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Polymorphisms of the Prion Protein Gene (PRNP) in a Serbian Population
No full textPrion diseases are a group of etiologically heterogenous neurodegenerative disorders. We have analyzed the coding region of PRNP gene in 121 healthy citizens of Serbia to determine whether the frequencies of M129V, E219K, and octapeptide repeat number polymorphism. For Serbian population, polymorphism of PRNP gene at codon 129 does not differ from healthy European populations. Also codon 219 is monomorphic for the Glu allele both in Serbian population and other European populations. On the contrary, in Serbian population we did not detect any deletions or insertions in octapeptide repeat region, whereas deletions were detected in other European populations
Network connectivity is shown to change in C57BL/6 mice during a continuing immune response subsequent to tetanus toxoid hyperimmunization
Get PDFWe have already demonstrated (Stojanovic et al., 2009) a connection between tetanus toxoid (TTd) hyperimmunization and the induction of anti-phospholipid syndrome (APS) in BALB/c mice. Here we show that C57BL/6 mice subjected to an identical procedure do not exhibit any like pathology attributable to anti-phospholipid antibodies; we explain that this absence results from idiotypic connectivity. Six groups of C57BL/6 mice were hyperimmunized with TTd in aluminum hydroxide or glycerol, with or without pretreatments. Pretreated mice had been injected with polyclonal or nonspecific immune stimulators, such as complete Freund's adjuvant (CFA) or glycerol. The epitope specificity of induced antibodies was tested by indirect ELISA using a tetanus toxoid immunogen and these autoantigens: phospholipids, gangliosides, laminin. Idiotypic connectivity was tested by competitive ELISA and gauged from the degree to which the interaction of idiotypic/anti-idiotypic complementary antibodies was inhibited in the presence of immunized sera antibodies. Higher idiotypic connectivity was noted amongst pretreated mice. There was a positive correlation between higher connectivity and autoantibody levels that acted to favor the participation of natural autoantibodies in the inhibitory process. We conclude that idiotypic connectivity plays a protective role in immunization-induced autoimmunity
Sistemi skorovanja
No full textCharacterization and classification of injury severity quantify and unify the term of injury in clinical and research work. The beginnings of injury scoring date back to only about fifty years ago. The first individual scoring system, AIS (Abbreviated Injury Scale), was developed in 1969 and modified in 2005. This score served as the base for ISS (Injury severity score), mostly used for trauma severity assessment. As any other attempt to 'measure' the severity of injuries is rather difficult and imperfect, a number of scoring systems have been developed. This work is a review of the most frequently used anatomical and physiological scoring systems, as well as new ways in their development.Karakterizacija i klasifikacija težine povrede kvantifikuje i unificira pojam povređivanja u kliničkom i istraživačkom radu. Počeci skorovanja povreda datiraju od pre samo pedesetak godina. Prvi individualni skoring sistem, AIS (Abbreviated Injury Scale), razvijen je 1969. godine, a modifikovan 2005. g. Ovaj skor poslužio je kao baza za ISS (Injury severity score), najviše upotrebljavan skor za merenje težine traume. Kako je svaki pokušaj 'merenja' težine povreda dosta težak i nesavršen, razvijaju se mnogi skoring sistemi. Rad je revijalni prikaz najčešće upotrebljavanih anatomskih i fizioloških skoring sistema, kao i novih puteva u njihovom razvoju
Characterization of the bacteriocin-producing strain Lactobacillus paracasei subsp. paracasei BGUB9
Get PDFThe strain Lactobacillus paracasei subsp. paracasei BGUB9 that was isolated from traditionally homemade hard cheese produces bacteriocin designated as BacUB9, with an approximate molecular mass of 4 kDa. Biochemical characterization and the antimicrobial activity test of BacUB9 were performed. The onset of BacUB9 biosynthesis was observed at the end of an exponential phase of growth. Bacteriocin UB9 retained the antimicrobial activity within the pH range from 1 to 10 and after treatment at 100oC for 30 min. The bacteriocin is susceptible to the activity of proteolytic enzymes. Bacteriocin BacUB9 has a very narrow antimicrobial spectrum, limited to several strains that belong to closely related species. The effect of BGUB9 on the growth of the strain Lactobacillus paracasei subsp. paracasei BGHN14 in a mixed culture was monitored. The mode of action of BacUB9 on the strain BGHN14 was identified as bacteriostatic. Plasmid curing results indicated that a plasmid, designated as pUB9, seemed to be responsible for both bacteriocin BacUB9 production and host immunity
Increased efficency of a1- adrenoceptor mediated thymopoesis in old rats
No full textWe examined influence of aging on: i) a1- AR expression on thymocytes and ii)
a1-AR mediated modulation of thymopoiesis. Using immunocytochemical and
flow cytometric analysis (FCA) of a1-AR expression on thymocytes from young
(2 m.) and old (18 m.) Wistar rats, an increase in a1-AR density on thymocytes
with advancing age was demonstrated. Age-associated plasticity of a1-AR
mediated tuning of T-cell development was assessed by FCA of thymocyte phenotypic profile following 14-day-long treatment with a1-AR blocker urapidil in
young and old rats. Urapidil augmented thymocyte number in rats of both
ages, but this increase reached statistical significance only in young rats.
Affecting generally the same thymocyte differentiational points (transition from
CD4+CD8+TCRab- to CD4+CD8+TCRablow stage, thymocyte selection and
lineage commitment), but with distinct efficiency, irrespective of age, urapidil
led to divergent changes in relative number of the most mature single positive
cells. Urapidil increased the percentage of CD4+CD8-TCRabhigh, but
decreased that of CD4-CD8+TCRabhigh cells. In old rats, differently from
young rats (showing increase in Thy-1 surface density), there were no changes
in Thy-1 expression (most likely due to a diminished central sympatholitic action
of urapidil), and presumably related efficiency of thymocyte selection processes,
suggesting an increased effectiveness of a1-AR mechanisms in old
rat thymus. To further support this hypothesis were findings demonstrating a
more pronounced urapidil-induced increase in relative number of thymocytes
with regulatory phenotype (CD4+CD25+RT6.1- and CD161+TCRab+) with
advancing age. In conclusion, changes in efficiency of modulatory thymic
a1-AR-mediated mechanisms may contribute to age-associated remodelling
of thymopoiesis
Age-associated plasticity of alpha 1-adrenoceptor-mediated tuning of T-cell development
No full textAlpha(1)-adrenoceptors (alpha(1)-ARs) are involved in neuro-thymic and thymic intercellular communications, and consequently modulation of T-cell development. Ageing is associated with a number of changes in noradrenergic neuro-effector transmission, and possibly intercellular noradrenaline (NA)-mediated communication resulting in altered responses of target cells to NA. Thus, in old animals an altered NA modulation of thymopoiesis via alpha(1)-ARs may be expected. To test this hypothesis, in old and young adult Wistar rats we examined: 1) thymic NA levels, density of noradrenergic innervation and NA synthesizing cells, as well as alpha(1)-AR expression, and 2) then the effects of 14-day-long treatment with the alpha(1)-AR blocker, urapidil, on thymocyte development. Overall, the first part of study suggested augmented NA signalling to thymic cells via alpha(1)-ARs due to increased NA availability and alpha(1)-AR thymocyte surface density in old rats. The second part of study supported this assumption. Namely, although in rats of both ages urapidil affected the same thymocyte developmental steps ultimately leading to changes in the relative number of the most mature single positive TCR alpha beta(high) thymocytes, its effects were generally more prominent in old animals. Following urapidil treatment, the percentages of CD4+CD8- cells, including those showing a regulatory CD4+CD25+RT6.1- phenotype, were increased, while CD4-CD8+ cells decreased. In old rats, an augmented thymic escape of immature CD4+CD8+ cells was also registered. In rats of both ages the thymic changes were accompanied by alterations in the proportions of major cell populations in the T-lymphocyte compartment of both peripheral blood and spleen, leading to an increase in the CD4+/CD8+ T-cell ratio. These alterations were also more pronounced in old rats. Moreover, in old rats following urapidil treatment the proportion of TCR alpha beta + cells in the periphery was slightly greater reflecting, most likely, partly enhanced thymic production of regulatory CD161 +TCR alpha beta + cells. Thus, the study indirectly suggests an age-associated increase in the basal alpha(1)-AR-mediated inhibitory influence of NA on thymopoiesis. (C) 2010 Elsevier Inc. All rights reserved
Digestibility and allergenicity assessment of enzymatically crosslinked beta-casein
No full textCrosslinking enzymes are frequently used in bioprocessing of dairy products. The aim of this study was to examine the effects of enzymatic crosslinking on IgE binding, allergenicity and digestion stability of beta-casein (CN). beta-CN was crosslinked by transglutaminase, tyrosinase, mushroom tyrosinase/caffeic acid and laccase/caffeic acid. The IgE binding to beta-CN was compared in vitro by CAP inhibition assay, ELISA inhibition as well as ex vivo by basophil activation assay. Crosslinked CNs were digested by simulated gastric fluid for 15 and 60 min and obtained digests analyzed for their ability to inhibit IgE binding by CAP inhibition assay and SDS-PAGE. The ability of crosslinked CNs to activate basophils was significantly reduced in seven patients in the case of CN crosslinked by laccase and moderately reduced in the case of tyrosinase/caffeic acid crosslinked CN (in two cow's milk allergy patients tested with different allergen concentrations). The response to various crosslinked CNs differed individually among patients' sera tested by ELISA inhibition assay. The presence of caffeic acid hampered digestion by pepsin, and this effect was most pronounced for the tyrosinase/caffeic acid crosslinked CN. The laccase/caffeic acid and mushroom tyrosinase/caffeic acid had the highest potential in mitigating IgE binding and allergenicity of the beta-CN out of all investigated enzymes. The presence of a small phenolic compound also increased digestion stability of beta-CN
Changes in Composition of IgM Polymers in Patients Suffering from Recurrent Urinary Bacterial Infections after Bacterial Immunization Treatment
No full textIgM is the first antibody produced during the immune response to infection or immunization, and it can be secreted as pentamer (containing a small polypeptide, termed as J chain) or hexamer (lacking J chain). In this paper we have analyzed structural characteristics (by electrophoresis and immunoblot) and anti-bacterial specificity (by enzyme-linked immunosorbent assay) of IgM antibodies purified from female patients suffering from recurrent bacterial infections of lower urinary tract and therapeutically immunized with the mixture of heat-inactivated uropathogenic bacteria. We report on changes in the composition of IgM polymers in tested patients. The immunization induced the raise of the levels of hexamers in patients that did not respond to immunization (non-responders), while the IgM polymers remained on the pentameric level in immunization dependent responders. We propose that the composition of IgM polymers could influence the immunization outcome and should be taken in count regarding the treatment of recurrent bacterial infections