Моделирование изменения цен финансовых активов

В работе представлена модель процесса изменения цен финансовых активов на рынке. Описан путь построения модели, ее экономическая интерпретация, найдены моменты процесса и исследовано его поведение в предельном случае. Для сравнения с данной моделью приведены примеры некоторых других существующих моделей.У рoботi представлена модель процесу змiни цiн фiнансових активiв на ринку. Описано шлях побудови моделi, її економiчна iнтерпретацiя, знайдено моменти процесу, дослiджено його поведiнку у граничному випадку. Для порiвняння з даною моделлю наведено приклади деяких iнших моделей, що iснують.A model of process for financial assets — prices changing on market is presented. The way of the model’s construction is described, its economic interpretation, a moments of the process are obtained, its behavior in limit case is investigated. For comparison with the given model examples of other models are presented

Immunization of young heifers with staphylococcal immune evasion proteins before natural exposure to Staphylococcus aureus induces a humoral immune response in serum and milk

Background: Staphylococcus aureus, a leading cause of mastitis in dairy cattle, causes severe mastitis and/or chronic persistent infections with detrimental effects on the cows' wellbeing, lifespan and milk production. Despite years of research there is no effective vaccine against S. aureus mastitis. Boosting of non-protective pre-existing immunity to S. aureus, induced by natural exposure to S. aureus, by vaccination may interfere with vaccine efficacy. The aim was to assess whether experimental immunization of S. aureus naïve animals results in an immune response that differs from immunity following natural exposure to S. aureus. Results: First, to define the period during which calves are immunologically naïve for S. aureus, Efb, LukM, and whole-cell S. aureus specific serum antibodies were measured in a cohort of newborn calves by ELISA. Rising S. aureus specific antibodies indicated that from week 12 onward calves mounted an immune response to S. aureus due to natural exposure. Next, an experimental immunization trial was set up using 8-week-old heifer calves (n = 16), half of which were immunized with the immune evasion molecules Efb and LukM. Immunization was repeated after one year and before parturition and humoral and cellular immunity specific for Efb and LukM was determined throughout the study. Post-partum, antibody levels against LukM and EfB were significantly higher in serum, colostrum and milk in the experimentally immunized animals compared to animals naturally exposed to S. aureus. LukM specific IL17a responses were also significantly higher in the immunized cows post-partum. Conclusions: Experimental immunization with staphylococcal immune evasion molecules starting before natural exposure resulted in significantly higher antibody levels against Efb and LukM around parturition in serum as well as the site of infection, i.e. in colostrum and milk, compared to natural exposure to S. aureus. This study showed that it is practically feasible to vaccinate S. aureus naïve cattle and that experimental immunization induced a humoral immune response that differed from that after natural exposure only.</p

Intramammary immunity against Staphylococcus aureus in cattle

Mastitis in cattle is a worldwide problem in dairy farming with a major impact on animal welfare, life span and milk production. Interestingly, quarters of the same cow can differ in their susceptibility to mastitis. This indicates that susceptibility is defined on the quarter level rather than the cow level. To investigate whether milk characteristics play a role in quarter susceptibility to mastitis, we collected quarter milk samples of morning and evening milk, analysed the milk composition, and determined in vitro growth of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), two major mastitis causing pathogens, in these fresh milk samples. We found that almost all measured milk components differed significantly between quarters and that they showed a diurnal pattern. Furthermore, we observed that quantitative growth of S. aureus and E. coli differs significantly between morning milk and evening milk. Mixed model analyses revealed that replication of S. aureus was negatively associated with fat concentrations, S. aureus specific IgG1 antibodies, and morning milk. Replication of E. coli was negatively associated with fat concentrations, and positively associated with morning milk. Next, we studied whether the milk composition also influenced in vivo growth of S. aureus. Our results revealed that the numbers of S. aureus reisolated from milk post experimental intramammary inoculation was positively associated with the milk fat percentage and negatively associated with the S. aureus specific IgG1 titer pre-inoculation. Although the exact mechanism leading to the negative association between the S. aureus specific IgG1 titer and decreased S. aureus replication, both in vitro and in vivo, could not be identified, these finding supports the ongoing effort to develop a prophylactic vaccine against bovine S. aureus-induced mastitis and indicates that stimulation of the humoral immune response in milk against this bacterium might contribute to protection. Driven by this observation, we explored immunization strategies to increase the presence of antibodies in the bovine mammary gland. First, we determined the impact of vaccine administration via different routes and showed that vaccination via the subcutaneous route results in higher levels of specific, neutralizing antibodies compared to vaccination via the intramuscular, intranasal, and intramammary route. Next, we showed that subcutaneous immunizations resulted in higher antibody titers when administered near the udder compared to administration in the neck. Furthermore, we found that an Alum-Saponin-Oil based adjuvant stimulates the induction of specific antibody titers, favouring both IgG1 and IgG2 responses, and neutralization titers in both milk and serum more efficiently compared to adjuvants comprising Alum-Saponin or Alum-Oil. Moreover, while prime immunizations with Alum-Saponin-Oil near the udder resulted in high titer increases, immunization in the neck required a prime-boost regimen to induce similar titers. This implies that, when subcutaneously administered near the udder, a one-shot vaccination strategy with Alum-Saponin-Oil may be sufficient to efficiently increase intramammary antibody responses. Increased levels of functional antibodies allow the investigation of the role of antibodies in bovine intramammary immunity during S. aureus infections

Intramammary immunity against Staphylococcus aureus in cattle

Mastitis in cattle is a worldwide problem in dairy farming with a major impact on animal welfare, life span and milk production. Interestingly, quarters of the same cow can differ in their susceptibility to mastitis. This indicates that susceptibility is defined on the quarter level rather than the cow level. To investigate whether milk characteristics play a role in quarter susceptibility to mastitis, we collected quarter milk samples of morning and evening milk, analysed the milk composition, and determined in vitro growth of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), two major mastitis causing pathogens, in these fresh milk samples. We found that almost all measured milk components differed significantly between quarters and that they showed a diurnal pattern. Furthermore, we observed that quantitative growth of S. aureus and E. coli differs significantly between morning milk and evening milk. Mixed model analyses revealed that replication of S. aureus was negatively associated with fat concentrations, S. aureus specific IgG1 antibodies, and morning milk. Replication of E. coli was negatively associated with fat concentrations, and positively associated with morning milk. Next, we studied whether the milk composition also influenced in vivo growth of S. aureus. Our results revealed that the numbers of S. aureus reisolated from milk post experimental intramammary inoculation was positively associated with the milk fat percentage and negatively associated with the S. aureus specific IgG1 titer pre-inoculation. Although the exact mechanism leading to the negative association between the S. aureus specific IgG1 titer and decreased S. aureus replication, both in vitro and in vivo, could not be identified, these finding supports the ongoing effort to develop a prophylactic vaccine against bovine S. aureus-induced mastitis and indicates that stimulation of the humoral immune response in milk against this bacterium might contribute to protection. Driven by this observation, we explored immunization strategies to increase the presence of antibodies in the bovine mammary gland. First, we determined the impact of vaccine administration via different routes and showed that vaccination via the subcutaneous route results in higher levels of specific, neutralizing antibodies compared to vaccination via the intramuscular, intranasal, and intramammary route. Next, we showed that subcutaneous immunizations resulted in higher antibody titers when administered near the udder compared to administration in the neck. Furthermore, we found that an Alum-Saponin-Oil based adjuvant stimulates the induction of specific antibody titers, favouring both IgG1 and IgG2 responses, and neutralization titers in both milk and serum more efficiently compared to adjuvants comprising Alum-Saponin or Alum-Oil. Moreover, while prime immunizations with Alum-Saponin-Oil near the udder resulted in high titer increases, immunization in the neck required a prime-boost regimen to induce similar titers. This implies that, when subcutaneously administered near the udder, a one-shot vaccination strategy with Alum-Saponin-Oil may be sufficient to efficiently increase intramammary antibody responses. Increased levels of functional antibodies allow the investigation of the role of antibodies in bovine intramammary immunity during S. aureus infections

Differential Effects on Survival, Humoral Immune Responses and Brain Lesions in Inbred BALB/C, CBA/CA, and C57BL/6 Mice Experimentally Infected with Neospora caninum Tachyzoites

C57BL/6, BALB/c, and CBA/Ca mouse strains with different MHC-I haplotypes were compared with respect to susceptibility to Neospora caninum infection. Groups of 5 mice received , , or tachyzoites of the NC-Liverpool isolate by intraperitoneal injection and were observed for disease symptoms. Humoral responses, splenocyte interferon-γ (IFN-γ) production, cerebral parasite loads, and histopathology were evaluated at human end points or the latest at 34 days postinfection (PI). The mortality rates in C57BL/6 mice were the highest, and relatively high levels of IgG1 antibodies were detected in those mice surviving till 34 days PI. In lymphocyte proliferation assays, spleen cells from C57BL6 mice stimulated with N. caninum antigen extract exhibited large variations in IFN-γ production. In BALB/c mice mortality was 0% at the lowest and 100% at the highest infection dose. Serologically they responded with high levels of both IgG2a and IgG1 subclasses, and lymphocyte proliferation assays of surviving mice yielded lower IFN-γ levels. CBA/Ca mice were the most resistant, with no animal succumbing to infection at a dose of and tachyzoites, but 100% mortality at tachyzoites. High IgG2a levels as well as increased IFN-γ in lymphocyte proliferation assays were measured in CBA/Ca mice infected with tachyzoites

The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

Intramammary infections in cattle resulting in mastitis have detrimental effects on cows' well-being, lifespan and milk production. In the host defense against S. aureus mastitis antibodies are thought to play an important role. To explore potential ways to increase antibody titers in the bovine mammary gland the effects of various adjuvants on the magnitude, isotype, and neutralizing capacity of antibodies produced following subcutaneous vaccine administration at different immunization sites were analyzed. In this study, α-toxoid was used as a model antigen and formulated in three different alum-based adjuvants: Alum-Saponin, Alum-Oil, and Alum-Saponin-Oil. Vaccines were administered near the suspensory ligament of the udder or in the lateral triangular area of the neck. At both immunization sites, immunization with α-toxoid in Alum-Saponin-Oil resulted in higher specific antibody titers in milk and serum as compared with Alum-Oil and Alum-Saponin, without favoring an IgG1, IgG2, or IgA response. Furthermore, the neutralizing capacity of milk serum and serum following immunization near the udder and in the neck was higher when Alum-Saponin-Oil was used as adjuvant compared with Alum-Oil and Alum-Saponin. Prime immunizations near the udder effectively increased both antibody isotype titers and neutralization titers, while prime plus boost immunizations were required to induce similar effects following immunization in the neck. Results indicate that subcutaneous administration of an Alum-Saponin-Oil based vaccine near the udder could be further explored for the development of a one-shot vaccination strategy to efficiently increase intramammary antibody responses

MOESM1 of The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

Additional file 1. Local reaction scores post-immunization. Local reaction scores (A) near the udder and (B) in the neck following prime (day 0) and boost (day 42) immunizations are depicted. Fig A shows the sum of the local reaction scores observed at the immunization site on the left and right side of the udder. Fig B shows the local reaction scores observed on the left side of the neck post-prime immunization and on the right side of the neck post-boost immunization. Data is expressed as the mean ± range per group for Alum–Saponin (filled circle), Alum–Oil (filled triangle), and Alum–Saponin–Oil (filled diamond)

MOESM2 of The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

Additional file 2. α-Toxin specific antibody isotype titers and neutralization titers in serum. Specific antibody isotype titers were measured in an α-toxin specific ELISA. The neutralization capacity of serum was analyzed in an α-toxin neutralization assay. Serum (A) IgG1 and (B) IgG2 antibody titers and (C) serum neutralization titers pre-immunization (filled circle), post-prime (filled triangle), and post-boost (filled diamond) immunization are expressed as the mean ± SEM per group. Significant mean titer differences are given in Table 1 and Additional file 3

The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

Intramammary infections in cattle resulting in mastitis have detrimental effects on cows' well-being, lifespan and milk production. In the host defense against S. aureus mastitis antibodies are thought to play an important role. To explore potential ways to increase antibody titers in the bovine mammary gland the effects of various adjuvants on the magnitude, isotype, and neutralizing capacity of antibodies produced following subcutaneous vaccine administration at different immunization sites were analyzed. In this study, α-toxoid was used as a model antigen and formulated in three different alum-based adjuvants: Alum-Saponin, Alum-Oil, and Alum-Saponin-Oil. Vaccines were administered near the suspensory ligament of the udder or in the lateral triangular area of the neck. At both immunization sites, immunization with α-toxoid in Alum-Saponin-Oil resulted in higher specific antibody titers in milk and serum as compared with Alum-Oil and Alum-Saponin, without favoring an IgG1, IgG2, or IgA response. Furthermore, the neutralizing capacity of milk serum and serum following immunization near the udder and in the neck was higher when Alum-Saponin-Oil was used as adjuvant compared with Alum-Oil and Alum-Saponin. Prime immunizations near the udder effectively increased both antibody isotype titers and neutralization titers, while prime plus boost immunizations were required to induce similar effects following immunization in the neck. Results indicate that subcutaneous administration of an Alum-Saponin-Oil based vaccine near the udder could be further explored for the development of a one-shot vaccination strategy to efficiently increase intramammary antibody responses

The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

Intramammary infections in cattle resulting in mastitis have detrimental effects on cows' well-being, lifespan and milk production. In the host defense against S. aureus mastitis antibodies are thought to play an important role. To explore potential ways to increase antibody titers in the bovine mammary gland the effects of various adjuvants on the magnitude, isotype, and neutralizing capacity of antibodies produced following subcutaneous vaccine administration at different immunization sites were analyzed. In this study, α-toxoid was used as a model antigen and formulated in three different alum-based adjuvants: Alum-Saponin, Alum-Oil, and Alum-Saponin-Oil. Vaccines were administered near the suspensory ligament of the udder or in the lateral triangular area of the neck. At both immunization sites, immunization with α-toxoid in Alum-Saponin-Oil resulted in higher specific antibody titers in milk and serum as compared with Alum-Oil and Alum-Saponin, without favoring an IgG1, IgG2, or IgA response. Furthermore, the neutralizing capacity of milk serum and serum following immunization near the udder and in the neck was higher when Alum-Saponin-Oil was used as adjuvant compared with Alum-Oil and Alum-Saponin. Prime immunizations near the udder effectively increased both antibody isotype titers and neutralization titers, while prime plus boost immunizations were required to induce similar effects following immunization in the neck. Results indicate that subcutaneous administration of an Alum-Saponin-Oil based vaccine near the udder could be further explored for the development of a one-shot vaccination strategy to efficiently increase intramammary antibody responses