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The study aimed at determining the effect of a multiple dose of lysozyme dimer (Lydium-KLP Nika Health Products) on primary humoral response in SRBC - immunized mice. The effects of a single (20 µg/kg) lysozyme dimer administered 2 h prior to antigen injection were compared with those of lysozyme dimer multiple doses (two-four) administered at one week intervals. The results of the study show that lysozyme dimer, irrespective of the number and range of the doses (2, 20 or 200 µg/kg) enhances humoral response to the antigen. The adjuvant action of lysozyme dimer is expressed in the increasing number of splenocytes producing hemolytic antibodies (PFC) and the total and 2-mercaptoethanol resistant level of anti-SRBC hemagglutinins. The strongest activation of the immune response was observed after a single administration and multiple injections at doses of 2 or 20 µg/kg. Three doses of lysozyme dimer (200 µg/kg each) injected at 7-day intervals decreased the number of PFC induced by this drug administered in a single dose of 20 µg/kg 2 h prior to immunization, but maintaining the potentializing impact on anti-SRBC antibody production. The results obtained in the study indicate that multiple doses of lysozyme dimer administered in doses recommended in veterinary practice (2-20 µg/kg), at 7-day intervals do not results in immunological tolerance.
W Polsce i na świecie próchnica została uznana za chorobę społeczną. Badania z udziałem ludzi potwierdziły, że za inicjację i postępowanie tej choroby odpowiedzialne są bakterie Streptococcus mutans. Wiele analiz wskazuje na kluczową rolę specyficznych białek S. mutans (antygen 1/11, glukozylotrasferaza GTF, białka GBP) w patogenezie próchnicy. Badania dowiodły, że antygeny te bądź ich fragmenty mogą być efektywnymi immunogenami przeciwko próchnicy.
Six thoroughbred horses formed a study group which was immunized twice with a vaccine (Equigrip, Rhone-Merieux), the control group was six unvaccinated horses. Blood was collected for hematological examinations, cellular immune responses, specific humoral immunity (HI) at days 0, 17, 34, 83, 117 and 123 of the experiment. On day 117 of the experiment, 3 horses of the experimental group and 3 horses of the control group were infected intranasally with a mixture of 2 subtypes (A-l and A-2) of the influenza virus. It is worth noting that 17 days after the first vaccination the lymphocyte stimulation index increased in all horses in the experimental group, while in four of the six unvaccinated horses (control) the index decreased. During this time a statistically significant increase of the specific antibodies titres was not found in vaccinated horses. Six days after the infection, the fairly high level of specific humoral immunity was accompanied by a strong stimulation of cellular immunity, which was expressed as a statistically significant increase in the lymphocyte stimulation index (as determined by the specific blastic transformation test) and was higher in vaccinated horses. Reisolation of the virus, which was attempted five days after the challenge from the nasal cavities of vaccinated horses was unsuccessful, while influenza virus subtype 2 was isolated from each of the vaccinated horses.
The viral etiology of the disease was established on the basis of virological, anatomopathological, and bacteriological examinations. The isolated aetiological agent of the European Brown Hare Syndrome virus (EBHS; Calicivirdae, Logovirus) was used to produce its own vaccine against EBHS. The vaccine was used to immune 82 hares and eliminated the mortality rate of EBHS infected hares under controlled conditions. The study confirmed the minor pathogenicity of the EBHS virus for rabbits and indicated the presence of cross-immune reactions between the EBHS and RHD viruses.
Y. enterocolitica infection of pigs is concerned with a common carrier and shedding states in this species. The aim of the study was to determine the influence of the experimental immunization of pigs with a selected Y. enterocolitica strains suspension on the controled infection course, the antibody level formation, as well as the duration of pathogen shedding. The immunization of pigs was enforced with a suspension of Y. enterocolitica strains previously inactivated with formol, suspended in PBS and demonstrated in vitro high immunogenicity in Respiratory Burst Activity/Potential Killing Activity (RBA/PKA) and Mitogen Transformation Test (MTT). The study was performed on 15 pigs divided into 3 groups. The animals from groups I and II received an immunizate with a density of 2.7 × 10⁹ cfu/ml administered subcutaneously in doses 2 ml and 5 ml, respectively, twice in a 2-week interval. The third group (control) was administered PBS in an analogous scheme. The evaluation in vivo was conducted after a per os challenge with a pathogenic strain of Y. enterocolitica O:3. The first and booster immunization had no effect on the clinical picture and body weight gains of the immunized animals. The fastest and strongest immune response to the per os challenge with Y. enterocolitica O:3 was observed in the control group, already in the first week post infection (wpi). Higher antibody levels were found in the group of animals where 5 ml 2.7 × 10⁹ cfu/cm³ subcutaneously were administered. In the first wpi bacterial shedding was observed in all animals that belonged to group I and the control group which persisted up to 3 wpi. Among the pigs from group II the shedding was observed in 3 out of 5 animals, and which finished in 6 days post infection. Applied experimental immunization against per os challenge with a pathogenic strain of Y. enterocolitica O:3 did not prevent pathogen shedding, but merely limited its intensity and duration.
The introduction of genetic or "naked DNA" vaccines may open a new era in vaccinology. DNA vaccination is a relatively simple process: a recombinant vector containing cDNA of the potentially protective pathogen antigen, is delivered to a host organism under the control of a strong promoter. It has been demonstrated that the introduced DNA remains stable as an episome for a long time and does not integrate into a genome of vaccinated organism. The type of immune response elicited by DNA vaccination depends very much on the antigen used and on the way of the vaccine delivery. Generally, DNA vaccination induces Tol-dependent rather than Th2-dependent immune response. DNA vaccines present many advantages over "traditional" ones. Firstly, it is easier to obtain a considerable amount of DNA than similar quantities of purified protective antigen protein. Secondly, the antigenic proteins synthesised within the host cell possess an appropriate molecular structure and undergo a posttranslational modifications specific for the native protein. The posttranslational modifications, for example glycosylation, cannot be introduced during expression of the recombinant protein antigens in bacterial hosts.
The aim of the research was to monitor the influence of neonatal thymectomy on the reactivity of chicken spleen structures. The investigations were carried out on chickens with the thymus removed on the 1st day after hatching and with antigen administered in the form of sheep erythrocytes (SRBC) at the age of 12 weeks. On days 6, 14 and 21 after antigen administration the spleen was taken out and histological slides were prepared. On the established area of HE slides germinal centres were counted and mature centres of type I and immature ones of type II were distinguished. Reaction to the acid phosphatase (APh) was done by the Gomori method. The results of the reaction was read on the established area within the periarterial lymphatic tissue (PAL) using the Thomson point method. It was found that neonatal thymectomy leads to a decrease in the number of germinal centres and simultaneously to the reduction of the intensity of APh reaction within the spleen PAL. Following immunization of the thymectomized chickens, in comparison to the control (group) a change of kinetics of germinal centers formation was discovered, mainly of type I. It was ascertained that in the succeeding days after the antigen administration the intensity of APh reaction within PAL was directly proportional to the number of immature germinal centres of type II. The results demonstrated a distinct association between the bursodependent and thymodependent spleen structures reactivity and confirmed the importance of the functional state of the thymus.
The aim of the study was to show the dynamics of lymphocytes T (receptor CD5+ ), Th (receptor CD4+), Tc/Ts (receptor CD8+), B (receptor IgM . mu chain), as well as lymphocytes with receptor CD25+ in rabbits immunised with Chlamydophila abortus and Chlamydophila psittaci. Moreover, a serological test was carried out. The analysis of the results indicated that the immunisation of rabbits with the studied antigens in case of lymphocytes T and their subpopulations caused a similar increase and decrease of their amount and in case of lymphocytes B only an increase. Those changes are noted in 7th . 14th day after the immunisation and they persist until 42nd . 56th day of the experiment. Moreover, the positive titre of antibodies was noticed on the 35th . 42nd day after the immunisation, i.e. 4-6 weeks after the changes in the amount of lymphocytes.
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