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1.
Behav Brain Res ; 463: 114892, 2024 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-38309374

RESUMEN

Taurine is a non-essential ß sulfonated amino acid involved in a plethora of biological functions in the mammalian central nervous system. Taurine is easily accessible in energy drinks for human consumption. Previous preclinical and clinical reports suggest that acute systemic administration of taurine could inhibit some of the behavioral and metabolic effects of alcohol use disorder. Overall, both in rodent and human studies, acute taurine administration reduced voluntary alcohol intake. This study aimed to assess the pharmacological effects of taurine (intracerebroventricular; i.c.v.) on ethanol intake/preference of rats either control (i.e., alcohol naïve) or forced ethanol intake (since juvenile age with a chronic intermittent access model). In addition, to explore anxiety-like behavior (through defensive burying behavior test) as pharmacological control of taurine. We found that acute (i.c.v.) taurine reduced alcohol consumption, i.e., taurine significantly decreased both alcohol intake and preference in adult male Wistar rats. Moreover, taurine elicits an anxiolytic-like effect in all administered groups independently of previous alcohol exposure.


Asunto(s)
Alcoholismo , Taurina , Humanos , Ratas , Animales , Masculino , Taurina/farmacología , Ratas Wistar , Etanol/farmacología , Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Mamíferos
2.
Parasitol Res ; 123(1): 97, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38224359

RESUMEN

Cases of sarcoptic mange in the wildlife population have been increasing around the world in recent years. In this study, we report the first case of severe sarcoptic mange in two Andean foxes (Lycalopex culpaeus) and molecularly analyze the collected mites. The National Forestry and Wildlife Service of Lima, Peru, found an adult male Andean fox in the province of Callao in August 2022. The veterinarians decided to euthanize the fox due to the severity of the mange. In August 2023, an adult male Andean fox was found dead in the province of Huaral by veterinarians. Both foxes were sent to the veterinary school in Lima for necropsy. Skin samples from different body zones were digested in buffer lysis, and mites were detected in the tissue samples. A morphological diagnosis identified the mites as Sarcoptes scabiei. The mites from both foxes had the same nuclear (ITS2) and mitochondrial (cox1) genetic marker sequences as the S. scabiei sequences from dogs, vicunas, Andean foxes, and water buffalos recorded in GenBank. Unlike ITS2, phylogenetic analysis of S. scabiei cox1 showed host-related nucleotide sequence polymorphisms. Future molecular studies of S. scabiei from different hosts and localities will be necessary to better understand the transmission of this disease in Andean foxes.


Asunto(s)
Zorros , Escabiosis , Animales , Masculino , Animales Salvajes , Perú , Filogenia , Sarcoptes scabiei/genética , Escabiosis/veterinaria
3.
Acta Trop ; 249: 107074, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956821

RESUMEN

Hemotrophic mycoplasmas (hemoplasmas) are epierythrocytic bacteria that infect wild and domestic animals, and can cause anemia in some of them. They are considered emerging and zoonotic pathogens, causing serious health problems in wildlife. Candidatus Mycoplasma haemolamae is the only species of hemoplasma that infects domestic South American camelids (alpacas and llamas), with limited studies in wild camelids. Therefore, the objective of this study was to determine the prevalence of Candidatus M. haemolamae in vicunas (Vicugna vicugna) from the Pampa Galeras National Reserve, located in the Ayacucho region of Peru, using molecular diagnosis. For this, blood samples from 79 vicunas were collected, which were molecularly analyzed by partially amplifying the 16S ribosomal RNA gene of Mycoplasma sp. Fourteen vicunas (17.7 %) were positive for the molecular diagnosis of Mycoplasma sp. All PCR-positive products were sequenced and showed more than 99 % identity with Candidatus M. haemolamae. Statistical analysis showed that tick-infested vicunas had 6.10 odds of presenting Candidatus M. haemolamae compared with tick-free vicunas. Sex and age were not associated with Candidatus M. haemolamae infections. This is the first report of hemoplasmas in vicunas, a wild South American camelid, demonstrating that the pathogen can have both a domestic and a wild life cycle. Future studies are necessary to know the current situation of this pathogen in domestic and wild camelids from other locations in Peru.


Asunto(s)
Camélidos del Nuevo Mundo , Mycoplasma , Animales , Camélidos del Nuevo Mundo/microbiología , Perú/epidemiología , Animales Domésticos , Mycoplasma/genética , Animales Salvajes , ARN Ribosómico 16S/genética
4.
Int J Psychol Res (Medellin) ; 16(2): 105-121, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38106958

RESUMEN

Stress is fundamental for health and adaptation; it is an evolutionarily conserved response that involves several systems in the organism. The study of the stress response could be traced back to the end of the nineteenth century with George Beard's or Claude Bernard's work and, from that moment on, several studies that have allowed the elucidation of its neurobiology and the consequences of suffering from it were consolidated. In this theoretical review, we discuss the most relevant researches to our knowledge on the study of stress response, from the concept of stress, its neurobiology, the hormonal response during stress, as well as its regulation, the effects of acute and chronic stress, stress from cognition, the different stress responses during life, as well as its relationship with different psychiatric disorders. Taken together, the reviewed research updates the classic perspective on stress, increasing the factors that should be considered in research to explore the effects of stress on health.


El estrés es fundamental para la salud y la adaptación; es una respuesta conservada evolutivamente que implica a varios sistemas del organismo. El estudio de la respuesta de estrés se remonta a finales del siglo xix con los trabajos de George Beard o Claude Bernard y a partir de ese momento se consolidaron diversos estudios que han permitido dilucidar su neurobiología y las consecuencias de padecerlo. En esta revisión teórica, abordamos lo más relevante para nuestro conocimiento sobre el estudio de la respuesta de estrés, desde el concepto de estrés, su neurobiología, la respuesta hormonal durante el estrés, así como su regulación, los efectos del estrés agudo y crónico, el estrés desde la cognición, las diferentes respuestas de estrés a lo largo de la vida, además de su relación con diferentes trastornos psiquiátricos. En conjunto, las investigaciones revisadas actualizan la perspectiva clásica sobre el estrés, incrementando los factores que deben tenerse en cuenta en la investigación para explorar los efectos del estrés sobre la salud.

5.
Pharmacol Rep ; 75(5): 1299-1308, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37658980

RESUMEN

BACKGROUND: Periaqueductal gray matter (PAG) is a brain region rich in kappa-opioid receptors (KOR). KOR in PAG mediates behavioral responses related to pain integration, and panic response, among others. Its participation in the addiction phenomena has been poorly studied. Hence, this preliminary study explored the pharmacological effects of KOR stimulation/blockade in dorsal-PAG (D-PAG) during alcohol withdrawal on anxiety-type behaviors and alcohol intake/preference. METHODS: Juvenile male Wistar rats were unexposed (A-naïve group) or exposed to alcohol for 5 weeks and then restricted (A-withdrawal group). Posteriorly, animals received intra D-PAG injections of vehicle (10% DMSO), salvinorin A (SAL-A; a selective KOR agonist), or 2-Methyl-N-((2'-(pyrrolidin-1-ylsulfonyl)biphenyl-4-yl)methyl)propan-1-amine (PF-04455242; a highly selective KOR-antagonist). Subsequently, the defensive burying behavior (DBB) and alcohol intake/preference paradigms were evaluated. RESULTS: SAL-A markedly increased burying time, the height of bedding, and alcohol consumption/preference in A-withdrawal, while slightly increased the height of bedding in A-näive rats. PF-04455242 decreased both burying and immobility duration, whereas increases latency to burying, frequency of rearing, and the number of stretches attempts with no action on alcohol intake/preference in A-withdrawal rats. CONCLUSIONS: In general, stimulation/blockade of KOR in A-withdrawal animals exert higher responses compared to A-naïve ones. SAL-A produced anxiety-like behaviors and increased alcohol consumption/preference, especially/solely in the alcohol-withdrawal condition, while PF-04455242 augmented exploration with no effects on alcohol intake/preference. Our findings suggest a possible pharmacologic hyperreactivity of the KOR in PAG during alcohol withdrawal.


Asunto(s)
Alcoholismo , Síndrome de Abstinencia a Sustancias , Ratas , Masculino , Animales , Receptores Opioides kappa/agonistas , Receptores Opioides kappa/metabolismo , Sustancia Gris Periacueductal , Ratas Wistar
6.
Anim Cogn ; 26(3): 1065-1072, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36809584

RESUMEN

The Novel Object Recognition task (NOR) is widely used to study vertebrates' memory. It has been proposed as an adequate model for studying memory in different taxonomic groups, allowing similar and comparable results. Although in cephalopods, several research reports could indicate that they recognize objects in their environment, it has not been tested as an experimental paradigm that allows studying different memory phases. This study shows that two-month-old and older Octopus maya subjects can differentiate between a new object and a known one, but one-month-old subjects cannot. Furthermore, we observed that octopuses use vision and tactile exploration of new objects to achieve object recognition, while familiar objects only need to be explored visually. To our knowledge, this is the first time showing an invertebrate performing the NOR task similarly to how it is performed in vertebrates. These results establish a guide to studying object recognition memory in octopuses and the ontological development of that memory.


Asunto(s)
Octopodiformes , Reconocimiento en Psicología , Animales , Conducta Exploratoria , Percepción Visual , Reconocimiento Visual de Modelos
7.
Cell Mol Neurobiol ; 43(4): 1453-1468, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35902460

RESUMEN

Serotonin 5-hydroxytryptamine (5-HT) is a key neurotransmitter for the modulation and/or regulation of numerous physiological processes and psychiatric disorders (e.g., behaviors related to anxiety, pain, aggressiveness, etc.). The periaqueductal gray matter (PAG) is considered an integrating center for active and passive defensive behaviors, and electrical stimulation of this area has been shown to evoke behavioral responses of panic, fight-flight, freezing, among others. The serotonergic activity in PAG is influenced by the activation of other brain areas such as the medial hypothalamus, paraventricular nucleus of the hypothalamus, amygdala, dorsal raphe nucleus, and ventrolateral orbital cortex. In addition, activation of other receptors within PAG (i.e., CB1, Oxytocin, µ-opioid receptor (MOR), and γ-aminobutyric acid (GABAA)) promotes serotonin release. Therefore, this review aims to document evidence suggesting that the PAG-evoked behavioral responses of anxiety, panic, fear, analgesia, and aggression are influenced by the activation of 5-HT1A and 5-HT2A/C receptors and their participation in the treatment of various mental disorders.


Asunto(s)
Sustancia Gris Periacueductal , Serotonina , Humanos , Sustancia Gris Periacueductal/fisiología , Emociones , Ansiedad , Núcleo Dorsal del Rafe
8.
J Glob Antimicrob Resist ; 29: 462-467, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34788689

RESUMEN

OBJECTIVES: Ecuador is a lower-to-middle-income country not yet adherent to World Health Organization (WHO) antibiotic stewardship strategies, and data regarding basic metrics are still lacking. METHODS: We conducted a retrospective study of an antibiotic stewardship programme (ASP) consisting of restrictive measures on carbapenem dispensing pending required pre-authorisation and expert audit. We evaluated antibiotic consumption and its relationship to carbapenem resistance at a 610-bed, tertiary-level hospital in Quito, Ecuador. We used prescription data from 2010-2017 and converted them into defined daily doses (DDD). We then correlated these findings with the nature of service provided and antibiotic resistance data from the microbiology laboratory. We used descriptive statistics and interrupted time series (ITS) analysis. RESULTS: Throughout the study period, we analysed 16 984 355 prescriptions of 8 191 418.57 g of antibiotics (5 760 479.37 DDD). The in-hospital mean antibiotic prescription rate was 148.8 ± 14.8 DDD/100 occupied bed-days and 293.5 ± 65.3 DDD/100 occupied bed-days in the ICU. First-, second- and third-line antibiotic consumption was 38%, 52% and 10%, respectively. Our hospital data showed a high rate of antibiotic prescription in all hospital areas, mainly broad-spectrum antibiotics. Regarding the ASP introduced in 2016, ITS analysis showed a change in the outcome level immediately following the introduction for imipenem [-3.97; 95% confidence interval (CI) -5.31 to -2.61] but not for meropenem (0.66; 95% CI -0.37 to 1.71). CONCLUSION: Although our institution's ASP was successful in reducing imipenem consumption, a more embracing plan is required for further interventions to avoid unexpected effects.


Asunto(s)
Antibacterianos , Programas de Optimización del Uso de los Antimicrobianos , Antibacterianos/uso terapéutico , Carbapenémicos/uso terapéutico , Ecuador , Imipenem , Estudios Retrospectivos , Centros de Atención Terciaria , Organización Mundial de la Salud
9.
Parasitol Int ; 85: 102438, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34400350

RESUMEN

Parasites of the genus Eimeria are involved in the neonatal diarrhea complex of alpaca (Vicugna pacos) crias, and infection by Eimeria is commonly known as coccidiosis. There are limited reports of these protozoa in clinically asymptomatic crias. In this study, fecal samples from 78 clinically asymptomatic alpaca crias were analyzed to evaluate the prevalence, parasitological load, and diversity of Eimeria species. This study was conducted in the Quenamari community located in the Peruvian Andes (Marangani, Cuzco) at 4500 m above sea level. All fecal samples were examined for parasites using the quantitative McMaster and modified Stoll techniques. Microscopic examination showed the presence of Eimeria oocysts in 68 out of the 78 samples (87.18%). Among the 78 samples we found E. lamae in 67 (85.90%), E. punoensis in 49 (62.82%), E. alpacae in 42 (53.85%), E. macusaniensis in 32 (41.03%), and E. ivitaensis in four (5.13%). Regarding parasitized crias, overall there was a mean parasitological load of 43,920 oocysts per gram of feces (OPG). Eimeria lamae had the highest parasitological load (mean 206,600 OPG). These findings could be due to environmental contamination with oocysts of different Eimeria species. Additional research is needed to determine if this burden of coccidiosis could produce subclinical impacts to the health of alpaca crias.


Asunto(s)
Camélidos del Nuevo Mundo , Coccidiosis/veterinaria , Diarrea/veterinaria , Animales , Coccidiosis/epidemiología , Coccidiosis/parasitología , Diarrea/epidemiología , Diarrea/parasitología , Eimeria , Heces/parasitología , Femenino , Masculino , Oocistos/aislamiento & purificación , Perú/epidemiología , Prevalencia
10.
Int. j. med. surg. sci. (Print) ; 8(2): 1-10, jun. 2021. tab
Artículo en Inglés | LILACS | ID: biblio-1284419

RESUMEN

Introduction.Thyroid cancer is currently the first most common cancer in women in Ecuador. This study aimed to assess the changes in clinical presentation and diagnosis of differentiated thyroid cancer at a third level hospital in Quito, Ecuador.Methods and Materials.This is a retrospective case series performed in three consecutive periods from 1990 to 2019 at a tertiary level hospital, in Quito, Ecuador. The clinical records of 875 patients who had been diagnosed and surgically treated for differentiated thyroid cancer were reviewed. Demographic, clinical, imaging, and pathological data were collected and analyzed.Results. Significant trends toward older age, higher educational level, less palpable primary tumors, less palpable neck nodes, less distant metastases, more ultrasound, tomography and cytology exams, smaller primary tumors, more stage I patients, and more histological variant description, were found. Introduction.Thyroid cancer is currently the first most common cancer in women in Ecuador. This study aimed to assess the changes in clinical presentation and diagnosis of differentiated thyroid cancer at a third level hospital in Quito, Ecuador.Methods and Materials.This is a retrospective case series performed in three consecutive periods from 1990 to 2019 at a tertiary level hospital, in Quito, Ecuador. The clinical records of 875 patients who had been diagnosed and surgically treated for differentiated thyroid cancer were reviewed. Demographic, clinical, imaging, and pathological data were collected and analyzed.Results. Significant trends toward older age, higher educational level, less palpable primary tumors, less palpable neck nodes, less distant metastases, more ultrasound, tomography and cytology exams, smaller primary tumors, more stage I patients, and more histological variant description, were found.


Introducción. El cáncer de tiroides es actualmente el cáncer más frecuente en la mujer en Ecuador. El presente estudio ha tenido como objetivo evaluar los cambios en la presentación clínica y el diagnóstico del cáncer diferenciado de tiroides en un hospital de tercer nivel de Quito, Ecuador. Material y Métodos. El presente es un estudio retrospectivo de casos realizado en tres períodos consecutivos desde 1990 a 2019 en un hospital del tercer nivel en Quito, Ecuador. Los expedientes clínicos de 875 pacientes tratados quirúrgicamente por un cáncer diferenciado de tiroides fueron revisados. Los datos demográficos, clínicos, de imagen y patología fueron extraídos y analizados. Resultados. Se encontraron tendencias significativas hacia una edad más avanzada, nivel educativo más alto, menos tumores palpables, menos adenopatías regionales palpables, menos metástasis a distancia, más exámenes de ultrasonido y tomografía, más estudios de citología, más tumores pequeños y pacientes con estadío I y más descripciones de las variantes histológicas. Conclusiones. El cáncer de tiroides no sólo que ha aumentado continuamente en su frecuencia en los años recientes, sino que la presentación clínica, el manejo diagnóstico y terapéutico ha cambiado significativamente en las tres últimas décadas.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/epidemiología , Factores de Tiempo , Neoplasias de la Tiroides/patología , Evolución Clínica , Demografía , Estudios Retrospectivos , Autoexamen , Ecuador/epidemiología , Centros de Atención Terciaria
11.
Parasitology ; : 1-6, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-35260216

RESUMEN

Sarcoptic mange is a disease caused by an infectious parasite in the vicuñas (Vicugna vicugna) from South America. Although molecular studies have provided much information about the epidemiology of this disease, this information is still unknown in vicuñas. This study determined the prevalence and molecular characterization of Sarcoptes scabiei from vicuñas from Southern Peruvian Andes. During the 2018 shearing season, 181 vicuñas were clinically evaluated for lesions compatible with mange. Sarcoptes scabiei was detected in 35 (19.3%) vicuñas, and 50 mites from 25 vicuñas were selected for molecular analyses of the mitochondrial (cox1) and nuclear (ITS2) genetic markers. Molecular analyses of the cox1 and ITS2 sequences showed an identity of 94­99% and 99.8­100% with previous S. scabiei sequences registered in the GenBank, respectively. Sequence polymorphisms were more evident in the ITS2 than in the cox1, but only the cox1 had an association with the host. Phylogenetic analysis of S. scabiei cox1 sequences from vicuñas showed a cluster with S. scabiei cox1 sequences from canids, suggesting that the origin of S. scabiei from vicuña is associated with canid mites. This research is the first molecular analysis of S. scabiei from vicuñas. Future molecular studies will be necessary to determine the species variety, geographic segregation and host­parasite adaptation for this vicuña's mite.

12.
Acta investigación psicol. (en línea) ; 10(2): 17-26, abr. 2020. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1152710

RESUMEN

Abstract Stress is conceptualized as a systemic response triggered by a stimulus potentially harmful to an organism. Instead of an adaptive outcome, life-threatening experiences may contribute to the development of anxiety disorders and depression. Predator scent stress (PSS) is one of the most utilized rodent models of stress-induced psychopathology, in which rodents are exposed to a volatile predator cue that signifies imminent danger. It is unclear if the duration of a life-threatening experience could have differential consequences on the expression of anxiety-like and depression-like behaviors. For this reason, the goal of this present study was to evaluate the effect of different exposure durations (3 min., 10 min., or 20 min.) to the scent of bobcat urine. Wistar rats housed under 12/12 dark cycle in standard laboratory conditions were exposed to the PSS model and 24 hrs. after the stressor, behavioral consequences were evaluated in the open field test, saccharin preference test, and forced swim test. The results obtained show that a 10-minute exposure is sufficient to induce an anxiety-like and a depression-like behavioral profile. We conclude that the time exposure could be a major variable to obtain clear and trustable results and to avoid overexposure to stressor.


Resumen El estrés es una respuesta sistémica desencadenada por un estímulo potencialmente peligroso para el organismo. Esta respuesta permite al organismo adaptarse a la condición estresante, sin embargo, experiencias que amenazan a la vida pueden incrementar el riesgo de desarrollar trastornos de ansiedad y depresión. La exposición al olor de depredador (EOD) es el modelo animal de patología inducida por estrés más utilizado. Consta de la exposición a una pista olfativa que significa peligro inminente. Aún no está claro si la duración a una experiencia que amenaza la vida puede generar diferencias en la expresión conductas tipo-ansiedad o tipo-depresión. Por esta razón, el objetivo de este estudio fue evaluar el efecto de diferentes duraciones de exposición (3 min., 10 min. o 20 min.) al aroma de lince. Se utilizaron ratas hembra de la cepa Wistar en un ciclo luz oscuridad 12/12 en condiciones estándar de laboratorio, los sujetos fueron evaluados en la prueba de campo abierto, preferencia de sacarina y nado forzado 24 hrs. después de terminado el estresor. Los resultados indican que la exposición a 10 min. es suficiente para inducir el perfil conductual tipo-depresión y tipo-ansiedad. Concluimos que el tiempo de exposición puede ser una variable de mayor importancia para obtener resultados confiables y prevenir exposiciones innecesarias al estrés.

13.
Pap. avulsos Zool. ; 59: e.20195960, Nov. 28, 2019. ilus, tab
Artículo en Inglés | VETINDEX | ID: vti-24680

RESUMEN

Eight species of macaw (Psittacidae: Anodorhynchus, Ara, Primolius) have previously been reported from Paraguay. We discuss all verifiable reports of the species from Paraguay and provide comment on their statuses. Ara chloropterus and Primolius auricollis are both widespread species known from multiple reports across a wide geographic area. We report minor range extensions within Paraguay for both species. Anodorhynchus hyacinthinus is documented as a breeding resident with a restricted distribution in the Upper Paraguay River basin. The first modern records of Ara ararauna and the first record of Diopsittaca nobilis for the country are documented with photographs. We are unable to find any confirmed records of Anodorhynchus glaucus from Paraguay and thus consider it of possible occurrence. Two species are rejected as erroneously cited, Ara militaris and Ara glaucogularis. Consequently six species in four genera are now confirmed to occur in Paraguay.(AU)


Asunto(s)
Animales , Distribución Animal , Especificidad de la Especie , Loros/clasificación , Brasil
14.
Pap. avulsos zool ; 59: e.20195960, 25 mar. 2019. ilus, tab
Artículo en Inglés | VETINDEX | ID: biblio-1487186

RESUMEN

Eight species of macaw (Psittacidae: Anodorhynchus, Ara, Primolius) have previously been reported from Paraguay. We discuss all verifiable reports of the species from Paraguay and provide comment on their statuses. Ara chloropterus and Primolius auricollis are both widespread species known from multiple reports across a wide geographic area. We report minor range extensions within Paraguay for both species. Anodorhynchus hyacinthinus is documented as a breeding resident with a restricted distribution in the Upper Paraguay River basin. The first modern records of Ara ararauna and the first record of Diopsittaca nobilis for the country are documented with photographs. We are unable to find any confirmed records of Anodorhynchus glaucus from Paraguay and thus consider it of possible occurrence. Two species are rejected as erroneously cited, Ara militaris and Ara glaucogularis. Consequently six species in four genera are now confirmed to occur in Paraguay.


Asunto(s)
Animales , Distribución Animal , Especificidad de la Especie , Loros/clasificación , Brasil
15.
J Healthc Eng ; 2018: 1930357, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30245783

RESUMEN

The modelling of virtual environments and scenarios is an important area of research for the development of new computer-assisted systems in the areas of engineering and medicine, particularly in the area of biomechanics and biomedical engineering. One of the main issues while designing a virtual environment is the level of realism, which depends on the computing capacity and the level of accuracy and usefulness of the generated data. Thus, the dilemma is between the aesthetic realism and the information utility. This paper proposes a methodology to develop low-cost and high-quality virtual environments and scenarios for computer-aided biomedical applications. The proposed methodology is based on the open-source software Blender and the Visualization Toolkit libraries (VTK). In order to demonstrate the usability of the proposed methodology, the design and development of a computer-assisted biomedical application is presented and analysed.


Asunto(s)
Ingeniería Biomédica/métodos , Programas Informáticos , Cirugía Asistida por Computador/métodos , Realidad Virtual , Femenino , Humanos , Imagenología Tridimensional , Masculino , Cirugía Bucal
16.
J Healthc Eng ; 2018: 8783642, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29854368

RESUMEN

Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee.


Asunto(s)
Biomimética/métodos , Prótesis de la Rodilla , Rodilla/fisiología , Diseño de Prótesis/métodos , Procesamiento de Señales Asistido por Computador , Adulto , Fenómenos Biomecánicos/fisiología , Análisis de la Marcha , Humanos , Masculino , Adulto Joven
17.
Acta investigación psicol. (en línea) ; 8(1): 61-71, abr. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-949478

RESUMEN

Resumen: El estrés produce la sobreactivación del eje HPA y sistema neuroendocrino. Se ha mostrado que existe daño en estructuras relacionadas con el procesamiento emocional (amígdala) aprendizaje (hipocampo), toma de decisiones y prospección (corteza prefrontal). Sin embargo, se generalizan los efectos del estrés sin ponderar el tipo de estrés (crónico o agudo), duración, especie, etc. Esto permite que hallazgos se contrapongan a nivel cortical, neuroquímico, hormonal y conductual. El objetivo fue evaluar los efectos del estrés crónico impredecible (ECI) en diferentes cepas de ratas y sus efectos inmediatos o a largo plazo. Se utilizaron ratas macho Wistar, Wistar Kyoto y SHR en condiciones estándar de laboratorio. Se aplicó una batería de ECI y una batería de evaluación conductual para evaluar efectos previos, agudos y crónicos. La cepa Wistar Kyoto muestra deficiencias previas a la exposición. La cepa SHR muestra mayor movilidad y sesgos atencionales, lo que produce un efecto que perdura a largo plazo. La cepa Wistar muestra una gran capacidad de adaptación ya que aunque se observaron deficiencias inmediatamente después de la exposición al estrés, éstas se recuperan e largo plazo. Se infiere que las precondiciones de los sujetos podrían funcionar como biomarcadores y poder prevenir padecimientos relacionados al estrés.


Abstract: Stress produces the over activation of the Hypothalamus Pituitary Adrenal axis (HPA) and the neuroendocrine system. It has been shown that it could damage structures related with the emotional processing (amygdala), learning and memory (Hippocampus), decision making and prospection (prefrontal cortex). However, the stress affects are generalized without weighting all the elements related with this conditions, for example the kind of stress stimuli (acute or chronic), duration, species, etc. This allowed that some findings it will go against each other in relation to cerebral cortex function, neurochemical, hormonal and behavioral. The main porpoise of this research was to evaluate the effects of the unpredictable chronic stress on several rat strains (Wistar, Wistar Kyoto and SHR) and its immediate effects or in long term so. Wistar, Wistar Kyoto and SHR rats were used. All animals were housed in standard laboratory conditions and we follow the international guide for use and care of laboratory animals. The subjects were exposed to the Chronic Unpredictable Stress Battery (CUSB) and to evaluate the stress effects all the subjects were evaluated with a Battery of Behavioral Evaluation to find the previous, immediate or the long-term effects of CUSB exposition. The Wistar Kyoto strain showed deficits before the stress exposure. Whereas the SHR rats showed more mobility and poor attention which produces a long-term effect. The Wistar strain show a high adaptation to the adverse conditions because until the animals showed strong effects immediately after the stress exposure they showed a good recovery in the long term. In conclusion we can asseverate that the preconditions in every strain plays a major role in the stress response and that preconditions it could be used as biomarkers and in that way infer if the subjects are more susceptible to suffer high stress or some other related disease.

18.
Rev. mex. ing. bioméd ; 38(2): 437-457, may.-ago. 2017. graf
Artículo en Inglés | LILACS | ID: biblio-902363

RESUMEN

ABSTRACT: This paper presents the analysis of human gait of three young adults under several walking conditions similar to those in real life. The aim is to evaluate how the human gait varies when different walking conditions are considered. In order to evaluate the human gait variations under different walking conditions, first a 3D computer visión system to reconstruct human gaits is developed and presented. Then, a set of kinematic gait parameters is defined in order to analyse the different gait patterns. Finally, several experiments are conducted with three normal Young adults walking under different real-life conditions, such as ascending a slope walk, no arm-swing walk, carrying a front load walk, carrying a lateral load walk, fast walk and high-heel shoes walk. The results has shown that the human gait pattern vary according to the walking conditions, being the most common variation a slower walk with shorter steps than the normal walk. Since the aim of the paper is to identify and evaluate human gait variations under different walking conditions, only three subjects were considered in the study. However, in order to provide more precise and standard results the number of subjects must be increased considering different age, height, sex, weight, and health conditions of the participants. Human walking patterns are very important for medical diagnosis and orthopedics, pathological and aging evaluation, medical rehabilitation, and design of rehabilitation systems, human prosthesis and humanoid robots. However, most of the research work in the literature has been primarily focused on the analysis of gait patterns under normal walking conditions. This fact has led to a limited knowledge of the human gait patterns since real-life walking conditions are diverse, e.g. walking carrying a load. This paper presents the analysis of human gait of three young adults under walking conditions similar to those in real life. Human gait patterns vary with the walking conditions, which must be considered during the analysis, evaluation and diagnosis of gait performance, or during the design process of prostheses or rehabilitation systems.


RESUMEN: En este artículo se presenta el análisis del patrón de caminado de tres adultos jóvenes bajo diversas condiciones de caminado tal como se presentan en la vida real. El objetivo es determinar la variación del patrón de caminado cuando se tienen diferentes condiciones de caminado. Con el propósito de evaluar la variación del patrón de caminado bajo diversas condiciones de caminado, primero se desarrolla y presenta un sistema de visión por computadora para la reconstrucción 3D de las trayectorias del caminado humano. Posteriormente se define un conjunto de parámetros cinemáticos de caminado para analizar los diferentes patrones de caminado. Finalmente se realiza una serie de experimentos con tres adultos jóvenes a los cuales se les pidió caminar bajo diferentes condiciones como en la vida real, tales como caminar subiendo una pendiente, caminar sin braceo, caminar sosteniendo una carga la frente, caminar sosteniendo una carga lateral, caminar rápido y caminar con zapato de tacón alto. Los resultados han demostrado que el patrón de caminado humano varía de acuerdo a las condiciones del caminado, siendo una de las variaciones más comunes un caminado más lento con pasos más cortos que el caminado normal. Debido a que el objetivo del trabajo es identificar y evaluar variaciones del patrón de caminado bajo diversas condiciones, solamente se consideraron tres sujetos de estudio. Sin embargo, para proporcionar resultados más precisos y normalizados el tamaño de la muestra debe incrementarse considerando diferentes edades, estaturas, sexo, peso, y condiciones de salud de los participantes. Los patrones del caminado humano son muy importantes para el diagnóstico médico y ortopédico, las evaluaciones patológicas y de envejecimiento, la rehabilitación médica, y el diseño de sistemas de rehabilitación, prótesis humanas y robots humanoides. Sin embargo, la mayoría de los trabajos de investigación reportados en la literatura se han enfocado principalmente en el análisis del patrón de caminado humano bajo condiciones normales de caminado. Estos estudios del caminado humano han dado lugar a un conocimiento limitado debido a que las condiciones del caminado en la vida real son diversas, por ejemplo caminar con una carga. Este trabajo presenta el análisis del patrón de caminado de tres adultos jóvenes bajo diversas condiciones de caminado similares a la vida real. El patrón de caminado humano varía de acuerdo a las condiciones de caminado, lo cual debe ser considerado durante en análisis, evaluación y diagnóstico del desempeño de caminado, o durante el proceso de diseño de prótesis o sistemas de rehabilitación.

19.
GEN ; 71(1): 25-27, mar. 2017. ilus, graf
Artículo en Español | LILACS | ID: biblio-892300

RESUMEN

Los cuerpos extraños en el medio médico, constituyen un problema clínico frecuente, que es más común en niños, sin embargo también se observa en adolescentes y adultos. Se presenta un caso de una paciente de 16 años quien en estado de embriaguez, ingirió involuntariamente cuerpo extraño (chapa de cerveza),presentando dos días después disfagia y odinofagia. Para su extracción se utilizó sobretubo de diseño local que facilitó y simplificó, el paso del cuerpo ext raño por las zonas de resistencia natural del cardias y esófago cervical.


The foreign bo dies in our region are a frequent clinical problem. It is most frequent in children but also observed in adolescents and adults. We present a case of a patient of 16 years old. She was drunk and involuntarily swallowed foreign body ( beer cap ). She presente d two days later dysphagia and odynophagia. For endoscopic extraction, we use local design overtube which make easier endoscopic procedure and simplified the passage of the foreign body by the natural resistance of the Cardia and esophagus cervical areas.

20.
Rev. peru. biol. (Impr.) ; 23(3): 347-350, Sept.-Dec. 2016. ilus
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1094282

RESUMEN

Rufous-tailed Jacamar Galbula ruficauda is known from few records in Paraguay, all during the last 20 years. The species has been recorded in the northern Chaco and Paraguayan Pantanal, with all confirmed records from Alto Paraguay department. Here we summarise all reports and localities of the species in Paraguay to date. The species is categorized as Data Deficient at the national level, but may be more widely distributed than is currently recognised.


Galbula ruficauda es una especie que cuenta con pocos registros a lo largo de 20 años en Paraguay. La especie ha sido observada en la zona norte del Chaco y Pantanal paraguayo, departamento Alto Paraguay. En este trabajo reportamos los registros y localidades de ocurrencia de la especie en el país. Actualmente se encuentra en la categoría de Datos Insuficientes a nivel nacional, aunque puede ser que su distribución sea más amplia.

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