Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Behav Processes ; 100: 74-81, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23954831

RESUMEN

Pectoral fin contact in bottlenose dolphins represents one form of tactile communication. Acoustic communication associated with pectoral fin contact is an additional level of communication that may change or enhance the tactile message between two individuals. In this study, we examine vocalization types associated with pectoral fin contact in a group of captive bottlenose dolphins (Tursiops truncatus). From 2006 to 2009, vocalizations potentially associated with 748 pectoral fin contacts were examined: whistles, click trains and overlap of whistles and click trains were documented when associated with fin contact. Dolphins were also documented not vocalizing when exchanging pectoral fin contacts. Call type associated with pectoral fin contact was compared for the proportion of the type of pectoral fin contact, vocalizer sex, initiator and receiver roles, and gender pair. Overall, vocalizations differed significantly by vocalizer role as rubber or rubbee, initiator, and sex. Receivers and rubbees clicked and used overlap vocalizations more frequently, and males produced overlap vocalizations more frequently. These results suggest that whistles may be used to initiate pectoral fin contact or show preference for a particular partner, while click trains may be used to show disinterest in pectoral fin contact or to signal the end of a contact. Examining vocalizations produced in conjunction with tactile contact is a relatively new approach in the study of individual dolphin behavior and may be useful for understanding dolphin social alliances and social preferences for various individuals within a population.


Asunto(s)
Aletas de Animales/fisiología , Delfín Mular/fisiología , Tacto/fisiología , Vocalización Animal/fisiología , Animales , Conducta Animal/fisiología , Femenino , Masculino
2.
Artículo en Inglés | MEDLINE | ID: mdl-19757233

RESUMEN

Living cells encapsulated in polymeric shells are receiving increasing attention because of their possible biotechnological and biomedical applications. The aim of this work is to evaluate how different polyelectrolyte coatings, characterized by different numbers of polyelectrolyte layers and by different polyelectrolyte conformations, affect the viability of encapsulated biological material. We demonstrate the ability to individually encapsulate HL-60 cells as well as rat pancreatic islets within polymeric shells consisting of different PE layers using the layer-by-layer process. Coating of HL-60 cells allows for surviving and functioning of cells for all applied PE as well as for different numbers of layers. The islets encapsulated in applied polyelectrolytes exhibited the lower level of mitochondrial activity as compared to non-encapsulated islets. Nevertheless, encapsulated islets exhibited comparable absorbance values during the whole period of culture. Polyelectrolyte coating seems to be a promising way of allowing capsule void volume minimization in a model of encapsulated biological material for local production of biologically active substances.


Asunto(s)
Células/metabolismo , Electrólitos/química , Electrólitos/metabolismo , Polímeros/química , Polímeros/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Células/citología , Células/efectos de los fármacos , Electrólitos/toxicidad , Células HL-60 , Humanos , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Células Jurkat , Microscopía de Fuerza Atómica , Conformación Molecular , Nanocápsulas/química , Polímeros/toxicidad , Ratas
3.
Eur J Med Res ; 14 Suppl 4: 53-8, 2009 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-20156726

RESUMEN

Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.


Asunto(s)
Hidrocéfalo Normotenso/cirugía , Equilibrio Postural , Derivación Ventriculoperitoneal , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hidrocéfalo Normotenso/fisiopatología , Masculino , Persona de Mediana Edad , Visión Ocular
4.
J Physiol Pharmacol ; 59 Suppl 6: 201-7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19218644

RESUMEN

Gait and body balance disturbances are important clinical problems in patients with normal pressure hydrocephalus (NPH). They affect patients' locomotion and lead to a higher risk of falls. The gait pattern may be described as durations of the single and double support and of a stance phase. The aim of the present study was to apply the pattern recognition methods for the evaluation of gait disturbances in patients with NPH before and after neurosurgical treatment (shunt implantation). The results indicate that the parameters measured with a Computer DynoGraphy (CDG) system may effectively differentiate changes of gait in patients with NPH.


Asunto(s)
Trastornos Neurológicos de la Marcha/diagnóstico , Hidrocéfalo Normotenso/diagnóstico , Anciano , Algoritmos , Diagnóstico por Computador , Femenino , Trastornos Neurológicos de la Marcha/etiología , Humanos , Hidrocéfalo Normotenso/complicaciones , Hidrocéfalo Normotenso/cirugía , Locomoción/fisiología , Masculino , Persona de Mediana Edad , Reconocimiento de Normas Patrones Automatizadas , Equilibrio Postural/fisiología , Resultado del Tratamiento , Derivación Ventriculoperitoneal
5.
Transplant Proc ; 39(9): 2914-6, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18022015

RESUMEN

Implantable bioartificial liver has been investigated for patients suffering from liver insufficiency after mass liver resection or acute liver failure. Liver cells are implanted as free cell suspension, in microencapsulation systems or using microcarriers. To exhibit their typical functions, hepatic cells need a three-dimensional environment that is much more physiological than a flat one. The aim of our study was in vivo evaluation of spongy polyethersulfone membranes as a synthetic support for hepatic cells grown three dimensionally and transplanted to SCID/NOD mice. Spongy membranes were prepared using phase inversion from membrane-forming mixtures containing the following: polyethersulfone (based polymer), dimethylformamide (solvent), polyvinylpyrrolidone MW 10000 (small pore precursor), and cellulose (large pore precursor). We observed that polyethersulfone membranes were well tolerated by C3A cells and we did not observe any toxic effect, resulting in viability of cells >95%. Use of collagen gel as a support for cells on the scaffold gives the opportunity to increase 10 times the number of cells seeded on the membrane. Heparin addition to collagen gel did not influence albumin production in SCID/NOD mice. We observed an increase of albumin production after 7 and 14 days after implantation. Use of collagen gels in combination with polymer scaffolds allows preparation of bioartificial organs possessing high cell concentration for transplantation purposes.


Asunto(s)
Trasplante de Células/métodos , Hepatocitos/citología , Animales , Técnicas de Cultivo de Célula/métodos , Colorantes , Hepatopatías/terapia , Membranas Artificiales , Ratones , Ratones Endogámicos NOD , Polímeros , Sulfonas
6.
Stain Technol ; 65(3): 113-8, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1696034

RESUMEN

A combined method for clearing soft tissues, staining cartilage and bone, and injecting the vascular system of small mammals was developed using Mus musculus (house mouse). Mammalian muscle tissue remains milky or even opaque after "clearing" by previous techniques due to the relatively high content of intramuscular fat. A method employing chloroform-ethanol successfully renders soft tissues of mammalian specimens translucent without damaging or bleeding color from the latex injected in the circulatory system. Resulting specimens yield an excellent view of the skeletal system and the injected vascular system without obstruction by opaque tissues or disruption by physical removal of connective tissue.


Asunto(s)
Fijadores , Técnicas Histológicas , Látex , Coloración y Etiquetado/métodos , Animales , Vasos Sanguíneos/anatomía & histología , Huesos/anatomía & histología , Cartílago/anatomía & histología , Ratones
7.
Kardiol Pol ; 32 Suppl 2: 71-82, 1989.
Artículo en Polaco | MEDLINE | ID: mdl-2699340

RESUMEN

In the paper computer aided method is described which can be applied for scenario generation of the health care system for cardiovascular diseases treatment. The real life system is represented in the form of patient flows in the network of diagnostic and therapeutic medical services. The adequate computer system with certain requirements for input data is then prepared. The alternative projections can be automatically calculated and evaluated by the expert teams for scenario generation. Selected preliminary scenarios obtained for ischemic heart disease are presented.


Asunto(s)
Cardiología/tendencias , Enfermedades Cardiovasculares/terapia , Simulación por Computador , Planes de Sistemas de Salud/organización & administración , Modelos Cardiovasculares , Modelos Teóricos , Regionalización/organización & administración , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/prevención & control , Necesidades y Demandas de Servicios de Salud , Humanos , Polonia , Estados Unidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA