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Effects of l.rhamnosus la68 on the immune system of c57 bl/6 mice upon oral administration
Uvod: Probiotici se koriste vekovima kao deo humane ishrane i u poslednje vreme pridaje im se sve vise značaja. Cilj ovog rada bio je ispitivanje imunoloških aspekata konzumiranja soja Lactobacillus rhamnosus LA68.
Metodologija: Soj LA68 davan je miševima oralno, gavažom četiri puta nedeljno tokom
mesec dana. Korišćena je sveža prekonoćna kultura i jedna doza sastojala se od 2x109
CFU. Nakon isteka eksperimentalnog perioda izolovani su mišji splenociti i analizirani
pomoću protocne citometrije. Meren je i odgovor splenocita u vidu sekrecije citokina
(IFN-y, IL-6, IL-10 and IL-17) kao i proliferacija nakon stimulacije lipopolisaharidom i peptidoglikanom. Analizirani su i citokini u serumu eksperimentalnih miševa. Zdravstveno
stanje životinja praćeno je merenjem težine i osnovnih biohemijskih parametara.
Rezultati: Oralna aplikacija soja LA68 dovodi do značajnog smanjenja zastupljenosti
CD3+, CD25+ i CD19+ celija i do povecanja CD11b+ and CD16/CD32+ ćelija u slezini
eksperimentalnih miševa. Detektovana je i povećana osetljivost na stimulaciju merenjem ćelijske proliferacije i sekrecije IL-6. U serumu eksperimentalnih miševa detektovan
je poviseni nivo IFN-y i smanjenje IL-10. Težina životinja i biohemijski parametri nisu se
razlikovali među grupama i ulazili su u opseg normalnih vrednosti za ovu vrstu miša.
Zaključak: Dobijeni rezultati ukazuju na povećanu osetljivost splenocita na stimulaciju,
aktivaciju Th1 tipa imunskog odgovora i pomeranje leukocitne populacije ka monocitno/granulocitnoj populaciji. Detektovane promene mogu pomoći organizmu u odbrani
protiv određenih vrsta infekcija i umanjiti simtome alergije.Introduction: Probiotic bacteria have been used in human nutrition for centuries and
are attracting more attention in recent years. The aim of this study was to evaluate the
effects of Lactobacillus rhamnosus LA68 on the immune system of mice.
Methodology: In order to examine the immunological aspects of probiotic consumption LA68 was orally administrated via gavage to C57 BL/6 mice. Gavage was performed
four times per week for the duration of one month. Fresh overnight culture was used
and one dose consisted of 2x109 CFU. Upon completion mouse splenocytes were isolated and analyzed by flow cytometry. The magnitude of splenocyte proliferation upon
stimulation with LPS and peptidoglycan and cytokine levels (IFN-y, IL-6, IL-10 and IL-17)
were assessed. Cytokine levels in the serum were also analyzed. Mouse well being was
monitored with weight measurement and basic blood biochemisty.
Results: Oral application of strain LA68 leads to a significant decrease of CD3+, CD25+
and CD19+ cells, and an increase of CD11b+ and CD16/CD32+ positive cell populations
in the mouse spleen. Increased sensitivity to stimulation through proliferation and IL-6
secretion was detected. Increased serum IFN-y and decreased IL-10 levels were found.
Animal weight and biochemical parameters did not differ between the groups and were
within the normal values for this mouse strain.
Conclusion: Our results show increased responsiveness of splenocytes, activation of
the Th1 type of immune response, and a shift of leukocyte populations toward monocyte/granulocyte populations. Changes detected consist of a boost in defense mechanisms against certain types of bacteria and ameliorate allergy symptoms
Use of Lactobacillus helveticus BGRA43 for Manufacturing Fermented Milk Products
Lactobacillus helveticus BGRA43 isolated from human intestines shows antimicrobial activity against foodborne pathogens and during fermentation in milk releases peptides with demonstrated anti-inflammatory properties. In this study, it was found that strain BGRA43 exhibits antimicrobial activity against human pathogens Yersinia enterocolitica, Shigella sonnei, S. flexneri and Streptococcus pneumoniae. Strain BGRA43 was able to survive in simulated gastric juice containing milk and retained cell number stability during the incubation in simulated intestinal conditions. In addition, LC/MS/MS analysis showed the ability of BGRA43 to hydrolyze beta-lactoglobulin. Abundant growth of strain BGRA43 occurred in the presence of prebiotics inulin or concentrated oat bran beta-glucan (Nutrim (R)), even when used as the sole carbon. source. Similarly, strain BGRA43 grew satisfactorily in pure cow's or goat's milk as well as in the milk containing inulin or Nutrim (R). Using the probiotic strain BGRA43 as a single starter strain, fermented milk products obtained from cow's or goat's milk with or without inulin or Nutrim (R) contained about 10(7) CFU/mL. The products were homogeneous and viscous and the best sensory scores were observed for fermented milk beverage made from reconstituted skimmed milk, whole cow's milk and whole goat's milk supplemented with 1 % inulin
In Vitro Antibacterial Activity of Cysteine Protease Inhibitor from Kiwifruit (Actinidia deliciosa)
The need for replacing traditional pesticides with alternative agents for the management of agricultural pathogens is rising worldwide. In this study, a cysteine proteinase inhibitor (CPI), 11 kDa in size, was purified from green kiwifruit to homogeneity. We examined the growth inhibition of three plant pathogenic Gram-negative bacterial strains by kiwi CPI and attempted to elucidate the potential mechanism of the growth inhibition. CPI influenced the growth of phytopathogenic bacteria Agrobacterium tumefaciens (76.2 % growth inhibition using 15 mu M CPI), Burkholderia cepacia (75.6 % growth inhibition) and, to a lesser extent, Erwinia carotovora (44.4 % growth inhibition) by inhibiting proteinases that are excreted by these bacteria. Identification and characterization of natural plant defense molecules is the first step toward creation of improved methods for pest control based on naturally occurring molecules
Approach to the Integration of Management Systems in a Pharmaceutical Organization
This paper discusses how a system approach to management can be used for the development and implementation of an integrated management system (IMS) in a company producing medicinal products. It is argued in the paper that approaches to the solutions of how to integrate management systems all require two elements: a conceptual model and a supporting methodology. Although a large number of models has been developed that could provide the basis for integration, development of methodologies to achieve fully integrated systems is still stagnating. This paper presents the IMS model that can be used to integrate the requirements of existing and upcoming standards in the pharmaceutical industry, followed by a discussion on the issue of the IMS methodology
Genotypic diversity and virulent factors of Staphylococcus epidermidis isolated from human breast milk
Staphylococcus epidermidis strains were isolated from the expressed human breast milk (EHM) of 14 healthy donor mothers. Genetic diversity was evaluated using RAPD-PCR REP-PCR and pulse-field gel electrophoresis (PFGE). PFGE allowed the best discrimination of the isolates, since it provided for the greatest diversity of the analyzed genomes. Among the S. epidermidis strains, resistance to gentamicin, tetracycline, erythromycin, clindamycin or vancomycin was detected, whilst four isolates were multiresistant. The results from our study demonstrate that staphylococci from EHM could be reservoirs of resistance genes, since we showed that tetK could be transferred from EHM staphylococci to Gram-negative Escherichia coli. Most of the staphylococcal strains displayed excellent proteolytic and lipolytic activities. Additionally, the presence of ica genes, which was related to their ability to form a biofilm on tissue culture plates, and the presence of virulence factors including autolysin/adhesin AtLE, point to their pathogenic potential
Measles situation in Serbia in an era of measles elimination (2007-2009)
Following the introduction of measles immunization in Serbia in 1971, measles outbreaks were recorded every 3 to 5 years until 1997. The outbreak in 1997 with 4000 cases was the last large outbreak in Serbia. In 2007, an outbreak with 191 laboratory confirmed or epidemiologically linked cases was reported in Vojvodina. In 2008 and 2009, only 3 cases were confirmed. From 2007-2009, measles infections were most frequently detected in the Roma population but also in non-immunized or partially immunized persons from the general population
Strain differences in the humoral immune response to commensal bacterial antigens in rats
We have investigated the immune response to commensal bacterial species in the two inbred rat strains: Dark Agouti (DA) and Albino Oxford (AO). The predominant Gram-negative aerobe in our rats' intestinal bacterial flora was Escherichia coli, while Proteus mirabilis was isolated only from DA rat strain. We report that sera from both DA and AO rat strains contain specific IgG against predominant intestinal flora. Intramuscular administration of commensal bacterial antigens provoked only Th1-type antibody response in AO rats while DA rats developed mixed Th1- and Th2-type antibody response to E. coli and Th1-type response to P. mirabilis antigens. Weaker antibody production to own E. coli and higher serum levels of natural IgG and IgA P. mirabilis-specific antibodies combined with higher CD3+ cells proliferation was found in AO rats. Strain difference in the pattern of antibody production and differential regulation of immune response to commensal bacteria may contribute to the marked differences in the immune reactivity of AO and DA rats
Role of molecular mimicry and polyclonal cell activation in the induction of pathogenic beta 2-glycoprotein I-directed immune response in Balb/c mice upon hyperimmunization with tetanus toxoid
It is known that tetanus toxoid (TTd)-hyperimmunization induces increased titer of sera beta 2-glycoprotein I (beta 2GPI)-specific antibodies (Abs) in Balb/c mice. The concentrations of such induced anti-beta 2GPI Abs as well as their pathogenic potential are strongly influenced by the context of TTd application. beta 2GPI-specific immune response is established as a part of TTd-specific immune response by molecular mimicry mechanism due to structural homology between TTd and beta 2GPI. This finding is supported by the following facts: (1) cross-reactive Abs that recognize both TTd and beta 2GPI epitopes are present in Balb/c mice sera; (2) anti-TTd Abs secretion in splenic cultures is induced after beta 2GPI stimulation and vice versa. However, analyses of (1) IL-10 production following in vitro stimulation of immunized Balb/c mice splenocytes by TTd, beta 2GPI or glutaraldehyde-treated beta 2GPI and (2) specific impact of ConA and agonists of TLR2, TLR4, and TLR9 on anti-TTd and autoreactive Abs secretion strongly imply that these two branches of the TTd-induced immune response do not use identical cell populations and are regulated in a different way. Results presented in this paper describe that structural homology between foreign and self-antigens could focus mounted autoreactive immune response toward specific self-structure, but the context of antigen application, including a history of previous immune stimulations and adjuvants applied together with the antigen, are the main factors which determine the outcome of the induced immune response
Gonadal hormone dependent developmental plasticity of catecholamine:beta 2-adrenoceptor signaling complex in male rat thymus: Putative implications for thymopoiesis
The study was undertaken considering that: i) androgens affect beta(2)-adrenoceptor (AR)-mediated catecholamine (CA) action in many tissues; and ii) peripubertal changes in both circulating androgen and thymic CA levels are implicated in rat thymic involution. Its aims were to: i) explore putative effects of the late prepubertal orchidectomy on thymic CA:beta(2)-AR complex in young adult rats, and ii) delineate the direct effects of testicular hormone withdrawal on the CA:beta(2)-AR complex from those elicited secondarily through altered influence of this complex components on each other's availability. Upon showing that prepubertal orchidectomy augmented the efficacy of thymopoiesis through increasing the thymocyte surface density of Thy-1, whose expression is negatively regulated by beta(2)-AR-mediated signaling, we examined the effects of orchidectomy and 14-day-long propranolol (PROP) treatment in orchidectomized (ORX) and sham-ORX rats on thymic norepinephrine (NE) concentration and metabolism and beta(2)-AR expression. Orchidectomy, despite an increase in the average NE amount per thymocyte and total thymocyte NE content diminished thymic NE concentration. This decrease reflected the diminished density of CA-synthesizing nerve fibers, CD68 + macrophages, cortical (aminopeptidase A+), and medullary (UEA-1+) thymic epithelial cells (TECs) and their CA content (probably due to lessened TH expression accompanied by increased MAO-A expression). Moreover, orchidectomy decreased the surface beta(2)-AR expression on thymocytes, CD68+ macrophages and OX-62+ dendritic cells, but increased its expression on the TECs. In sham-ORX rats, PROP reduced thymic NE concentration by diminishing TH expression in the thymic cells. Additionally, PROP in thymocytes and thymic stromal cells diminished and enhanced the beta(2)-AR mRNA expression, respectively. However, in ORX rats PROP did not significantly affect CA(NE):beta(2)-AR complex components. This indicated that prepubertal orchidectomy affects ability of young adult rats to respond to beta-AR blockade by altering thymic NE and beta(2)-AR availability. Collectively, the results showed that testicular hormones contribute to alterations in thymus/thymopoiesis during the critical peripubertal period by shaping modulatory sympathetic influence and CA autocrine/paracrine action within the organ. (C) 2013 Elsevier B.V. All rights reserved
Binding affinity between dietary polyphenols and beta-lactoglobulin negatively correlates with the protein susceptibility to digestion and total antioxidant activity of complexes formed
Non-covalent interactions between beta-lactoglobulin (BLG) and polyphenol extracts of teas, coffee and cocoa were studied by fluorescence and CD spectroscopy at pH values of the gastrointestinal tract (GIT). The biological implications of non-covalent binding of polyphenols to BLG were investigated by in vitro pepsin and pancreatin digestibility assay and ABTS radical scavenging activity of complexes formed. The polyphenol-BLG systems were stable at pH values of the GIT. The most profound effect of pH on binding affinity was observed for polyphenol extracts rich in phenolic acids. Stronger non-covalent interactions delayed pepsin and pancreatin digestion of BLG and induced beta-sheet to alpha-helix transition at neutral pH. All polyphenols tested protected protein secondary structure at an extremely acidic pH of 1.2. A positive correlation was found between the strength of protein-polyphenol interactions and (a) half time of protein decay in gastric conditions (R-2 = 0.85), (b) masking of total antioxidant capacity of protein-polyphenol complexes (R-2 = 0.95)