMES: After 5 months of rehabilitation patient showed significant improvement in comprehension and absence of echolalia. LESSONS: At present there is no agreement about pathogenesis of CAD and neural mechanism is still unclear. Considering the clinical symptomatology, we can argue that we observed a non-fluent aphasia. However, a more large sample should be studied to asses the role of brain circuits.


Asunto(s)
Afasia/etiología , Afasia/rehabilitación , Hemorragia Cerebral/complicaciones , Adulto , Afasia/fisiopatología , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiopatología
20.
Elife ; 82019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31596230

RESUMEN

Motor cortex (M1) has lateralized outputs, yet neurons can be active during movements of either arm. What is the nature and role of activity across the two hemispheres? We recorded muscles and neurons bilaterally while monkeys cycled with each arm. Most neurons were active during movement of either arm. Responses were strongly arm-dependent, raising two possibilities. First, population-level signals might differ depending on the arm used. Second, the same population-level signals might be present, but distributed differently across neurons. The data supported this second hypothesis. Muscle activity was accurately predicted by activity in either the ipsilateral or contralateral hemisphere. More generally, we failed to find signals unique to the contralateral hemisphere. Yet if signals are shared across hemispheres, how do they avoid impacting the wrong arm? We found that activity related to each arm occupies a distinct subspace, enabling muscle-activity decoders to naturally ignore signals related to the other arm.


Asunto(s)
Brazo/inervación , Lateralidad Funcional , Corteza Motora/fisiología , Neuronas Motoras/fisiología , Movimiento , Animales , Macaca mulatta , Masculino
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