Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 285
Filtrar
1.
bioRxiv ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39464131

RESUMEN

Frailty indexes (FIs) capture health status in humans and model organisms. To accelerate our understanding of biological aging and carry out scalable interventional studies, high-throughput approaches are necessary. We previously introduced a machine vision-based visual frailty index (vFI) that uses mouse behavior in the open field to assess frailty using C57BL/6J (B6J) data. Aging trajectories are highly genetic and are frequently modeled in genetically diverse animals. In order to extend the vFI to genetically diverse mouse populations, we collect frailty and behavior data on a large cohort of aged Diversity Outbred (DO) mice. Combined with previous data, this represents one of the largest video-based aging behavior datasets to date. Using these data, we build accurate predictive models of frailty, chronological age, and even the proportion of life lived. The extension of automated and objective frailty assessment tools to genetically diverse mice will enable better modeling of aging mechanisms and enable high-throughput interventional aging studies.

2.
Kathmandu Univ Med J (KUMJ) ; 22(85): 45-48, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39324457

RESUMEN

Background Upper gastrointestinal (UGI) bleeding is a severe medical condition that requires prompt evaluation and management. Understanding the clinical and endoscopic findings in patients presenting with upper gastrointestinal bleeding is essential for accurate diagnosis and effective treatment. Objective To investigate the age and sex composition, clinical presentations, and endoscopic findings of patients with upper gastrointestinal bleeding at a tertiary care hospital. Method A total of 561 patients with upper gastrointestinal bleeding were included in the study. Data on age, sex, and clinical presentation were collected for each patient. Endoscopic findings were recorded, and the relative frequency of various upper gastrointestinal lesions was analyzed. Result The age distribution of patients revealed that 40.82% were between 15 and 45 years, 32.98% were aged 46 to 65 years, and 26.20% were above 65 years. Among the patients, 73.08% were male and 26.92% were female. Hematemesis was observed in 248 cases, while melena was present in 136 cases, and both were present in 171 cases. Recent onset anemia with positive occult blood was reported in 6 patients. The most common endoscopic finding was varices (39.39%), followed by ulcers (15.51%). Mallory Weiss tear was noted in 5.53% of cases. Conclusion According to our findings, varices are the most common endoscopic finding in individuals with upper gastrointestinal bleeding rather than peptic ulcer disease. The considerable increase in varices emphasizes the critical importance of early identification and care in high-risk individuals, as well as contributing to a better understanding of upper gastrointestinal bleeding.


Asunto(s)
Endoscopía Gastrointestinal , Hemorragia Gastrointestinal , Centros de Atención Terciaria , Humanos , Masculino , Femenino , Persona de Mediana Edad , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Adulto , Anciano , Endoscopía Gastrointestinal/métodos , Adolescente , Várices Esofágicas y Gástricas/diagnóstico , Várices Esofágicas y Gástricas/complicaciones , Nepal/epidemiología , Adulto Joven , Melena/etiología
3.
Cureus ; 16(8): e67827, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39323660

RESUMEN

Mycobacterium avium is a slow-growing nontuberculous mycobacterium (NTM) requiring prolonged treatment with multiple antimicrobials. It primarily affects immunocompromised patients and causes infection of the respiratory tract, skin, and soft tissue. While enteric carriage of M. avium has been reported, it has not been associated with clinical infection in immunocompetent hosts. To our knowledge, this is the first case report of a perirectal abscess caused by primary M. avium infection in an otherwise healthy patient and indicates the importance of considering NTMs as causative organisms in intraabdominal and enteric abscesses even among immunocompetent individuals when multiple courses of antibiotics are ineffective.

4.
Kathmandu Univ Med J (KUMJ) ; 22(86): 144-148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39328101

RESUMEN

Background Kidney disease includes diseases of the glomerulus, tubular disorders, and conditions associated with hematuria or proteinuria. Urinalysis can be a reliable and easy tool to screen. Objective In this study, we aim to study the prevalence of renal and urinary tract diseases among the pediatric population in a tertiary hospital in Nepal. Method A single-center retrospective cross-sectional study was conducted from 2022 to 2023 in the pediatric department. Information was obtained regarding clinicalepidemiological profile, associated condition, investigations, diagnosis, and duration of hospital stay, management, and outcome. Result The prevalence of renal disease was 5.6%, with urinary tract infection being the most common diagnosis. Maximum cases presented between one and five years with a male-to-female ratio of 1.1:1 and 80.9% of the patients had new onset disease. The mean duration of hospital stay was six days. The mortality rate in renal diseases was 3.2%. Conclusion Renal diseases make up a significant portion of pediatric admissions. Renal diseases contribute to significant morbidity and mortality. A large number of cases of renal diseases are due to infective etiology hence they are preventable and curable. Renal disease in children presents with vague symptoms and signs. Routine screening of renal diseases is needed for early diagnosis and reduction in morbidity and mortality.


Asunto(s)
Países en Desarrollo , Enfermedades Renales , Centros de Atención Terciaria , Enfermedades Urológicas , Humanos , Masculino , Femenino , Nepal/epidemiología , Centros de Atención Terciaria/estadística & datos numéricos , Prevalencia , Estudios Retrospectivos , Estudios Transversales , Preescolar , Niño , Lactante , Enfermedades Renales/epidemiología , Enfermedades Renales/diagnóstico , Enfermedades Urológicas/epidemiología , Enfermedades Urológicas/diagnóstico , Adolescente , Tiempo de Internación/estadística & datos numéricos , Infecciones Urinarias/epidemiología , Infecciones Urinarias/diagnóstico
6.
Chemphyschem ; 25(17): e202400360, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38780298

RESUMEN

Adsorption in nanoporous materials is one strategy that can be used to store hydrogen at conditions of temperature and pressure that are economically viable. Adsorption capacity of nanoporous materials depends on surface area which can be enhanced by incorporating a hierarchical pore structure. We report grand canonical Monte Carlo (GCMC) simulation results on the adsorption of hydrogen in hierarchical models of silicalite that incorporate 4 nm wide mesopores in addition to the 0.5 nm wide micropores at 298 K, using different force fields to model hydrogen. Our results suggest that incorporating mesopores in silicalite can enhance adsorption by at least 20 % if electrostatic interactions are not included and up to 100 % otherwise. Incorporating electrostatic interactions results in higher adsorption by close to 100 % at lower pressures for hierarchical silicalite whereas for unmodified silicalite, it is less significant at all pressures. Hydroxylating the mesopore surface in hierarchical silicalite results in an enhancement in adsorption at pressures below 1 atm and suppression by up to 20 % at higher pressures. Temperature dependence at selected pressures exhibits expected decrease in adsorption amounts at higher temperatures. These findings can be useful in the engineering, selection, and optimization of nanoporous materials for hydrogen storage.

7.
Conserv Biol ; 38(1): e14108, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37144480

RESUMEN

Identifying locations of refugia from the thermal stresses of climate change for coral reefs and better managing them is one of the key recommendations for climate change adaptation. We review and summarize approximately 30 years of applied research focused on identifying climate refugia to prioritize the conservation actions for coral reefs under rapid climate change. We found that currently proposed climate refugia and the locations predicted to avoid future coral losses are highly reliant on  excess heat metrics, such as degree heating weeks. However, many existing alternative environmental, ecological, and life-history variables could be used to identify other types of refugia that lead to the desired diversified portfolio for coral reef conservation. To improve conservation priorities for coral reefs, there is a need to evaluate and validate the predictions of climate refugia with long-term field data on coral abundance, diversity, and functioning. There is also the need to identify and safeguard locations displaying resistance toprolonged exposure to heat waves and the ability to recover quickly after thermal exposure. We recommend using more metrics to identify a portfolio of potential refugia sites for coral reefs that can avoid, resist, and recover from exposure to high ocean temperatures and the consequences of climate change, thereby shifting past efforts focused on avoidance to a diversified risk-spreading portfolio that can be used to improve strategic coral reef conservation in a rapidly warming climate.


Diversificación de los tipos de refugio necesarios para asegurar el futuro de los arrecifes de coral sujetos al cambio climático Resumen Una de las principales recomendaciones para la adaptación al cambio climático es identificar los refugios de los arrecifes de coral frente al estrés térmico del cambio climático y mejorar su gestión. Revisamos y resumimos ∼30 años de investigación aplicada centrada en la identificación de refugios climáticos para priorizar las acciones de conservación de los arrecifes de coral bajo un rápido cambio climático. Descubrimos que los refugios climáticos propuestos actualmente y las ubicaciones que pueden evitarlos dependen en gran medida de métricas de exceso de calor, como las semanas de calentamiento en grados (SCG). Sin embargo, existen muchas variables alternativas de historia vital, ambientales y ecológicas que podrían utilizarse para identificar otros tipos de refugios que resulten en el acervo diversificado que se desea para la conservación de los arrecifes de coral. Para mejorar las prioridades de conservación de los arrecifes de coral, es necesario evaluar y validar las predicciones sobre refugios climáticos con datos de campo a largo plazo sobre abundancia, diversidad y funcionamiento de los corales. También es necesario identificar y salvaguardar lugares que muestren resistencia a la exposición climática prolongada a olas de calor y la capacidad de recuperarse rápidamente tras la exposición térmica. Recomendamos utilizar más métricas para identificar un acervo de posibles lugares de refugio para los arrecifes de coral que puedan evitar, resistir y recuperarse de la exposición a las altas temperaturas oceánicas y las consecuencias del cambio climático, para así desplazar los esfuerzos pasados centrados en la evitación hacia un acervo diversificado de riesgos que pueda utilizarse para mejorar la conservación estratégica de los arrecifes de coral en un clima que se calienta rápidamente.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Ecosistema , Refugio de Fauna , Cambio Climático , Conservación de los Recursos Naturales
8.
Langmuir ; 39(49): 17653-17663, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38019151

RESUMEN

Electrostatic charge is a major part of modern-day aerosol filtration media (e.g., N95 respirators and surgical facemasks) that has remained poorly understood due to its complicated physics. As such, charging a fibrous material has relied on empiricism in dire need of a mathematical foundation to further advance product design and optimization. In this concern, we have conducted a series of numerical simulations to improve our understanding of how an electrostatically charged fiber captures airborne particles and to quantify how the fiber's dipole orientation impacts its capture efficiency. Special attention was paid to the role of Coulomb and dielectrophoretic forces in the capture of particles of different charge polarities (e.g., particles having a Boltzmann charge distribution). Simulation results were compared with the predictions of the popular empirical correlations from the literature and discussed in detail. Predictions of the empirical correlations better agreed with the simulation results obtained for fibers with a dipole perpendicular to the flow direction rather than for fibers with a dipole parallel to the flow. This indicates that such empirical correlations are more suitable for filters charged via contact electrification (friction charging), where the dipoles are mostly perpendicular to the flow direction, and less suitable for corona-charged media, where the fiber dipoles are generally parallel to the flow direction.

9.
Kathmandu Univ Med J (KUMJ) ; 21(81): 52-57, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37800426

RESUMEN

Background Children with congenital and traumatic upper limb amputation are undervalued in a low and middle-income country (LMIC) like Nepal. The use of a prosthetic hand can give them a feeling of self-reliance to perform their daily activities. However, prosthesis require periodic maintenance and replacement which could be a financial burden to some families. The e-Nable community has designed and developed three dimension printed prosthetic hands for children under 19 years old, and distributed them free of cost. Objective To explore the functionality of the three dimension printed prosthetic hands using semi-structured questionnaires and assess a series of daily tasks after three months prosthetic use. Method This descriptive cross-sectional study was conducted from July 2019 to June 2020, after receiving an ethical clearance from the Nepal Health Research Council (Registration number: 582/2019). Seventy six children (5-18 years old) who met the inclusion criteria were enrolled in this study. Data were collected using semistructured questionnaires, and observational methods to identify the benefits and drawbacks of the three dimensional prosthetic hands. Mean, standard deviation, and percentage were used to interpret the data. Result All participants could only lift light objects such as tray, tennis ball or a bottle of water. They had difficulty with those task that required complex movement and with lifting heavy objects. Moreover, only 47(61.8%) participants were completely satisfied with the prosthetic hand and the major reasons for dissatisfaction were tear of the rubber band or cord, and broken parts. Conclusion Participant were able to complete certain tasks using the e-Nable community three dimensional printed prosthetic hands.


Asunto(s)
Impresión Tridimensional , Extremidad Superior , Adolescente , Niño , Preescolar , Humanos , Estudios Transversales , Nepal , Diseño de Prótesis , Extremidad Superior/cirugía
10.
Cureus ; 15(8): e44002, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37746497

RESUMEN

Non-tuberculous mycobacteria (NTM) are slow-growing opportunistic pathogens that cause a variety of cutaneous, soft tissue, and pulmonary infections. On rare occasions, NTM causes chronic rhinosinusitis, with the majority of cases presenting in immunocompromised individuals. Other potential risk factors include the presence of foreign bodies, previous sinus surgery or chemoradiation, and use of contaminated water in sinus rinses. We report here a rare case of NTM rhinosinusitis in an otherwise immunocompetent 66-year-old female. The patient underwent functional endoscopic sinus surgery where intraoperative acid-fast bacteria cultures grew Mycobacterium abscessus. She received five weeks of broad-spectrum IV antibiotic therapy followed by three months of oral azithromycin, tigecycline, and linezolid. A one-year post-operative visit showed appropriate healing without crusting or visible infection. This case contributes to the small handful of documented presentations of NTM rhinosinusitis in immunocompetent patients. NTM should be considered when patients present with refractory rhinosinusitis as they may require extended courses of antibiotic treatment. Familiarity with risk factors can further expedite making a diagnosis, ensuring prompt initiation of treatment and relief of symptoms for patients.

11.
Cureus ; 15(7): e42121, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37602086

RESUMEN

A variety of gram-positive infections can be treated with daptomycin. Daptomycin-induced acute eosinophilic pneumonia (DEP) is a rare adverse drug reaction with nonspecific clinical findings of dyspnea, dry cough, and fever. Although diagnostic criteria exist, prompt recognition is important to prevent rapid progression and respiratory failure. In this case, a 69-year-old female was initially admitted due to a prosthetic joint infection; however, her case was complicated by DEP.

12.
J Neurol Neurosurg Psychiatry ; 94(11): 879-886, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37336643

RESUMEN

BACKGROUND: Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are variable and long-term durability is largely unproven. Anterior temporal lobectomy (ATL) remains an option for patients with MRgLITT treatment failure. However, the safety and efficacy of this staged strategy is unknown. METHODS: This multicentre, retrospective cohort study included 268 patients consecutively treated with mesial temporal MRgLITT at 11 centres between 2012 and 2018. Seizure outcomes and complications of MRgLITT and any subsequent surgery are reported. Predictive value of preoperative variables for seizure outcome was assessed. RESULTS: Engel I seizure freedom was achieved in 55.8% (149/267) at 1 year, 52.5% (126/240) at 2 years and 49.3% (132/268) at the last follow-up ≥1 year (median 47 months). Engel I or II outcomes were achieved in 74.2% (198/267) at 1 year, 75.0% (180/240) at 2 years and 66.0% (177/268) at the last follow-up. Preoperative focal to bilateral tonic-clonic seizures were independently associated with seizure recurrence. Among patients with seizure recurrence, 14/21 (66.7%) became seizure-free after subsequent ATL and 5/10 (50%) after repeat MRgLITT at last follow-up≥1 year. CONCLUSIONS: MRgLITT is a viable treatment with durable outcomes for patients with drug-resistant mTLE evaluated at a comprehensive epilepsy centre. Although seizure freedom rates were lower than reported with ATL, this series represents the early experience of each centre and a heterogeneous cohort. ATL remains a safe and effective treatment for well-selected patients who fail MRgLITT.


Asunto(s)
Epilepsia Refractaria , Epilepsia del Lóbulo Temporal , Epilepsia , Terapia por Láser , Humanos , Epilepsia del Lóbulo Temporal/cirugía , Estudios Retrospectivos , Convulsiones/cirugía , Epilepsia Refractaria/cirugía , Epilepsia/cirugía , Resultado del Tratamiento , Imagen por Resonancia Magnética , Rayos Láser
13.
Am J Infect Control ; 51(12): 1406-1410, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37172646

RESUMEN

BACKGROUND: The filtered far-UV-C (FFUV) handheld disinfection device is a small portable device that emits far UV-C at 222 nm. The objective of this study was to evaluate the device's ability to kill microbial pathogens on hospital surfaces and compare it to manual disinfection using germicidal sodium hypochlorite wipes. METHODS: A total of 344 observations (4 observations from 86 objects' surfaces) were sampled with 2 paired samples per surface: a pre- and a post-sodium hypochlorite and FFUV sample. The results were analyzed via a Bayesian multilevel negative binomial regression model. RESULTS: The estimated mean colony counts for the sodium hypochlorite control and treatment groups were 20.5 (95% uncertainty interval: 11.7-36.0) and 0.1 (0.0-0.2) colony forming units (CFUs), respectively. The FFUV control and treatment groups had mean colony counts of 22.2 (12.5-40.1) and 4.1 (2.3-7.2) CFUs. The sodium hypochlorite group and the FFUV group had an estimated 99.4% (99.0%-99.7%) and 81.4% (76.2%-85.7%) reduction in colony counts, respectively. CONCLUSIONS: The FFUV handheld device effectively reduced the microbial bioburden on surfaces in the health care setting. The major benefit of FFUV is likely seen when manual disinfection is not possible or when supplementing cleaners or disinfectants with the low-level disinfection properties.


Asunto(s)
Desinfectantes , Desinfección , Humanos , Desinfección/métodos , Hipoclorito de Sodio/farmacología , Teorema de Bayes , Desinfectantes/farmacología , Hospitales , Recuento de Colonia Microbiana , Rayos Ultravioleta
14.
Cureus ; 15(2): e35133, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36949980

RESUMEN

Oligella is a commensal bacteria genus of the human urinary tract that rarely precipitates clinical infections. We report the case of an asymptomatic 24-year-old male with a medical history of Tourette syndrome and the recent placement of deep brain stimulator leads, which were found to be co-infected with Oligella species during hardware implantation. This is the first reported case of a deep brain stimulator infection by Oligella, a potentially under-recognized and emerging opportunistic bacteria. We review the previously published cases of extra-genitourinary Oligella infections and detail the clinical management of this uncommon pathogen.

15.
Phys Chem Chem Phys ; 24(46): 28403-28410, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36398692

RESUMEN

Alternation in various properties of n-alkanes (CnH2n+2) as a function of carbon content (n) is termed 'odd-even effect'. Here, we report a comprehensive molecular dynamics simulation study on n-alkane systems carried out with n ranging between 3 (propane) and 8 (octane), examining the odd-even effect in melting point, density, intramolecular conformational ordering, translational and rotational motion. We observe an odd-even alternation in these properties, but with heptane (n = 7) exhibiting anomalous behavior for all except conformational ordering. Our simulations also show the presence of odd-even behavior in rotational and translational dynamics, below and above the melting point, respectively. The results highlight the role of both molecular shape and the variation in density and their interplay in the origins of the odd-even effect.


Asunto(s)
Alcanos , Simulación de Dinámica Molecular , Propano , Heptanos , Carbono
16.
Cureus ; 14(8): e27677, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36072211

RESUMEN

Disseminated gonococcal infections are rare clinical entities and a few progress to endocarditis. Endocarditis caused by Pseudomonasis even more infrequent, with the few reported cases associated with either intravenous drug use, prosthetic heart valves, or pacemakers. We report a case of a 25-year-old male patient with Tetralogy of Fallot presenting with anasarca and diagnosed with endocarditis due to Neisseria gonorrhoeae and Pseudomonas fluorescens. To our knowledge, this is the first case of tissue-proven infective endocarditis due to P. fluorescens with concomitant N. gonorrhoeae bacteremia. Clinical management of polymicrobial endocarditis in young adults includes obtaining a detailed sexual history, using multiple diagnostic methods to confirm endocarditis, and promptly initiating broad-spectrum antibiotic therapy.

17.
Cell Rep ; 38(2): 110231, 2022 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35021077

RESUMEN

Gait and posture are often perturbed in many neurological, neuromuscular, and neuropsychiatric conditions. Rodents provide a tractable model for elucidating disease mechanisms and interventions. Here, we develop a neural-network-based assay that adopts the commonly used open field apparatus for mouse gait and posture analysis. We quantitate both with high precision across 62 strains of mice. We characterize four mutants with known gait deficits and demonstrate that multiple autism spectrum disorder (ASD) models show gait and posture deficits, implying this is a general feature of ASD. Mouse gait and posture measures are highly heritable and fall into three distinct classes. We conduct a genome-wide association study to define the genetic architecture of stride-level mouse movement in the open field. We provide a method for gait and posture extraction from the open field and one of the largest laboratory mouse gait and posture data resources for the research community.


Asunto(s)
Marcha/genética , Marcha/fisiología , Equilibrio Postural/fisiología , Animales , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/fisiopatología , Aprendizaje Profundo , Conducta Exploratoria , Estudio de Asociación del Genoma Completo/métodos , Ratones , Movimiento/fisiología , Red Nerviosa/fisiología , Prueba de Campo Abierto/fisiología , Equilibrio Postural/genética
18.
Nat Aging ; 2(8): 756-766, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-37091193

RESUMEN

Heterogeneity in biological aging manifests itself in health status and mortality. Frailty indices (FIs) capture health status in humans and model organisms. To accelerate our understanding of biological aging and carry out scalable interventional studies, high-throughput approaches are necessary. Here we introduce a machine-learning-based visual FI for mice that operates on video data from an open-field assay. We use machine vision to extract morphometric, gait and other behavioral features that correlate with FI score and age. We use these features to train a regression model that accurately predicts the normalized FI score within 0.04 ± 0.002 (mean absolute error). Unnormalized, this error is 1.08 ± 0.05, which is comparable to one FI item being mis-scored by 1 point or two FI items mis-scored by 0.5 points. This visual FI provides increased reproducibility and scalability that will enable large-scale mechanistic and interventional studies of aging in mice.


Asunto(s)
Fragilidad , Humanos , Ratones , Animales , Anciano , Fragilidad/diagnóstico , Anciano Frágil , Reproducibilidad de los Resultados , Evaluación Geriátrica , Envejecimiento
19.
J Physiol ; 600(1): 75-94, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34761816

RESUMEN

Locomotion on complex terrains often requires vision. However, how vision serves locomotion is not well understood. Here, we asked when visual information necessary for accurate stepping is collected and how its acquisition relates to the step cycle. In cats of both sexes, we showed that a brief (200-400 ms) interruption of visual input can rapidly influence cat's walking along a horizontal ladder. Depending on the phase within the step cycle, a 200 ms period of darkness could be tolerated fully without any changes to the strides or could lead to minor increases of stride duration. The effects of 300-400 ms of visual input denial, which typically prolonged stances and/or swings, also depended on the phase of the darkness onset. The increase of the duration of strides was always shorter than the duration of darkness. We conclude that visual information for planning a swing is collected starting from the middle of the preceding stance until the beginning of the current swing. For a stance (and/or a swing of the other paw), visual information is collected starting from the end of the previous stance and until the middle of the current stance. Acquisition of visual information during these windows is not uniform but depends on the phase of the step cycle. Notably, both the extension of these windows and their non-homogeneity are closely related to the pattern of gaze behaviour in cats, described previously. This new knowledge will help to guide research and understanding of neuronal mechanisms of visuomotor integration and modulation of visual function by strides during locomotion. KEY POINTS: Cats, like humans, rely on vision to navigate in complex environments. In cats walking along a horizontally placed ladder, we show that visual information required for accurate stepping is collected in a non-uniform manner throughout the stride cycle. Brief denial of visual input during a swing prolongs the next stance of that forelimb. Denial of visual input during a stance prolongs this stance, as well as the next swing and stance. Denial during the first half of a stance has a greater effect than during the second half. The phase dependence of the use of vision for accurate stepping and the pattern of affected swings and stances are closely related to the previously described pattern of gaze behaviour in cats. This new knowledge opens new perspectives for research into neuronal mechanisms of visuomotor coordination and visual function during walking and for understanding related disorders.


Asunto(s)
Locomoción , Caminata , Animales , Gatos , Oscuridad , Electromiografía , Femenino , Miembro Anterior , Masculino
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA