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Activity of spleen lymphocytes derived from T. spiralis-infected C3H/w mice in the local GvH reaction was assessed using the popliteal lymph node GvH assay. It was found that splenocytes obtained on day 10 of the infection were substantially more active in the reaction than the spleen cells collected from uninfected donors. This effect correlated inversely with the infectious dose of the parasite, i.e. cells obtained from mice infected with 500 larvae per mouse were less efficient stimulators of the GvH reaction than splenocytes isolated from mice infected with 200 larvae per mouse. On day 30 of the infection activity of spleen T cells in the GvH reaction was suppressed in comparison to the control splenocytes but on day 60 post infection this activity returned to the baseline level. The above variations in the activity of splenic T lymphocytes in the local GvH reaction were readily quantitated by comparison of the three appropriate parameters assessed in the popliteal lymph nodes of both the infected and control animals and expressed as the mass, cellularity, and proliferation coefficients, respectively.
In this report we present effect of pizotifen, an antagonist of serotonin (5-hydroxytryptamine; 5-HT) receptors, on P-induced convulsions in mice. Experiments were conducted on male mice Balby. Convulsive effect P was determined using the following measures: percentage of mice with seizures, the number of seizure episodes/2 h, the latency time of the beginning P-induced seizure activity in mice and P-induced seizure activity of mice determined by score of Racine. Pretreatment mice with pizotifen (0.5 mg/kg ip) did not prevent convulsive effect P, applied ip at the dose of 50 μmol/kg ip (59.3 mg/kg) but significantly shortened the latency time of the beginning of P-induced seizure activity of mice. We conclude that central serotonin receptors are involved in the mechanism of P-induced convulsions.
The immunomodulatory effect of two preparations from Panax ginseng radix, namely Ginsengcha (granulated mass of radix ginseng) and Ginsengpian (ginseng radix flakes) on mice has been investigated. The examined immune parameters were the following: the production of anti-SRBC antibodies, the chemokinesis of mouse spleen cells and the graft-versus-host reaction induced by mouse spleen cells. Additionally, the influence of ginseng preparations on the angiogenic activity of syngeneic LI sarcoma cells, LI sarcoma tumour growth and tumour blood supply (haemoglobin content) was examined. The production of antibodies was enhanced, particularly in the group with lower control parameters (pcO.OOl). Chemokinesis proved to be augmented (p<0.001) after 10 days of administering ginseng preparations to mice. The ability of mouse spleen cells to produce immunological mediators in the GvH reaction (immunological angiogenesis) turned out to increase significantly (p<0.001) under the influence of Ginsengcha. Neither Ginsengpian nor Ginsengcha stimulated the angiogenic activity of the LI sarcoma cells. Ginsengpian sligtly decreased this activity (p<0.02). The LI sarcoma tumour volume was significantly reduced by Ginsengcha (p<0.05), but no influence on tumour blood supply was observed. Panax ginseng preparations possess immunomodulatory properties and show potent antitumour activity.
In this study, maternal toxicity and developmental effects of exposure to Ascaris trypsin inhibitor were evaluated in mice. Pregnant BALB/c females were injected intraperitoneally by Ascaris inhibitor /AIT/ at 200, 300, and 400 mg/kg body weight/day, on days 12 to 15 of gestation (stage of fetal development). At day 19 of pregnancy, uterine contents were inspected for implantation sites, early resorptions (moles), living fetuses and dead fetuses. The living fetuses were weighed and examined for external, internal and skeletal abnormalities. The results showed that AIT induced maternal toxicity, evidenced by maternal deaths, abortions, bleeding from uterus and reduced body weight gain as compared to control (p <0.01). There were no differences between the control group and the rest of all groups investigated for total implantation sites and early resorptions. Fetotoxicity was observed as shown by the decrease in the number of living fetuses and mean fetal weight, a high rate of intrauterine fetal deaths, delayed skeletal ossification, occurrence of pathological changes of fetal organs and tissues. Only one type of congenital malformations (hydronephrosis) was noted in fetuses after injection of higher doses of AIT.
Recently the increasing prevalence of gastrointestinal diseases, including neoplasm, has resulted in the necessity of characterising not only the tumours, but also healthy mucosa. Research into the morphological changes of healthy mucosa under different experimental conditions, including drugs, special diets and the use of probiotic bacteria, is greatly facilitated by the availability of animal models. In spite of the widespread use of mice in gastrointestinal research, there is a lack of information on the qualitative and quantitative histological characteristics of the intestinal mucosa of the mouse. The aim of this study was to assess the morphological characteristics and the postnatal development of the small intestine of wild type mice — C57BL/6J. The mice were aged either 5 weeks or 12 weeks. The 12-week-old mice had been weaned at the age of 5 weeks. After dissection the small intestine was divided into 5 equal portions and randomly chosen microscopical sections from each were stained with haematoxylin and eosin. The parameters describing the morphology of the small intestine (villus height, depth of the crypt, villus width near the crypt, width of the villus connective tissue near the crypt, thickness of the muscular layer and the height of the enterocytes and their nuclei) were evaluated under a light microscope. In both age groups the height and width of the villi decreased, while the thickness of the muscular layer increased in the distal direction. The height of the enterocytes decreased and the height of the enterocyte nucleus increased towards the colon in both age groups. The depth of the crypts was greater in the younger animals than in the older ones. Our data provides the baseline morphological description of the small intestinal mucosa in wild type mice, strain C57BL/6J, which can be used as a reference for testing the influence of drugs, toxins, nutrients and inborn mutations on the mouse intestine.
Cross-resistance between Toxocara canis and Trichinella spiralis was studied in CBA/J mice exposed to varying doses of T. canis and 14 days later challenged with 400 larvae of T. spiralis. Intestinal burden of T. spiralis on day 7 post infection (PI) in mice given 25 ova of T. canis was 70% of challenge control burden, but in mice given 250 ova the burden was consistently below 20% of the control value. Male worms were preferentially expelled from mice exposed to T. canis. Recovery of muscle larvae was reduced in mice given 250 ova, but not in mice given 25 ova. Intestinal burdens of T. spiralis in T. canis-sensitized mice (250 ova) was 58% of the control values at 36 h PI, and most of the remaining worms were expelled between 5 and 7 days PI. Worms from mice given 250 ova released lower numbers of newborn larvae in vitro.
The present study has examined the level of total IgA and antigen-specific IgA antibodies in serum and bile in various inbred strains of mice infected with Trichinella spiralis. These strains of mice differ in the speed at which they expel the adult worms from the gut. BALB/c and CBA mice expel adult worms faster than C3H and C57BL/6 mice. However, the CBA strain of mice is more resistant to the establishment of an initial infection of T. spiralis than BALB/c mice. While total serum IgA and bile sIgA concentrations correlated with the time course of the expulsion of adult worms, there was no similar correlation between IgA concentrations and the intensity of T. spiralis infection during the muscle phases of infection in any of the strains of mice investigated. Specific IgA antibodies in sera and sIgA antibodies in bile were measured by ELISA in C57BL/6 mice using crude somatic L1 muscle larvae (AgL1) and crude adult worm (AgAd) antigens. A pronounced increase in sIgA antibodies to AgL1 antigen was found by day 9 of infection in bile. However, a gradual increase in IgA in serum to AgAd antigen was observed from 6 till 24 DAI. Specific IgA response in serum to AgAd was much higher than to AgL1 and, in contrast the sIgA response in bile, was more pronounced to AgL1 than to AgAd. This result suggests that bile may also provide a valuable source of sIgA.
The weight of the larval cyst mass (LCM), splenomegaly and the amount of splenic amyloid deposition, was shown to be dependant on a putative alveolar hydatid cyst (AHC) soluble component. The increase in LCM, spleen weight, and splenic amyloid was inversely proportional to the number of cyst washings during the preparation of the inoculum. A minimum of 8 washings were found necessary to induce significant reduction in parasite growth and amyloid deposition. With twenty four washings progressive phase of infection was aborted; while the restrictive phase was extended to 8 weeks. This finding was further confirmed by surgical transplantation of cysts obtained from infected mice at 12 weeks post infection to normal mice. The amount of splenic amyloid deposits, LCM and spleen weight after one week post-transplant was statistically not different from those in mice infected with AHC following 24 washings at 12 weeks post infection. The restrictive phase was eliminated following transplantation. AHC-extract (AHC-EXT) prepared from AHC before or after 24 washings was shown to retain its antigenicity and react with infected mice sera in the gel diffusion test. The reaction intensity and the number of bands seen were less after washing.
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