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Memory load effect in auditory-verbal short-term memory task: EEG fractal and spectral analysis
No full textThe objective of this preliminary study was to quantify changes in complexity of EEG using fractal dimension (FD) alongside linear methods of spectral power, event-related spectral perturbations, coherence, and source localization of EEG generators for theta (4-7 Hz), alpha (8-12 Hz), and beta (13-23 Hz) frequency bands due to a memory load effect in an auditory-verbal short-term memory (AVSTM) task for words. We examined 20 healthy individuals using the Sternberg's paradigm with increasing memory load (three, five, and seven words). The stimuli were four-letter words. Artifact-free 5-s EEG segments during retention period were analyzed. The most significant finding was the increase in FD with the increase in memory load in temporal regions T3 and T4, and in parietal region Pz, while decrease in FD with increase in memory load was registered in frontal midline region Fz. Results point to increase in frontal midline (Fz) theta spectral power, decrease in alpha spectral power in parietal region-Pz, and increase in beta spectral power in T3 and T4 region with increase in memory load. Decrease in theta coherence within right hemisphere due to memory load was obtained. Alpha coherence increased in posterior regions with anterior decrease. Beta coherence increased in fronto-temporal regions. Source localization delineated theta activity increase in frontal midline region, alpha decrease in superior parietal region, and beta increase in superior temporal gyrus with increase in memory load. In conclusion, FD as a nonlinear measure may serve as a sensitive index for quantifying dynamical changes in EEG signals during AVSTM tasks
Ovarian hormone level alterations during rat post-reproductive life-span influence CD8+T-cell homeostasis
Get PDFThe study examined the putative role of ovarian hormones in shaping of rat peripheral T-cell compartment during post-reproductive period. In 20-month-old rats ovariectomized (Ox) at the very end of reproductive period, thymic output, cellularity and composition of major TCR alpha beta+peripheral blood lymphocyte and splenocyte subsets were analyzed. Ovariectomy led to the enlargement of CD8 + peripheral blood lymphocyte and splenocyte subpopulations. This reflected: (i) a more efficient thymic generation of CD8 + cells as indicated by increased number of CD4+CD8+double positive and the most mature CD4CD8+TCR alpha beta(high) thymocytes and CD8 + recent thymic emigrants (RTEs) in peripheral blood, but not in the spleen of Ox rats, and (ii) the expansion of CD8 + memory/activated peripheral blood lymphocytes and splenocytes. The latter was consistent with a greater frequency of proliferating cells among freshly isolated memory/activated CD8 + peripheral blood lymphocytes and splenocytes and increased proliferative response of CD8 + splenocytes to stimulation with plate-bound anti-CD3 antibody. The former could be related to the rise in splenic IL-7 and IL-15 mRNA expression. Although ovariectomy affected the overall number of CD4 + T cells in none of the examined compartments, it increased CD4+FoxP3 + peripheral blood lymphocyte and splenocyte counts by enhancing their generation in periphery. Collectively, the results suggest that ovariectomy-induced long-lasting disturbances in ovarian hormone levels (mirrored in diminished progesterone serum level in 20-month-old rats) affects both thymic CD8 + cell generation and peripheral homeostasis and leads to the expansion of CD4+FoxP3 + cells in the periphery, thereby enhancing autoreactive cell control on account of immune system efficacy to combat infections and tumors
Autoantibody response and pregnancy-related pathology induced by combined LPS and tetanus toxoid hyperimmunization in BALB/c and C57BL/6 mice
No full textRecent data concerning antiphospholipid syndrome (APS) induction have shown that beta(2)-glycoprotein I (beta(2)GPI) binds lipopolysaccharide (LPS), which results in conformational changes, exposition of a cryptic epitope and possible pathological anti-beta(2)GPI antibody production. In order to investigate the effects of LPS on the induction of APS-related pathology, we performed hyperimmunization of BALB/c and C57BL/6 mice with LPS, alone or in combination with tetanus toxoid (TTd), a protein structurally similar to beta(2)GPI. We report that, although high affinity pathological anti-beta(2)GPI antibodies were produced in all groups of animals, the reproductive pathology was recorded only in mice that received both LPS and TTd, implying on the important roles of both infections and molecular mimicry in APS pathogenesis. Moreover, APS-related reproductive pathology was more pronounced in BALB/c (lowered fertility and fecundity) than C57BL/6 mice (lowered fecundity), which correlated well with the disruption in natural antibody network observed in BALB/c mouse strain
Developing a quality management tool for preparing Good Distribution Practice audit of pharmaceutical contract vaccine distributor
Get PDFOutsourcing is increasingly used by the vaccine manufacturers. When the manufacturing activities are outsourced, the contract manufacturer's Good Manufacturing Practice compliance needs to be confirmed through auditing. In the same way, when distribution is outsourced, the contract distributor's Good Distribution Practice compliance needs to be confirmed through auditing. The objective of this study was to develop an audit preparation tool for the pharmaceutical contract vaccine distributor and to validate its contents by using the Delphi method. Based on this, a tool was developed for the contract vaccine distributors. The Delphi method was used with a group of 14 experts from the pharmaceutical industry, authorities and university. The response rate in the Delphi questionnaire round was 100 %. The tool consisted of 33 quality items, out of which 29 (88%) achieved the pre-defined agreement rate level ( gt 75%). The four quality items which did not achieve the pre-defined agreement rate were excluded from the tool. The expert group suggested only minor changes to the tool. The results show that the content validity of the developed audit preparation tool was good. The resultant questionnaire is ready to use. Developed the ready-to-use questionnaire based on critical factors evaluation, gives an objective picture of the possibilities of the potential partner and help organisations make quality decision on the selection of contract vaccine distributors. The contract vaccine distributor must be permanently controlled and analysed, so as to maintain the required quality and to keep low level of costs
Fungicide sensitivity of Trichoderma spp. from Agaricus bisporus farms in Serbia
No full textTrichoderma species, the causal agents of green mould disease, induce great losses in Agaricus bisporus farms. Fungicides are widely used to control mushroom diseases although green mould control is encumbered with difficulties. The aims of this study were, therefore, to research in vitro toxicity of several commercial fungicides to Trichoderma isolates originating from Serbian and Bosnia-Herzegovina farms, and to evaluate the effects of pH and light on their growth. The majority of isolates demonstrated optimal growth at pH 5.0, and the rest at pH 6.0. A few isolates also grew well at pH 7. The weakest mycelial growth was noted at pH 8.0-9.0. Generally, light had an inhibitory effect on the growth of tested isolates. The isolates showed the highest susceptibility to chlorothalonil and carbendazim (ED50 less than 1mg L-1), and were less sensitive to iprodione (ED50 ranged 0.84-6.72mg L-1), weakly resistant to thiophanate-methyl (ED50 = 3.75-24.13mg L-1), and resistant to trifloxystrobin (ED50 = 10.25-178.23mg L-1). Considering the toxicity of fungicides to A. bisporus, carbendazim showed the best selective toxicity (0.02), iprodione and chlorothalonil moderate (0.16), and thiophanate-methyl the lowest (1.24), while trifloxystrobin toxicity to A. bisporus was not tested because of its inefficiency against Trichoderma isolates
Effects of orally applied Fes p1-displaying L. plantarum WCFS1 on Fes p1 induced allergy in mice
No full textGroup I grass pollen allergens are major contributors to grass pollen-related seasonal allergic rhinitis, and as such a primary target for allergen specific immunotherapy. In this study the potential therapeutic role of oral application of Lactobacillus plantarum WCFS1, directing cell wall attachment of the recombinant Fes p1 allergen, from Festuca pratensis was tested in a mouse model of Fes p1 allergy. For surface expression of Fes p1 allergen in L. plantarum WCFS1 pSIP system with inducible expression was used. Balb/c mice were sensitized with Fes p1 protein in alum and subsequently received live recombinant L. plantarum orally. Antibody levels (IgE, total IgG, IgG1, IgG2a, and IgA) were determined by ELISA. Differential eosinophil count in peripheral blood was performed. Reduced peripheral blood eosinophilia and increased serum IgG2A levels was detected in both groups which received live L. plantarum orally. Specific serum IgA levels were increased only in mice treated with the recombinant bacteria. Oral application of L. plantarum WCFS1 has a beneficial therapeutic effect in a mouse model of Fes p1 allergy. Cell surface expression of Fes p1 allergen potentiates this phenomenon in an allergen specific way. (C) 2015 Elsevier B.V. All rights reserved.Peer reviewed version: [https://intor.torlakinstitut.com/handle/123456789/652
Aging impairs endocytic capacity of splenic dendritic cells from dark agouti rats and alters their response to TLR4 stimulation
Get PDFThe study was undertaken considering: i) that relative proportion of distinct subsets of splenic dendritic cells (DCs) is strain-specific and predictive for the susceptibility to autoimmune diseases; ii) age-related changes in endocytic, allostimulatory and polarizing capacity of splenic OX62+ DCs from Albino Oxford rats (relatively resistant to Th1/Th17-mediated diseases) and iii) strain specificities in age-related changes of mouse DCs. To ascertain whether there are strain specificities in age-related rat DC changes, we examined the influence of aging on OX62+ DCs from Dark Agouti (DA) rats prone to Th1/Th17-mediated autoimmune diseases. The study provided additional evidence that the predominance of CD4-cells within OX62+ DCs from young adult rats correlates with their susceptibility to Th1/Th17-mediated diseases. Consistently, lipopolysaccharide (LPS)-matured DCs from 3-month-old (young) rats exhibited Th1 driving force when co-cultured with allogeneic CD4+ T cells. This most likely reflected enhanced TNF-alpha and iNOS expression. Comparing with young rats, OX62+ DCs from 26-month-old (aged) rats showed: i) diminished endocytic capacity; ii) impaired ability to mature in vitro upon LPS stimulation (as indicated by lower MHC II, CD86 and CD40 surface expression), which is consistent with the increase in their IL-10 production, and iii) diminished allostimulatory capacity and loss of Th1-driving capacity in the mixed lymphocyte reaction. The latter, probably, reflected greater IL-10 production by LPS-stimulated DC from aged rats, as well as lower CD40 density on their surface. Overall, our findings suggest that aging might affect DA rat capability to mount an efficient Th1 immune response, and consequently susceptibility to Th1/Th17-mediated pathology
AggLb Is the Largest Cell-Aggregation Factor from Lactobacillus paracasei Subsp paracasei BGNJ1-64, Functions in Collagen Adhesion, and Pathogen Exclusion In Vitro
Get PDFEleven Lactobacillus strains with strong aggregation abilities were selected from a laboratory collection. In two of the strains, genes associated with aggregation capability were plasmid located and found to strongly correlate with collagen binding. The gene encoding the auto-aggregation-promoting protein (AggLb) of Lactobacillus paracasei subsp. paracasei BGNJ1-64 was cloned using a novel, wide-range-host shuttle cloning vector, pAZILSJ. The clone pALb35, containing a 11377-bp DNA fragment, was selected from the SacI plasmid library for its ability to provide carriers with the aggregation phenotype. The complete fragment was sequenced and four potential ORFs were detected, including the aggLb gene and three surrounding transposase genes. AggLb is the largest known cell-surface protein in lactobacilli, consisting of 2998 aa (318,611 Da). AggLb belongs to the collagen-binding superfamily and its C-terminal region contains 20 successive repeats that are identical even at the nucleotide level. Deletion of aggLb causes a loss of the capacity to form cell aggregates, whereas overexpression increases cellular aggregation, hydrophobicity and collagen-binding potential. PCR screening performed with three sets of primers based on the aggLb gene of BGNJ1-64 enabled detection of the same type of aggLb gene in five of eleven selected aggregation-positive Lactobacillus strains. Heterologous expression of aggLb confirmed the crucial role of the AggLb protein in cell aggregation and specific collagen binding, indicating that AggLb has a useful probiotic function in effective colonization of host tissue and prevention of pathogen colonization
Evaluation of autochthonous lactic acid bacteria as starter cultures for production of white pickled and fresh soft cheeses
Get PDFIn order to preserve the traditional manufacturing of white pickled (WPC) and fresh soft cheeses (FSC), well-characterized autochthonous lactic acid bacteria (LAB) with advantageous characteristics were applied for the production of the cheeses at small industrial scale under the controlled conditions. Selected LAB for design of defined mixed starter cultures belonged to Lactococcus lactis ZGBP5-9, Enterococcus faecium ZGPR1-54 and Lactobacillus plantarum ZGPR2-25 for FSC production and to Lc. lactis BGAL1-4, Lactobacillus brevis BGGO7-28 and Lb. plantarum BGGO7-29 for WPC production. A sensory evaluation indicated that the cheeses obtained by inoculation with selected autochthonous LAB are similar to the traditional cheese and received the best scores. Viable cell counts of LAB used for the production of both type chesses was high, over 10(6) cfu g(-1). High viability of the surveyed strains was supported with PCR-DGGE, which confirm the retention of selected LAB strains as starter cultures in cheese production. Next, PFGE analysis showed that each single strains, selected in particular cheese mixed culture, revealed unique SmaI PFGE pattern that could enable efficient discrimination and monitoring of the strains in industrial process. As some of the selected LAB strains are attributed as potential probiotics, produced cheeses could be considered as functional food
Aging affects rat inflammatory peritoneal exudate composition and macrophage inflammatory mediator production in a strain-dependent manner
Get PDFThe present study was designed to examine influence of aging on
macrophage proinflammatory/anti-inflammatory capacity in rat model of
thioglycollate-induced peritonitis. Peritoneal macrophages were isolated
from young (3-months-old) and aged (18-months-old) Dark Agouti (DA)
and Albino Oxford (AO) rats seven days post-injection of thioglycollate
medium. Freshly isolated peritoneal exudate cells were examined for the
expression of CD163, CCR7, CD14 and TLR4, whereas cytokine
production (TNF-α, IL-6 and IL-10) and arginine metabolism end-products
(NO and urea) were assayed in vitro under basal conditions and following
stimulation with LPS. In DA rat inflammatory peritoneal exudate, aging
diminished the frequency of cells with a “resolving macrophage”
CD14+CD163+ phenotype. However, in AO rats, which exhibited stable
frequency of CD14+CD163+ cells in inflammatory peritoneal exudate with
aging, the proportion of CCR7-bearing peritoneal cells, presumably
immigrating inflammatory monocytes, was diminished in aged animals.
Under basal culture conditions, macrophages from aged rats of both strains
released less amount of TNF-α, IL-6 and IL-10, but produced more urea
than cells from young strain-matched rats. However, these changes were
more pronounced in peritoneal macrophages from AO rats. Additionally,
age-related decrease in the frequency of TLR4-expressing cells was
observed among fresh peritoneal exudate cells from AO rats. Upon LPS
stimulation, the production of prototypic inflammatory cytokines (TNF-α
and IL-6) was diminished in macrophages from aged AO rats, whereas
aging had the opposite effect on their production in DA rat macrophages.
Moreover, aging increased NO production in LPS-stimulated macrophages
from DA rats, whereas urea production was enhanced in macrophages from
both strains, but this increase was strikingly more pronounced in
macrophages from AO rats. Collectively, results suggest that aging affects
inflammatory peritoneal exudate cellular composition and macrophage
proinflamatory/immunomodulatory capacity in a strain- specific manne