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1.
J Chem Phys ; 140(22): 224319, 2014 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-24929400

RESUMEN

The photochemistry of glycolaldehyde (GA) upon irradiation at 266 nm is investigated in argon, nitrogen, neon, and para-hydrogen matrices by IR spectroscopy. Isomerization and fragmentation processes are found to compete. The hydrogen-bonded Cis-Cis form of GA is transformed mainly to the open Trans-Trans conformer and to CO and CH3OH fragments and their mixed complexes. Different photo-induced behaviours appear depending on the matrix. In nitrogen, small amounts of Trans-Gauche and Trans-Trans conformers are detected after deposition and grow together upon irradiation. The Trans-Gauche conformer is characterized for the first time. In para-hydrogen due to a weaker cage effect additional H2CO and HCO fragments are seen. Calculations of the potential energy surfaces of S0, S1, and T1 states--to analyse the torsional deformations which are involved in the isomerization process--and a kinetic analysis are presented to investigate the different relaxation pathways of GA. Fragmentation of GA under UV irradiation through the CO+CH3OH molecular channel is a minor process, as in the gas phase.

2.
Lab Anim ; 43(3): 278-83, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19237456

RESUMEN

An interview study was carried out with the aim of clarifying the reasons for the limited use of phenotypic characterization of genetically-modified mice (GMM) and identifying issues hindering its implementation. A total of 15 users of GMM participated in semi-structured face-to-face interviews, which were audio-taped and transcribed. The results were extracted using content analysis by theme. The investigation confirmed that few animals were systematically phenotyped and an observational approach was found to be widespread. The primary interest of the interviewees was phenotyping for impaired animal welfare. The concept of phenotyping was widely understood and perceived as a scientific advantage. The comprehensiveness of the protocols and the resources required for phenotyping were seen as problematic. All participants addressed this issue, be it regarding lack of time, money or expertise. Also, among the negative statements were worries about the capability of the available protocols to produce the information needed by the individual scientist. Phenotyping was predicted to become much more widespread in the future and its success was expected to depend on the development of reliable, fast and inexpensive methods. The study identified different aims of phenotyping and the suitability of the published protocols for these purposes was discussed. The contradiction between the limited use of characterization and its advantages was also discussed and proposals for the improvement of future phenotyping strategies are formulated.


Asunto(s)
Animales Modificados Genéticamente , Entrevistas como Asunto , Monitoreo Fisiológico/estadística & datos numéricos , Fenotipo , Adulto , Bienestar del Animal/normas , Animales , Actitud , Humanos , Intención , Ratones , Persona de Mediana Edad , Modelos Animales , Monitoreo Fisiológico/normas
3.
Lab Anim ; 41(3): 301-11, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17640457

RESUMEN

The standardized nomenclature of rodent strains, genes and mutations has long been the focus of careful attention. Its aim is to provide proper designation of laboratory animals used in research projects and to convey as much information on each strain as possible. Since the development of different techniques to mutate the genome of laboratory rodents on a large scale, the correct application of current nomenclature systems is of increased significance. It facilitates not only the accurate communication of scientific results but is indispensable in controlling the dramatically increased number of transgenic animal models in experimental units, archives and databases. It is regrettable that many publications, especially on transgenic rodents, use vague and inappropriate strain designation. This situation should definitely be improved, particularly considering the increasingly emphasized importance of genetic background on the phenotype of mutations. The aim of these guidelines is to raise awareness about specific features of production and of the current nomenclature system used for transgenic rodents.


Asunto(s)
Animales Modificados Genéticamente , Animales de Laboratorio , Ratones/genética , Ratas/genética , Terminología como Asunto , Crianza de Animales Domésticos/métodos , Animales
4.
Lab Anim ; 38(1): 85-91, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14979993

RESUMEN

Renal epithelial proliferation has previously been found to be a common condition in a colony of Lewis x Brown Norway (BN) F2 hybrid rats. The aim of this study was to investigate the prevalence and clinical consequences of this condition in pure inbred BN and Lewis rats. Renal epithelial proliferation was found in 29 of 49 BN rats (59%) examined and in four of 50 Lewis rats (8%) examined. Serum creatinine and serum corticosterone was not influenced by the condition. Haematuria was more common in BN rats with (74%) than without renal papillary proliferation (35%, P < 0.05), but it may not be used to diagnose renal epithelial proliferation, as we found rats having renal epithelial proliferation without showing haematuria and rats showing haematuria without having renal epithelial proliferation. Haematuria was also common in Lewis rats (16-56% dependent of age and gender), in which renal epithelial proliferation were found in only 8%. Fluctuating asymmetry, which was used as a measure of developmental instability, was found to be increased in rats with renal epithelial proliferation (P < 0.05). Haematuria was also found to be related to the degree of fluctuating asymmetry (P < 0.01). Although the prevalence of renal epithelial proliferation is clearly higher in BN rats than in Lewis rats (P < 0.01), and although in previous reports the condition was found in F2 BN x Lewis hybrids and not in F1 BN x Lewis hybrids it cannot clearly be defined as having been caused by a single Mendelian gene, as we found it in both inbred strains. Futhermore, we found that morphologically the proliferations could be placed on the papillary as well as the medullary wall of the renal pelvis, while previously it has only been described on the papillary wall.


Asunto(s)
División Celular , Riñón/fisiología , Ratas Endogámicas BN , Enfermedades de los Roedores/patología , Animales , Epitelio/patología , Femenino , Hematuria/patología , Hematuria/veterinaria , Masculino , Ratas , Ratas Endogámicas Lew
5.
Lab Anim ; 37(1): 1-9, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12626067

RESUMEN

A thorough welfare evaluation performed as part of a general phenotype characterization for both transgenic and traditional mouse strains could not only contribute to the improvement of the welfare of laboratory animals, but could also be of benefit to scientists, laboratory veterinarians and the inspecting authorities. A literature review has been performed to identify and critically evaluate already existing protocols for phenotype and welfare characterization. There are several relevant schemes available, among others the SHIRPA method, the modified score sheet of Morton and Griffiths, the FRIMORFO phenotype characterization scheme and the behavioural phenotype schemes as described by Crawley. These protocols have been evaluated according to four goals: Their ability (1) to reveal any special needs or problems with a transgenic strain, (2) to cover the informational needs of the purchaser/user of the strain, (3) to refine the welfare of the transgenic animal model by identifying relevant humane endpoints, (4) to prevent the duplication of animal models that have already been developed. The protocols described are useful for characterizing the phenotype and judging welfare disturbances, however the total amount of information and the degree of detail varies considerably from one scheme to another. We present a proposal regarding the practical application of the various schemes that will secure proper treatment and the identification of humane endpoints. It is advocated that with every purchase of a particular strain, an instruction document should accompany the strain. This document needs to give detailed descriptions of the typical characteristics of the strain, as well as necessary actions concerning relevant treatment and humane endpoints. At the moment no such documents are required. The introduction of these types of documents will contribute to improvements in animal welfare as well as experimental results in laboratory animal experimentation.


Asunto(s)
Bienestar del Animal , Animales de Laboratorio , Ratones Transgénicos , Fenotipo , Crianza de Animales Domésticos , Animales , Conducta Animal , Modelos Animales de Enfermedad , Ratones , Enfermedades del Sistema Nervioso/genética
6.
Lab Anim ; 36(2): 193-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11943085

RESUMEN

Fluctuating asymmetry, which reflects small, random deviations from symmetry in otherwise bilaterally symmetrical characters, may be used as an indicator of developmental instability in humans and farm animals, and it may also be applicable as a stress indicator. We intended to find a method to allow the use of fluctuating asymmetry as a stress indicator in laboratory animals. That method had to be reproducible and reliable. Furthermore, its applicability in laboratory animals would be improved if it was possible to obtain measurements on the skin surface that correlated with results obtained by measuring the skeleton directly. Seven traits in mice and five traits in rats were evaluated for their applicability for measuring fluctuating asymmetry in mice and rats. Two out of the seven traits, i.e. the width of the joint between the third metatarsal bone and the digital bone on the hind paw, and the length of the incisor tooth at the top, were found to be reliable and reproducible for detecting fluctuating asymmetry in mice as well as in rats. Three out of the seven traits, i.e. the width of the carpal bones, the width of the joint between the tibia and the tarsal bones, and the length of the incisor tooth at the bottom, did express fluctuating asymmetry, but showed a poor day-to-day reproducibility. If the day-to-day reproducibility could be increased, these three traits might also be suitable for measuring fluctuating asymmetry in mice and rats. The last two traits, i.e. the length of ulna and the length of calcaneus plus metatarsal bone i.v., measured both on the skin surface and directly on the bone, did not express fluctuating asymmetry, and had a poor day-to-day reproducibility. These two traits are not suitable for measuring fluctuating asymmetry in mice and rats.


Asunto(s)
Tipificación del Cuerpo/genética , Variación Genética/genética , Genética de Población , Bienestar del Animal , Animales , Huesos/anatomía & histología , Biología Computacional/métodos , Monitoreo del Ambiente/métodos , Femenino , Masculino , Ratones , Ratones Endogámicos , Fenotipo , Ratas , Ratas Endogámicas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estrés Fisiológico/etiología , Estrés Fisiológico/genética , Estrés Fisiológico/fisiopatología
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