Search results for "ratón"
showing 10 items of 64 documents
Análisis de la interacciones parásito-hospedador en el modelo Echinostoma caproni-roedor, con énfasis en los factores que determinan el curso de la i…
2015
En la presente Tesis Doctoral se analizan diferentes parámetros implicados en las relaciones parásito-hospedador en helmintiasis intestinales mediante la utilización del modelo experimental Echinostoma caproni-roedor. Con esta finalidad se estudian diversos aspectos inmunológicos, además de las alteraciones intestinales inducidas por la infección en dos sistemas parásito-hospedador: E. caproni-ratón y E. caproni-rata. Los resultados obtenidos ponen de manifiesto que el IFN-γ y el óxido nítrico son mediadores fundamentales en el desarrollo de infecciones crónicas en ratón, induciendo disfunción mitocondrial en las células del epitelio intestinal e hiperplasia tisular. No obstante, se sugiere…
The nature of host tissue destruction in tumor invasion
1986
The nature of host tissue destruction in tumor invasion was investigated in experimentally induced carcinomas and sarcomas, xenografted into skeletal muscle. By means of light and electron microscopy it was shown that in both carcinomas and sarcomas the confrontation of host tissue with the invading tumor cells does not result in immediate destruction of host tissue but in a transitory state of coexistence which gradually proceeds to progressive host tissue atrophy. This process of progressive atrophy, which finally results in the total disappearance of the invaded host tissue, is considered to be caused mainly by the increasing pressure and competitive withdrawal of oxygen and nutrients by…
BDNF, but not NT-4, is necessary for normal development of Meissner corpuscles.
2005
Abstract Meissner corpuscles are rapidly adapting cutaneous mechanoreceptors depending for development on TrkB expressing sensory neurons, but it remains to be established which of the known TrkB ligands, BDNF or NT-4, is responsible of this dependence. In this study we analyze Meissner corpuscles in the digital pads of mice with target mutations in the genes encoding for either BDNF or NT-4, using immunohistochemistry and transmission-electron microscopy, and they were identified based on their morphology and expression of S100 protein. All wild-type animals as well as NT-4 −/− animals and BDNF and NT4 heterozygous animals have Meissner corpuscles that are normal in number and size. Howeve…
Rewarding Properties of Testosterone in Intact Male Mice
2000
The present study examined the rewarding properties of 4-androsten-17β-ol-3-one testosterone in intact male mice using the conditioned place preference (CPP) technique. In Experiment 1, the pharmacokinetics of 0.8 and 1.2 mg/kg of testosterone were studied to determine the most appropriate temporal interval to test behavior. Additionally, the locomotor activity was recorded to control a possible interfering effect on CPP. The maximum testosterone concentration was registered at 45 min of administration, and no effects on activity were found. In Experiment 2, three groups of male OF-1 mice received four pairings of the least-preferred compartment with testosterone (0.8, 1, or 1.2 mg/kg, SC) …
Long-Term Effects of Delayed Fatherhood in Mice on Postnatal Development and Behavioral Traits of Offspring1
2009
This study aims to analyze, in mice, the long-term effects of delayed fatherhood on postnatal development, spontaneous motor activity, and learning capacity of offspring. Hybrid parental-generation (F 0 ) males, at the age of 12, 70, 100, and 120 wk, were individually housed with a randomly selected 12wk-old hybrid female. The resulting first-generation (F 1 ) offspring were tested for several developmental and behavioral variables. Cumulative percentage of F 1 pups that attained immediate righting in the 120-wk group was lower than that found in the 12-, 70-, and 100-wk groups. Furthermore, the postnatal day of attaining immediate righting was higher in pups from the 120-wk group when comp…
Recombinant human erythropoietin increases the radiosensitivity of xenografted human tumours in anaemic nude mice
2001
Purpose: The effect of recombinant human erythropoietin (Epo) on the radiosensitivity of human tumour xenografts growing in anaemic nude mice was studied. Methods and materials: Anaemia was induced by total body irradiation (TBI) of mice prior to tumour transplantation. The development of anaemia was prevented by Epo (1000 U/kg s.c.) given 3 times weekly starting 2 weeks prior to TBI (5 Gy). Epo treatment did not influence the growth rate of the tumours, which were transplanted into the subcutis of the hind leg of mice. Thirteen days after TBI (tumour volume of approx. 40 mm3), a single-dose irradiation (12 Gy) of the tumour was performed resulting in a growth delay with subsequent regrowth…
In vivo delivery of human alpha 1-antitrypsin gene to mouse hepatocytes by liposomes.
1993
The pTG7101 plasmid containing the full length human alpha 1-Antitrypsin was encapsulated in large (142 +/- 15 nm of diameter) and small (54 +/- 11 nm of diameter) liposomes and administered i.v. to mice (80 ng/mouse). Control animals were treated with empty (small and large) liposomes plus free DNA and with the liposome solvent buffer. The immunohistochemical results on liver cryosections and cytophotometric analysis of hepatocyte chromophore absorbance, after peroxidase reaction, indicated that significant presence of immunoreactive human alpha 1-antitrypsin was present 7 days after mice treatment with encapsulated DNA in small liposomes but not when large liposomes were used. This effect…
Induction of hapten-specific tolerance by interleukin 10 in vivo.
1994
Interleukin 10 (IL-10) is released during the induction phase of contact sensitivity and was shown in prior functional studies to convert epidermal Langerhans cells (LC) from potent inducers of primary immune responses to specifically tolerizing cells in vitro. To investigate whether IL-10 also subserves the function of a tolerizing agent in vivo ears of BALB/c or C3H mice were injected intradermally with 1-2 micrograms of recombinant mouse (rm)IL-10 8 h before epicutaneous application of 3% trinitrochlorobenzene (TNCB; a contact allergen). As a control, mice were injected with phosphate-buffered saline or IL-10 plus neutralizing amounts of anti-IL-10 mAb. 5 d later, mice were challenged wi…
Effcts of Dextran Sulphate (Dxs) on Lymphocyte Localization in Complement-Deficient Mice: Evidence that the Fifth Component of Complement is not Impl…
1984
AbstractThe effects of subcutaneously or intraperitoneally administered dextran sulphate (DXS) (5nmg/kg) on the subseguent 1 h localization of intravenously injected radiolabelled lymph node cells was investigated in complement deficient mice which lack C5.DXS proved to be equally as potent in depressing cell localizzation in deficient as compared to normal mice. These findings. indicate that the terminal complement components are not, essential for DXS activity.
DNA damage susceptibility and repair in correlation to calendric age and longevity.
2000
In two mouse strains, SAM P (senescence acceleration prone) and SAM R (senescence acceleration resistant), of different longevities, with a ratio of P/R=1:2), the DNA status in the course of aging has been investigated using the DNA Alkaline Filter Elution (AFE) technique. Six different organs (brain, liver, heart, lung, intestine, and muscle) have been used in each of the four animals of a given age. Earlier it had been shown, that DNA is damaged the more the higher the age of the animal. DNA damage susceptibility, measured after exposure of organ pieces to nitroquinoline-N-oxide (NQO), is also significantly increased at higher ages, while repair, measured of NQO damaged tissue after 3 h i…