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R Toman

Publications and source records attributed to R Toman.

At least 19 recordsLinked to original sources
PubMed2006

Induction of tumor necrosis factor alpha in murine macrophages with various strains of Coxiella burnetii and their lipopolysaccharides.

The ability of various strains of Coxiella burnetii (C.b.) and their phase I and II lipopolysaccharides (LPSs) to induce tumor necrosis factor alpha (TNF-alpha) in peritoneal Balb/c mouse macrophages in vitro was investigated. Considerable differences in the induction ability were observed in dependence on the strain applied. In a TNF-alpha bioassay, the most effective inducers were both corpuscles and LPSs of the strains Priscilla and Scurry, followed by Nine Mile, Luga, and Henzerling I. In contrast, in ELISA, the most effective inducers were LPSs of the strains Luga and Henzerling, followed by Nine Mile, Priscilla, and Scurry. The role of toll-like receptor 4 (TLR4) in the induction was confirmed by the use of C3H/HeJ mouse macrophages. Thus, the induction of TNF-alpha was much higher in Balb/c mouse macrophages than that in TLR4-deficient C3H/HeJ mouse macrophages. Differences in the results of the bioassay and those of ELISA suggest a role of another secreted factor(s) induced with C.b. in murine macrophages that could act synergically with TNF-alpha in L929 cells in the bioassay. The observed differences in TNF-alpha induction might play a role in the pathobiology of Q fever.

Animals↗
PubMed2005

Fertility and content of cadmium in pheasant (Phasianus colchicus) following cadmium intake in drinking water.

In this study, the effects of cadmium applied per os on fertility, live weight of newly hatched chicks, and cadmium concentrations in some organs of young and adult pheasants were investigated. The metal was applied at the concentration of 1.5 mg Cd(2+)/L during 3 months. After the egg laying, the numbers of eggs laid, cracked, and unfertilized were determined and the live weights of newly hatched chicks were measured. The cadmium concentrations in liver, kidney, and muscle (m. pectoralis) of young and adult pheasants were analyzed. We found that cadmium exposure of the adults did not affect the number of eggs laid but resulted in more eggs being damaged. Hatchlings were significantly heavier in the cadmium-treated group (21.36 +/- 2.28 g) compared to the control group (20.91 +/- 1.97 g) 4 weeks after the cadmium intake. Higher cadmium concentrations were observed in the muscle and kidney tissue of newly hatched pheasants after 4 weeks compared to the cadmium-exposed groups after 8 and 12 weeks. The cadmium concentrations in kidneys and liver increased significantly in adult pheasants. The metal had accumulated especially in kidneys of the adult pheasants and reached levels up to 9.64 mg/kg wet weight 3 months after the daily cadmium intake in drinking water. The concentration in liver of the adults was 3.53 mg/kg wet weight.

Animals↗
PubMed2005

Efficiency of various serological techniques for diagnosing Coxiella burnetii infection.

An indirect immunofluorescence assay (IFA) using a recently developed commercial kit for detecting antibodies against Coxiella burnetii (C.b.), the etiological agent of Q fever, has been evaluated using human field serum samples. The IFA was compared with an ELISA and a complement fixation test (CFT). The IFA was based on the corpuscular C.b. phase I and phase II antigens specific to anti-C.b. phase I and II antibodies, respectively. Fifty sera from persons with symptoms of Q fever were examined in this study. The IFA compared with the ELISA showed the sensitivities of 97.7% and 87.2% for IgG and 66.7% and 60.0% for IgM phase II and I antibodies, respectively and the specificities of 100% and 90.0% for IgG and 75.9% and 64.7% for IgM phase II and phase I antibodies, respectively. Due to a limited number of sera positive in the IgA antibody testing, the data presented should be considered with caution. It appears that the IFA strikes a very good balance between high specificity and sensitivity with phase II and phase I IgG antibodies and a less satisfactory one with IgM antibodies. The CFT failed in one of the above aspects showing a good specificity but a poor sensitivity, especially for phase I antibodies. The study demonstrated that the IFA is suitable for diagnosing Q fever and its therapeutic follow-up and is a good candidate for screening sera in large numbers. A certain limitation, especially in testing early stages of the chronic disease, could be a low fluorescence intensity of the IgA positive control in comparison with the IgA negative one.

Antibodies, Bacterial↗
PubMed2005

Analysis of specificity of interaction between synthetic key saccharide components of lipopolysaccharides and monoclonal antibodies to Coxiella burnetii.

Two monoclonal antibodies (MAbs) against the lipopolysaccharides (LPSs) of Coxiella burnetii (C.b.) strains Priscilla and Nine Mile were prepared characterized by their interaction with synthetic glycoconjugates representing parts of LPSs of C.b. in virulent phase. Both MAbs were directed against immunodominant epitopes comprising core constituent of LPSs, Kdo (3-deoxy-alpha-D-manno-2-octulo-pyranosylonic acid). ELISA showed that the anti-Nine Mile MAb 4/11 bound preferably to disaccharides (alpha-Kdo (2 --> 4) alpha-Kdo and alpha-Kdo (2 --> 4) alpha-(5d) Kdo), while the anti-Priscilla MAb 1/4/H bound to all conjugates, though with various intensity. On the other hand, immunoelectron microscopy revealed a positive binding of only one glycoconjugate, namely the trisaccharide alpha-Kdo (2 --> 4) alpha-Kdo (2 --> 4) alpha-Kdo-BSA, to both MAbs. In competitive ELISA (cELISA), the anti-Priscilla MAb 1/4/H distinguished the strains Nine Mile and Priscilla, while the anti Nine Mile MAb 4/11 did not.

Animals↗
PubMed2004

Initial peptide mass fingerprinting analysis of proteins obtained by lysis of Coxiella burnetii cells.

Whereas the complete genome of Coxiella burnetii (C.b.), the etiological agent of Q-fever, has recently been published (Seshadri et al., Proc. Natl. Acad. Sci. USA. 100, 5455-5460, 2003), the C.b. proteome is still under study. Using the bioinformatic approach, we found in total 309 proteins on two dimensional electroctrophoretic images of C.b. whole cell lysates. Eighteen major protein species were subjected to peptide mass fingerprinting and identified as the products of 6 known open reading frames (ORFs): the chaperone DnaK (heat shock 70 K protein), chaperonin 60 K (GroEL protein, heat shock protein B), DnaJ-like protein djlA (mucoidy activation protein mucZ), elongation factor Ts (EF-Ts), ribosomal protein L7/L12, and chaperonin 10 K (GroES protein, heat shock protein A).

Bacteria↗
PubMed2004

Concentration of copper, iron, zinc, cadmium, lead, and nickel in bull and ram semen and relation to the occurrence of pathological spermatozoa.

In this study the concentration of copper, iron, zinc, cadmium, lead, and nickel in bull and ram semen and relation of these metals to spermatozoa morphology was investigated. Analysis by atomic absorption spectrophotometry showed that copper concentration was significantly higher (p<0.0001) in ram semen in comparison with bull semen. The zinc concentration was higher in bull semen in comparison with ram semen. The iron and cadmium concentrations in the semen were similar. Higher concentration of lead was found in ram semen. Higher levels of nickel were found in ram semen in comparison with bulls. In bull semen 11.79+/-4.88% of pathological spermatozoa was found. Higher occurrence of pathological spermatozoa was in ram semen (17.17+/-3.76) in comparison with the semen of bulls. Separated tail, tail torso, and knob twisted tail were the most frequent forms of pathological spermatozoa in both species. Correlation analysis in bulls showed high positive relation between iron and zinc (r = 0.72), nickel and separated tail (r = 0.76), separated tail and tail torso (r = 0.71), tail torso and total number of pathological spermatozoa (r=0.72), and between tail ball and total number of pathological spermatozoa (r = 0.78). In rams high positive correlation between cadmium and lead (r=0.98), nickel and separated tail (r=0.77), separated tail and total number of pathological spermatozoa (r=0.69), knob twisted tail and retention of cytoplasmic drop (r=0.78), and between knob twisted tail and other pathological spermatozoa (r = 0.71) was found. High negative correlation in ram semen was observed between copper and nickel (r=0.71), copper and separated tail (r=0.70), and between iron and tail torso (r=0.67). The results suggest that the studied metals have a direct effect on spermatozoa quality.

Animals↗
PubMed2003

Seminal concentrations of trace elements in various animals and their correlations.

AIM: To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. METHODS: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. RESULTS: The seminal copper concentration was significantly higher in ram [(2.49+/-0.18) mg/kg] and fox [(2.16+/-0.53) mg/kg] than that in bull [(1.64+/-0.21) mg/kg], boar [(1.64+/-0.28) mg/kg] and stallion (0.86 mg/kg). In boar a significantly higher seminal zinc concentration (171.74+/-65.72) mg/kg] was found in comparison with stallion [(86.20+/-45.88) mg/kg], bull [(83.15+/-61.61) mg/kg], ram [(60.46+/-35.37) mg/kg] and fox (13.09+/-5.22) mg/kg]. The iron concentration in semen was significantly higher in ram [(40.32+/-10.81) mg/kg), bull [(38.04+/-22.07) mg/kg] and fox [(33.16+/-24.36) mg/kg] than that in boar [(16.14+/-10.35) mg/kg] and stallion (12.68 mg/kg). The seminal cadmium concentration was relatively low [(0.05~0.12) mg/kg] in all studied species. The seminal lead concentration was the highest in ram [(0.35+/-0.68) mg/kg], which was much higher than in fox [(0.08+/-0.06) mg/kg], bull [(0.06+/-0.04) mg/kg], stallion [(0.05+/-0.05) mg/kg] and boar [0.02+/-0.03) mg/kg]. The level of seminal nickel was significantly higher in fox [(0.35+/-0.24) mg/kg] and ram [(0.31+/-0.19) mg/kg] in comparison with bull [(0.12+/-0.07) mg/kg] and boar [(0.06+/-0.08) mg/kg]. The concentration of nickel in the semen of stallion was (0.20 +/-0.24) mg/kg. There was a high positive correlation between seminal iron and zinc in bull (r=0.723) and stallion (r=0.723), between cadmium and lead in ram (r=0.976) and boar (r=0.973) and between iron and cadmium (r=0.783) and iron and lead (r=0.791) in boar. A high negative correlation between seminal nickel and copper in ram (r=-0.709) and between seminal copper and lead in fox (r=-0.854) was found. CONCLUSION: There are significant differences in the concentrations of seminal elements in different animals. There is a high concentration of seminal copper in ram and fox, a high zinc level in boar, a high iron level in bull, ram and fox and a high nickel level in ram and fox.

Animals↗
PubMed2002

Analysis of phospholipids from Coxiella burnetii by fast atom bombardment mass spectrometry. A rapid method for differentiation of virulent phase I and low virulent phase II cells.

Phospholipids extracted from the Coxiella burnetii strain Nine Mile virulent phase I and low-virulent phase II cells were directly analyzed by fast atom bombardment mass spectrometry (FAB-MS). Constant neutral loss (CNL) scanning mass spectra (MS) were acquired to identify various phospholipids within phospholipid classes. Phospholipids from the phase I C. burnetii cells were much more complex than those from the phase II cells. Moreover, in the latter, the absence of phospholipids of the phosphatidylinositol class could be noticed. The results indicate that CNL scanning of phospholipid samples provides a rapid and simple method for identification of the phase state of the bacterium.

Coxiella burnetii↗
PubMed2001

Structural analyses of the lipopolysaccharides from Chlamydophila psittaci strain 6BC and Chlamydophila pneumoniae strain Kajaani 6.

Lipopolysaccharides (LPSs) of Chlamydophila psittaci 6BC and Chlamydophila pneumoniae Kajaani 6 contain 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), GlcN, organic bound phosphate, and fatty acids in the molar ratios of approximately 3:2:2.2:4.8 and approximately 2.9:2:2.1:4.9, respectively. The LPSs were immunoreactive with a monoclonal antibody against a family-specific epitope of chlamydial LPS. This finding, together with methylation analyses of both LPSs and MALDI-TOF MS experiments on de-O-, and de-O,N-acylated LPSs, indicate the presence of a Kdo trisaccharide proximal to lipid A having a structure alpha-Kdo-(2-->8)-alpha-Kdo-(2-->4)-alpha-Kdo, which appears to be the main component of the core region in the native chlamydial LPSs. In the de-O-acylated LPSs from Chl. psittaci 6BC and Chl. pneumoniae Kajaani 6, two major molecular species are present that differ in distribution of amide-bound hydroxy fatty acids over both GlcN. It appears that either two (R)-3-hydroxy-18-methylicosanoic acids or one (R)-3-hydroxy-18-methylicosanoic acid and one (R)-3-hydroxyicosanoic acid are attached to the GlcN residues. In contrast, the de-O-acylated LPS of Chl. psittaci PK 5082 contains one major molecular species that has two (R)-3-hydroxyicosanoic acid residues attached to two GlcN residues.

Blotting, Western↗
PubMed2001

Isolation and evaluation of Coxiella burnetii O-polysaccharide antigen as an immunodiagnostic reagent.

A lipid A - deprived lipopolysaccharide (LPS) from Coxiella burnetii (C.b.) Priscilla strain in virulent phase I was separated by steric-exclusion chromatography and high performance liquid chromatography (HPLC). The isolated O-specific polysaccharide (PS) fractions were analyzed by different physico-chemical methods and showed noticeable differences in their overall composition. The antigenic potential of the PS fractions was evaluated by ELISA with animal and human sera and in comparison with those of the native C.b. LPSs and phase I and II C.b. Nine Mile stain cells of which the latter are routinely used in diagnosis of Q fever. The results indicate that the high molecular mass PS antigen SG501 could be used in ELISA for a sensitive and specific detection of anti-C.b. antibodies in the examined sera.

Antibodies, Bacterial↗
PubMed2000

alpha(v)beta(3) integrin and bacterial lipopolysaccharide are involved in Coxiella burnetii-stimulated production of tumor necrosis factor by human monocytes.

Coxiella burnetii, the agent of Q fever, enters human monocytes through alpha(v)beta(3) integrin and survives inside host cells. In addition, C. burnetii stimulates the synthesis of inflammatory cytokines including tumor necrosis factor (TNF) by monocytes. We studied the role of the interaction of C. burnetii with THP-1 monocytes in TNF production. TNF transcripts and TNF release reached maximum values within 4 h. Almost all monocytes bound C. burnetii after 4 h, while the percentage of phagocytosing monocytes did not exceed 20%. Cytochalasin D, which prevented the uptake of C. burnetii without interfering with its binding, did not affect the expression of TNF mRNA. Thus, bacterial adherence, but not phagocytosis, is necessary for TNF production by monocytes. The monocyte alpha(v)beta(3) integrin was involved in TNF synthesis since peptides containing RGD sequences and blocking antibodies against alpha(v)beta(3) integrin inhibited TNF transcripts induced by C. burnetii. Nevertheless, the cross-linking of alpha(v)beta(3) integrin by specific antibodies was not sufficient to induce TNF synthesis. The signal delivered by C. burnetii was triggered by bacterial lipopolysaccharide (LPS). Polymyxin B inhibited the TNF production stimulated by C. burnetii, and soluble LPS isolated from C. burnetii largely mimicked viable bacteria. On the other hand, avirulent variants of C. burnetii induced TNF production through an increased binding to monocytes rather than through the potency of their LPS. We suggest that the adherence of C. burnetii to monocytes via alpha(v)beta(3) integrin enables surface LPS to stimulate TNF production in THP-1 monocytes.

Bacterial Adhesion↗
PubMed2000

Phase variation of Coxiella burnetii strain Priscilla: influence of this phenomenon on biochemical features of its lipopolysaccharide.

During the phase variation of Coxiella burnetii, modifications in its lipopolysaccharide (LPS) component were investigated. The cloned phase I C. burnetii cells were passed serially in chicken embryo yolk sacs up to the egg passage (EP) 90. The LPSs from the cells in EPs 3, 12, 21, 40, 60, and 90 were all separated by steric exclusion chromatography into three major populations: the high, intermediate, and low molecular weight fractions, differing one from another in size and chemical composition. No noticeable shortening of the O-polysaccharide chains was observed in the LPSs isolated during the C. burnetii cultivation. However, a redistribution of the existing LPS populations has been observed due to an increasing prevalence of those cells in the whole cell population that express LPS molecules with truncated O-chains and those being of R-type. In the high and intermediate molecular weight LPS populations, virenose and dihydrohydroxystreptose are lost gradually with the progress in phase variation. This occurs more readily with the former sugar. At present, the molecular mechanisms influencing the LPS modifications during the C. burnetii phase variation remain unclear.

Animals↗
PubMed1999

Distribution of cadmium in selected organs of mice: effects of cadmium on organ contents of retinoids and beta-carotene.

Cadmium was administered to 32 adult ICR mice i.p. in two single doses (0.25 and 0.5 mg CdCl2, per kg of b.w.). After 48 hours concentrations of cadmium in kidneys, liver, spleen, muscle (m. quadriceps femoris), ovaries and testes and the concentration of retinyl palmitate, retinol and beta-carotene in kidney, liver and testes were determined. Significantly higher cadmium concentration was found in liver, kidney and ovary in both experimental groups in comparison with the control group (p<0.001). In muscle, spleen and testis the cadmium level was higher, however not significantly. No significant differences in the concentration of retinyl palmitate, retinol and alpha-carotene in liver were found. Concentration of alpha-carotene in kidney and testis was significantly decreased in both groups administered with cadmium (p<0.001). Concentration of retinyl palmitate was significantly lower in testis in the group with higher cadmium level (p<0.001) and the concentration of retinol significantly decreased in kidney and testis of mice after an administration of 0.5 mg CdCl2/kg b.w.

Animals↗
PubMed1999

Chlamydia psittaci lipopolysaccharide. A reinvestigation of its chemical composition and structure.

A lipopolysaccharide (LPS) of Chlamydia psittaci PK 5082 strain associated with enzootic abortion in ewes was isolated from embryonated hen eggs-grown elementary bodies (EBs) by a phenol/water procedure. Compositional analyses revealed the presence of 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo), glucosamine (GlcN), phosphorus, and fatty acids in a molar ratio of 2.6:2.0:2.4:4.4. GlcN was the only amino sugar detected. Methylation analysis of the LPS confirmed the presence of a Kdo trisaccharide proximal to lipid A having the structure Kdo-(2-->8)-Kdo-(2-->4)-Kdo, which appears to be a highly conserved region in native chlamydial LPSs. The complex fatty acid composition revealed the presence of ten different straight or branched (iso and anteiso) nonhydroxy fatty acids and thirteen 3-hydroxy fatty acids. The major nonhydroxy fatty acid was icosanoic acid and the most prominent 3-hydroxy fatty acid was 3-hydroxyicosanoic acid followed by 3-hydroxy-18-methylicosanoic acid. The 3-hydroxy fatty acids represented more than two thirds of the total fatty acid content and most of them were bound in amide linkages. In contrast, most nonhydroxy fatty acids were ester-linked. It appears that LPSs from various chlamydial species differ in fatty acid composition and distribution.

Animals↗
PubMed1998

NMR study of virenose and dihydrohydroxystreptose isolated from Coxiella burnetii phase I lipopolysaccharide.

A lipopolysaccharide (LPS) isolated from Coxiella burnettii in virulent phase I contains in its O-polysaccharide chain two unusual sugars, virenose (6-deoxy-3-C-methylgulose) and dihydrohydroxystreptose [3-C-(hydroxymethyl)lyxose]. The sugars were isolated from LPS I, after acid hydrolysis and removal of lipid A, by a combination of HPLC and preparative paper chromatography. Their enantiomeric forms and ring conformations were established from optical rotation and NMR data. Two-dimensional COSY, HSQC, and HMBC as well as one- and two-dimensional NOEs were used to assign all proton and carbon signals in both monosaccharides. Virenose was found to be the D-gulo enantiomer with the 4C1 ring conformation and dihydrohydroxystreptose was shown to be the L-lyxo enantiomer also with the 4C1 conformation. The latter sugar was reported [S. Schramek, J. Radziejewska-Lebrecht, and H. Mayer, Eur. J. Biochem., 148 (1985) 455-461] to be present in LPS I in a furanose form, and it appears that a furanose to pyranose tautomerization took place in the course of the isolation procedure.

Carbohydrate Conformation↗
PubMed1996

Structural study on a lipopolysaccharide from Coxiella burnetii strain Nine Mile in avirulent phase II.

A lipopolysaccharide isolated from Coxiella burnetti strain Nine Mile in avirulent phase II contains in the lipid A proximal region D-mannose, D-glycero-D-manno-heptose, and 3-deoxy-D- manno-oct-2-ulosonic acid (Kdo) in the molar ratio 2:2:3. The primary structure 1 of the heptasaccharide was determined by glycose analysis, methylation analysis, ESI-MS, and FABMS. [sequence: see text]

Carbohydrate Conformation↗