Epidemiology of Staphylococcus pseudintermedius in cats in Poland

Staphylococcus pseudintermedius is a well-known coagulase-positive staphylococcus that is mainly associated with the asymptomatic colonization of the skin of pets and mucous membranes. Little is still known about the occurrence of S. pseudintermedius in cats. The current study aimed to characterize the isolates of S. pseudintermedius from sick and healthy cats. This was achieved by examining their antibiotic resistance properties, biofilm formation, and genotype differences. Six hundred and seventy-six cats were swabbed (595 healthy and 81 sick cats). Thirty-five distinct S. pseudintermedius isolates from 27 cats were isolated. The prevalence of S. pseudintermedius in healthy and sick cats was 2.49% and 7.61%, respectively. In comparison, MRSP (methicillin-resistant Staphylococcus pseudintermedius) prevalence was 0.12% and 2.98%, respectively. Cats were more frequently colonized with S. pseudintermedius when kept with dogs, regardless of their health condition, with this result being statistically significant. Multidrug resistance was detected in 50%, and 38.46% of S. pseudintermedius isolates from healthy and sick cats, respectively. In contrast, genetic multidrug resistance was detected in 59% and 46.15% cases, respectively. Seven from eight isolated MRSPs were multidrug-resistant. Multi-locus sequence typing (MLST) assigned isolates to 19 types, of which 16 types submitted for the first time to the PubMLST database. The most frequently detected STs (sequence types) were 551 and 71. ST71 and ST551 were mainly isolated from cats with clinical signs of infection. All were MRSPs, regardless of cats’ health. These isolates were characterized with the most frequent antibiotic resistance at the phenotypic and genotypic level.

Identification of linear epitopes on the flagellar proteins of Clostridioides difficile

Clostridioides difficile (C. difficile) is an opportunistic anaerobic bacterium that causes severe diseases of the digestive tract of humans and animals. One of the possible methods of preventing C. difficile infection is to develop a vaccine. The most promising candidates for vaccine antigens are the proteins involved in the adhesion phenomena. Among them, the FliC and FliD are considered to be suitable candidates. In this paper, the FliC and FliD protein polypeptide epitopes were mapped in silico and by using PEPSCAN procedure. We identified four promising epitopes: ¹¹⁷QRMRTLS¹²³, ²⁰⁵MSKAG²⁰⁹ of FliC and ²²⁶NKVAS²³⁰, ³⁰⁶TTKKPKD³¹² of FliD protein. We showed that ¹¹⁷QRMRTLS¹²³ sequence is not only located in TLR5-binding and activating region, as previously shown, but forms an epitope recognized by C. difficile-infected patients' antibodies. ²⁰⁵MSKAG²⁰⁹ is a C. difficile-unique, immunogenic sequence that forms an exposed epitope on the polymerized flagella structure which makes it a suitable vaccine antigen. ²²⁶NKVAS²³⁰ and ³⁰⁶TTKKPKD³¹² are well exposed and possess potential protective properties according to VaxiJen analysis. Our results open the possibility to use these epitopes as suitable anti-C. difficile vaccine antigens.

Nasal carriage of various staphylococcal species in small ruminant lentivirus-infected asymptomatic goats

The study was carried out in Polish goat population to estimate the prevalence of the nasal cavity infection with various staphylococcal species including methicillin-resistant Staphylococcus aureus(MRSA), investigate the potential permissive role of small ruminant lentivirus (SRLV) infection and determine the level of clonality of S. aureus nasal isolates. Nasal swabs and blood samples were collec-ted from 1300 clinically healthy adult goats from 21 Polish goat herds. Blood samples were serological-ly screened for SRLV. Staphylococci were isolated from nasal swabs and identified using classical microbiological methods, MALDI-TOF, multiplex-PCR, and their clonality was assessed using PFGE. Antimicrobial resistance was determined on the basis of minimum inhibitory concentration and by demonstration of the presence of the mecA gene encoding the multiplex-PCR PBP2a protein and of the five main types of staphylococcal cassette chromosome mec. The apparent prevalence of staphylococ-cal and S. aureus infection of the nasal cavity was 29.1% (CI 95%: 26.9%, 31.5%) and 7.3% (CI 95%: 6.1%, 8.8%), respectively. No relationship was found between the SRLV-infection and the presence of any staphylococcal species including S. aureus (p=0.143). Only 9.8% of S. aureus isolates were resistant to amoxicillin/clavulanic acid and 5.9% to chloramphenicol and ciprofloxacin. All tested isolates proved to be phenotypically and genotypically sensitive to methicillin, which yielded the appar-ent prevalence of MRSA of 0% (CI 95%: 0%, 7.0%). S. aureus isolates show high genetic similarity within goat herds, however vary considerably between herds. Goats do not appear to be an important source of S. aureus for humans in Poland.

Prevalence of Staphylococcus Species Colonization in Healthy and Sick Cats

Staphylococcus is one of the most frequently isolated genera of opportunistic bacteria in animals and human beings. Staphylococci in mammals mostly inhabit the skin and mucous membranes. The objectives of the study were to investigate the distribution of staphylococcal species in healthy and sick cats in order to find diagnostic markers. The risk factors associated with colonization were also explored. Isolates from healthy (n=520) and sick cats (n=67) were identified at the species level using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Swabs from conjunctival sacs, nares, skin, anus, and wounds were investigated using this technique. The diversity of the Staphylococcus species was high: 26 and 17 species in healthy and sick cats, respectively, and predominantly coagulase-negative staphylococci (CoNS) were isolated. The most frequently observed were S. felis and S. epidermidis in healthy cats, whereas S. felis and S. haemolyticus were most often found in sick animals. S. aureus strains were only isolated from healthy cats, whereas the only coagulase-positive Staphylococcus (CoPS) which occurred in the sick cats group was S. pseudintermedius. The sick, more frequently than the healthy animals, were colonized with S. pseudintermedius and S. haemolyticus and the relationship was statistically significant. Mostly, regardless of the state of their health, similar Staphylococcus species were isolated from cats; therefore, particular attention should be paid during the interpretation of diagnostic results.

Advanced glycation end products as a source of artifacts in immunoenzymatic methods

The most abundant proteins in the arteries are those of extracellular matrix, ie. collagen and elastin. Due to their long half-lifes these proteins have an increased chance to undergo glycation. The aim of this study was to determine relationship between the content of the main extracellular matrix proteins and the advanced glycation end products (AGEs) in arteries. In this study 103 fragments of aorta were analyzed by ELISA and immunobloting for the content of collagens type I, III and IV and elastin and the content of advanced glycation end-products (AGE). A negative correlation between the content of collagens type III and IV and AGE (r = -0,258, p = 0,0122, and a weak negative correlation between collagen type III and age of the sample donor (r = 0,218, p = 0,0262) were demonstrated. This result comes as a surprise and it contradicts an intuitive assumption that with more glycation substrate, i.e. matrix proteins, more AGE products are expected. We have concluded that the results of the ELISA tests must have been influenced by the glycation. As a consequence, either modified protein molecules were not being recognized by the antibodies, or the glycation, and formation of crosslinks have blocked access of the antibodies to the antigen. It will conceal the effect of the linear dependence between the result (absorbance/densitometry) from the quantity of protein to which the antibody is directed.

Expression of advanced glycation end-products and NFκB in chick embryos exposed to dioxins and treated with acetylsalicylic acid and α-tocopherol

Dioxins have adverse and multifaceted effect on body functions. They are known to be carcinogens, immunotoxins, and teratogenic agents. In vivo, transformation of dioxins occurs after their interaction with the aryl hydrocarbon receptor (AhR) and leads to formation of proinflammatory and toxic metabolites. The aim of this study was to verify whether α-tocopherol (vitamin E) and acetylsalicylic acid (ASA), could reduce the damage caused by the action of dioxins. Fertile chicken eggs were injected with a solution of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), followed by the injection of α-tocopherol or acetylsalicylic acid. Organs such as heart and liver were dissected from the chick embryos at d 13 and 19 of development and subjected to immunohistochemical analysis of presence of advanced glycation end products (AGEs) and nuclear factor kappa B (NFκB) in tissues. The AGEs were used as the marker for exposure to dioxins, since it is well established that their level increases in dioxin-damaged tissues. Formation of AGEs was evaluated in embryos exposed to dioxin and treated with vitamin E and/or ASA (against dioxin-exposed, untreated controls). We have found that TCDD causes developmental disorders and increases the level of AGEs in chick embryo tissues. The use of such pharmacological agents as vitamin E, ASA, and combination of ASA and vitamin E, inhibited formation of the AGEs in 13-day-old embryos and reduced the AGEs level in embryos after 19 d of the development.

Glycation of Matrix Proteins in the Artery Inhibits Migration of Smooth Muscle Cells from the Media to the Intima

Formation and growth of atherosclerotic plaques have serious clinical consequences. One mechanism that occurs during atherogenesis is migration of smooth muscle cells from the middle layer of the artery to the intima, where they proliferate and are transformed into foam cells. This degenerative process is accompanied by glycation, by which proteins are modified and change the biomechanical and biochemical properties. The aim of the study was to determine whether glycation of collagen and elastin building the walls of blood vessels alters the adhesion and rate of myocyte migration. In vitro experiments included migration assays and immunocytochemical staining with anti α-actin, β-catenin anti-collagen type IV antibodies. It turns out that there is a tendency to decrease the number of cells that had migrated through the barrier consisting of glycated proteins as compared to the control. Adversely, the morphology of the cells cultured in the presence of glycated substrates is changed. The lower intensity of β-catenin staining indicates lower adhesiveness of such cells. It is proposed that glycation inhibits migration of smooth muscle cells from the media to the intima, which represents part of the anti-atherogenic mechanism.

Application of zwitterionic detergent to the solubilization of Klebsiella pneumoniae outer membrane proteins for two-dimensional gel electrophoresis

Klebsiella pneumoniae is a frequent cause of nosocomial respiratory, urinary and gastrointestinal tract infections and septicemia with the multidrug-resistant K. pneumoniae being a major public health concern. Outer membrane proteins (OMPs) are important virulence factors responsible for the appropriate adaptation to the host environment. They constitute of the antigens being the first in contact with infected organism. However, K. pneumoniae strains are heavily capsulated and it is important to establish the OMPs isolation procedure prior to proteomics extensive studies. In this study we used Zwittergent Z 3-14® as a detergent to isolate the OMPs from K. pneumoniae cells and resolve them using two-dimensional electrophoresis (2-DE). As a result we identified 134 protein spots. The OMPs identified in this study are possible candidates for the development of a protein-based vaccine against K. pneumoniae infections.

Increase in serum platelet-derived growth factor (PDGF)-BB reflects lymph node involvement in esophageal cancer patients independently from platelet count

AIM

To evaluate clinical significance and diagnostic utility of increase in serum PDGF-BB (sPDGF-BB) in esophageal cancer, which have not been addressed yet despite the relevance of PDGF axis in this cancer type.

METHODS

Immunoenzymatically assessed sPDGFBB was related to clinicopathological features, and inflammatory, angiogenic, and lymphangiogenic indices in 84 patients with esophageal cancer and 47 controls. Its diagnostic utility was evaluated by receiver operating characteristics (ROC) curve analysis.

RESULTS

sPDGF-BB was significantly higher in esophageal cancer patients than controls (3.76 vs. 2.66 μg/l, p = 0.0001) and corresponded with the disease advancement. Of evaluated clinicopathological features, lymph node metastases and distant metastases were independently associated with an increase in sPDGF-BB; however, only the association with lymph node metastases persist adjustment to platelets. In univariate analysis, sPDGF positively correlated with platelets (r=0.70, p < 0.0001), vascular endothelial growth factor (VEGF)-A (r=0.50, p < 0.0001), VEGF-C (r=0.57, p < 0.0001), white blood cells (r=0.32, p = 0.004), C-reactive protein (r=0.34, p = 0.004), IL-6 (r=0.35, p = 0.003), and IL-8 (r=0.45, p < 0.0001). In multivariate analysis, VEGF-C and platelets were independently associated with sPDGF-BB explaining 61% in its variability. With >2.845 μg/l cut-off, over 76% of patients had elevated sPDGF-BB. Its accuracy as lymph node metastases marker was 75%, sensitivity and specificity corresponding with >3.029 μg/l cut-off were 84 and 61%, respectively.

CONCLUSIONS

sPDGF-BB owns potential as a possible lymph node metastases marker and might be considered as a diagnostic tool in preliminary evaluation of esophageal cancer patients identifying those likely to be burdened with lymph node metastases, the disease recurrence monitoring, and/or preselecting patients for PDGF-directed cancer therapies.

The role of complement activity in the sensitivity of Salmonella O48 strains with sialic acid-containing lipopolysaccharides to the bactericidal action of normal bovine serum

Sialic acids are important constituents of animal tissue glycoconjugates and are also present in the antigens of some bacterial strains. Capsular polysaccharides with sialic acid (NeuAc) have been extensively studied with regard to sensitivity to the bactericidal action of serum, whereas little is known in this regard about lipopolysaccharides (LPS) which contain NeuAc. Strains of Salmonella O48, able to infect animals and containing the same structures of LPS with NeuAc, were examined for their susceptibility to the bactericidal action of normal bovine serum (NBS). The strains showed varied sensitivity to the bactericidal action of NBS, which indicates that the expression of LPS containing NeuAc residues is not critical for the strains' resistance to the serum's activity. In this study the mechanisms of complement activation responsible for killing serum-sensitive Salmonella O48 rods by NBS were also established. Three such mechanisms were distinguished: activation of the classical/lectin pathways, important (decisive) in the bactericidal mechanism of complement activation, parallel activation of the classical/lectin and alternative pathways, and independent activation of the classical and lectin or the alternative pathway.

The influence of strain, sex and age on selected biochemical parameters in blood serum of Buffalo and Wistar rats

The objective of the study was to determine interval values of biochemical parameters in the most commonly applied experimental model among different species, i.e. rats. Blood analysis of experimental animals is done in different research fields. They are important especially in experiments in pharmacology, pathophysiology, experimental surgery, toxicology and for monitoring experimental disorders in laboratory animals. In this paper, basic biochemical markers in the blood serum of Buffalo and Wistar rats are also compared in relation to the animals' age and sex. The values were obtained using the latest available measurement methods and the above-listed checkpoints were considered. The biochemical markers show variability between the particular groups of animals related to their age, sex, and strain. The obtained data may be used to create a model of interval values of biochemical parameters for the Buffalo and Wistar rat strains. This study is necessary to enhance our understanding on basic parameters in these animals which are often used in different medical experiments.

Photo-oxidative action in cervix carcinoma cells induced by HPD - mediated photodynamic therapy

Photodynamic therapy leads to oxidative stress through the generation of free radicals. Oxidative stress causes damage to cellular macromolecules such as nucleic acids, proteins and lipids.

AIM

To examine the hematoporphyrin derivative (HpD) - mediated photodynamic effect on cervical adenocarcinoma cell line HeLa.

METHODS

The HpD localization in HeLa cells was analyzed by confocal microscopy with epi-fluorescence system. Lipid peroxidation (LPO) was estimated by measurement of the concentration of malondialdehyde, protein degradation - by modified Ellman's method, superoxide dysmutase (SOD) - using Ransod Kit. The expression of inducible nitric oxide synthase (iNOS) was detected by immunocytochemical staining.

RESULTS

The HpD was distributed all over the cytoplasm with preferential localization in the inner side of the plasma membrane and around the nuclear envelope. The process of photosensitizer distribution was time dependent. PDT-HpD increased the level of malonodialdehyde (MDA), SOD activity and the expression of iNOS in HeLa cells. However, PDT induced the decrease in the level of protein-associated thiol groups.

CONCLUSIONS

Our study showed the important role of PDT-mediated oxidative stress in HeLa cells. HpD-PDT might be alternative and less invasive approach for treatment of patients with cervical cancer resistant for standard chemotherapy and radiotherapy.

Intermittent pneumatic compression in stable claudicants: effect on hemostasis and endothelial function

AIM

Intermittent pneumatic compression (IPC) increases systemic fibrinolytic activity but may also injure endothelial cells and thereby induce coagulation. The safety and utility of IPC in patients with peripheral arterial disease (PAD) therefore remains uncertain. The aim of this study was to determine whether IPC is associated with coagulation activation and endothelial cell damage, platelet factor 4 (PF4), thrombin-antithrombin complex (TAT), total nitrate and nitrite level and von Willebrand factor (VWF) concentration.

METHODS

PF4, TAT, total nitrate, nitrite level and VWF were analyzed before and after first, 5th, 15th session (1 hour/day) of IPC and then 3 weeks after completion of therapy in 25 claudicants and compared to 11 healthy volunteers of similar age and sex.

RESULTS

PF4, a measure of platelet activation/secretion, was significantly higher in claudicants (55+/-50 IU/mL) compared to healthy controls (22+/-14 IU/mL) (P<0.05). In PAD patients PF4 has decreased steadily and significantly throughout the time of compressive therapy (to 33+/-42 IU/mL) and further more at the end of the follow-up period (23+/-26 IU/mL). TAT concentration was low in PAD patients but further decreased during IPC therapy. There was a tendency of nitrite and nitrate concentration to increase during the course of IPC therapy, but in PAD patients it did not reached statistical significance (P=0.2), while in healthy controls this increase was significant (up to 79+/-14 mmol/L, P<0.05) and persisted 3 weeks after completion of IPC (up to 82+/-7 mmol/L, P<0.05). VWF antigen concentration remained stable in claudicants during IPC therapy and 3 weeks later but significantly decreased during IPC therapy (after fifth and fifteenth IPC session, P=0.04) and stayed decreased 3 weeks after treatment termination in control group. Pain-free walking distance (PWD) had increased continuously during treatment period from 55+/-23 to 63+/-32 meters after fifth IPC treatment, to 81+/-43 (P<0.05) after the last session of therapy, and slightly decreased to 77+/-28 meters 3 weeks after completion of IPC.

CONCLUSIONS

IPC is safe for PAD patients, does not activate coagulation, but decreases platelet activation and improves endothelial health; this coincides with significant prolongation of walking distance.

Even a mild anemia is related to tumor aggressiveness mediated by angiogenic factors

Esophagogastric cancers have high recurrence rates with lymph nodes being a common pattern. Pre-treatment anemia has been reported an independent prognostic factor of treatment failure regardless of treatment strategy, particularly associated with poor locoregional control. A causative relationship between anemia - tumor hypoxia - tumor aggressiveness mediated by angiogenesis up-regulation is advocated, yet remains controversial.

AIM

To determine whether and how the pre-treatment anemia is associa-ted with various aspects of disease aggressiveness and to evaluate the possible involvement of angiogenesis mediators.

METHODS

In 111 esophagogastric cancer patients we investigated the association of pre-treatment hemoglobin concentration and anemia presence with cancer-related, patients-related features and laboratory parameters including angiogenic factors: vascular endothelial growth factors A and C, interleukin-8 and midkine. Serum levels of angiogenic factors were assessed with immunoenzymatic tests.

RESULTS

Histology, disease stage, regional metastasis and dissemination in general, malnutrition and angiogenesis represented by midkine were found to correlate with anemia presence and hemoglobin concentration, while tumor extension, patient's age and sex accounted only for anemia presence. A tendency towards hemoglobin correlation with VEGF-A and Il-8 was also observed. Midkine, tumor histology and malnutrition were found to exert an independent effect on pre-treatment hemoglobin concentration and anemia presence in esophagogastric cancer patients. Hemoglobin level of 12 g/dL was found an optimal cut-off value for discrimination between localized and disseminated cancers.

CONCLUSIONS

Even a mild pre-treatment anemia is associated with cancers metastasizing especially to regional lymph nodes, which seems to be mediated by some of studied angiogenic factors.

Respiratory insufficiency related to COPD accelerates systemic inflammation, under-nutrition, and angiogenesis in esophageal malignancies

A number of esophageal cancer patients suffer from respiratory insufficiency due to the coexistence of chronic obstructive pulmonary disease (COPD).

AIM

To test the hypothesis that COPD-related systemic hypoxemia may result in accelerated inflammation, malnutrition, and angiogenesis in esophageal cancer patients.

METHODS

Serum levels of C-reactive protein (CRP), albumin, transferrin, interleukin-1, interleukin-6, interleukin-8, TNF-alpha, platelet-derived growth factor (PDGF-BB), and midkine and patient BMI and weight-loss rate were determined and compared with blood oxygenation status (pO(2), SaO(2)) in 35 esophageal cancer patients and 42 controls.

RESULTS

The incidence of cachexia tended to be higher in patients with systemic hypoxemia (67% vs 40%, p = 0.169). Mean SaO(2) level was also significantly decreased in cachectic patients (90.3 vs 93.3%, p = 0.026) and pO(2) exhibited a similar trend (58.0 vs 63.4 mmHg, p = 0.120). Transferrin (234 vs 316 mg/dl, p = 0.005) and albumin (31.9 vs 37.1 mg/dl, p= 0.002) concentrations were reduced and CRP was elevated (129.9 vs 54.7 mg/l, p = 0.004) in hypoxemic patients and correlated with pO(2) (r = 0.47, p = 0.016; r= 0.48, p = 0.012; r = -0.37, p = 0.064) and SaO(2) (r = 0.52, p = 0.006; r = 0.53, p = 0.006; r = -0.40, p= 0.042). Interleukin-6 (9.97 vs 2.21 pg/ml, p = 0.005) and midkine (2101 vs 944 pg/ml, p < 0.001) were elevated and PDGF-BB was decreased (12.2 vs 17.3 pg x 10(-6)/PLT, p = 0.014) in hypoxemic compared with normoxemic patients. Interleukin-6 and midkine negatively correlated with pO(2) (r = -0.44, p = 0.016; r = -0.42, p = 0.011) and SaO(2) (r = -0.54, p = 0.003; r = -0.57, p < 0.0001) and PDGF-BB correlated positively (r = 0.53, p = 0.003; r = 0.44, p = 0.020). Interleukin-8 level was affected by pO(2) (r = -0.55, p = 0.015) and SaO(2) (r= -0.55, p = 0.018) only in hypoxemic patients.

CONCLUSIONS

COPD-related systemic hypoxemia negatively affects the status of esophageal cancer patients by accelerating inflammation, under-nutrition, and angiogenesis.

Impact of systemic hypoxemia on cancer aggressiveness and circulating vascular endothelial growth factors A and C in gastroesophageal cancer patients with chronic respiratory insufficiency

AIM

Due to the common etiologic factor, a considerable number of esophagogastric cancer patients suffer from respiratory insufficiency in course of chronic obstructive pulmonary disease, primary to cancer. Systemic hypoxemia may account for poor oxygenation of tumor tissue-a main driving force of tumor neoangiogenesis. We hypothesized that in cancer patients with respiratory insufficiency, systemic hypoxemia may be related to enhanced aggressiveness of cancer on one side and to the elevation of angiogenic factors on the other.

METHODS

The levels of vascular endothelial growth factors A and C were determined with immunoenzymatic methods in patients diagnosed with esophagogastric cancer with or without co-existing respiratory insufficiency in course of chronic obstructive pulmonary disease and in healthy controls. Blood gasometry and hemoglobin levels of cancer patients were related to cancer histology and TNM status, and to circulating vascular endothelial growth factors A and C.

RESULTS

Patients with systemic hypoxemia had higher incidence rates of locally advanced tumors. Partial oxygen pressure and blood oxygen saturation were significantly lowered in patients with T4 cancers as compared to less advanced ones. Circulating vascular endothelial growth factor A, but not C, was more elevated in esophagogastric cancer patients with co-existing respiratory insufficiency, as compared to those without respiratory insufficiency. Vascular endothelial growth factor A was also strongly related to the extension of primary tumor.

CONCLUSION

Our results show that systemic hypoxemia in esophagogastric cancer patients is associated with the extension of primary tumor and that this effect might be mediated by the up-regulation of circulating vascular endothelial growth factor A.

Structure and serological analysis of the Hafnia alvei 481-L O-specific polysaccharide containing phosphate in the backbone chain

The lipopolysaccharide was extracted from cells of Hafnia alvei 481-L bacterial strain and, after mild acid hydrolysis, the O-specific polysaccharide was isolated and characterised. On the basis of chemical analyses and NMR spectroscopic studies of the polysaccharide and oligosaccharides obtained after Smith degradation, or hydrogen fluoride treatment, it was found that the repeating unit of the O-specific polysaccharide is a phosphorylated hexasaccharide: [see text]. The biological repeating unit of the H. alvei 481-L O-antigen has galactose phosphate at the nonreducing terminus. Serological tests indicate that this strain represents an individual serotype in the H. alvei genus.

Determination of endotoxin by the measurement of the acetylated methyl glycoside derivative of Kdo with gas–liquid chromatography-mass spectrometry

A gas-liquid chromatographic-mass spectrometric (GLC-MS) method was applied to the detection of 3-deoxy-d-manno-2-octulosonic acid (Kdo), a constituent of bacterial lipopolysaccharide (LPS, endotoxin). Samples containing LPS were dried, methanolyzed with 2 M HCl in methanol at 60 degrees C for 1 h and acetylated with acetic anhydride and pyridine (1:1, v/v) solution at 100 degrees C for 30 min, then the products were analyzed by GLC-MS or GLC-MSMS. Four acetylated methylglycoside methyl ester derivatives of Kdo are formed in these conditions, namely one with pyranose ring (Kdo1), two derivatives in the furanose form (Kdo2 and 3) and one derivative of anhydro Kdo (Kdo4), as results from their mass fragmentation patterns. Synthetic Kdo produced mainly Kdo4 derivative, whereas Kdo1 of pyranose ring shape was the predominating derivative formed from LPS. The ion fragment of m/z 375 was selected for the specific detection of this Kdo1 derivative, which might be applied for the endotoxin determination. That approach was used for the analysis of preparations of bacteria, bacteriophages and samples of animal sera. In order to ensure the removal of phosphate substitutions from Kdo, methanolyzed samples can be treated with alkaline phosphatase (2.6 U, pH 9.2, 37 degrees C, 15 min), what was elaborated on Vibrio LPS preparation.

[Isolation and comparative analysis of glycolipid fractions in bifidobacteria]

A comparative TLC analysis of lipid extracts from Bifidobacterium longum B 379 M, B. bifidum 791, and B. adolescentis 94 BIM has been performed. It is demonstrated that carbohydrate-containing lipid components were present in the bacteria, which differed in their chromatographic mobility (Rf) from similar compounds isolated from actinomycetes Stomatococcus mucilaginosus PCM 2415T, Nocardiopsis dassonvillei PCM 2492, Propionibacterium propionicum PCM 2431, Saccharopolyspora hirsuta PCM 2279 (= ATCC 27875T), Rhodococcus equi PCMT 559 (= ATCC 3969), and Gordonia bronchialis PCM 2167. Polar lipids of bifidobacteria exhibited the closest similarity to their counterparts from propionic acid bacteria. Preparative chromatography (silica gel column I; elution with chloroform, acetone, and methanol) of the lipid extract of B. adolescentis 94 BIM made it possible to isolate fractions containing nonpolar lipids, glycolipids, and phospholipids. Further purification of the glycolipid fraction (column II; eluant, methanol gradient in chloroform) produced preparations of glycolipids and phospholipids. The preparations were studied by two-dimensional TLC using solvent systems chloroform-methanol-H2O MiLi Q (65 : 25 : 4, v/v/v) and n-butanol-acetic acid-H2O MiLi Q (60 : 20 : 20, v/v/v) for directions I and II, respectively. Two major glycolipids were revealed (G1 and G2), in addition to compounds characteristic of the polar lipid group and minor glycolipids (g), the latter being present in considerably lesser amounts.

[Biological activity of polar lipids from bifidobacteria]

Fractions of polar lipids have been isolated from bifidobacteria, and the immunoreactivity and serological specificity of glycolipids and phospholipids have been studied. Enzyme immunoassay (dot-EIA) of polar lipids demonstrates that the fractions of glycolipids and phospholipids of bifidobacteria are highly immunoreactive. Pronounced reactions of major glycolipids and phospholipids with a homologous polyvalent antiserum against B. adolescentis 94-BIM have been observed at antigen concentrations of approximately 100 ng. The antiserum contained high titers of specific antibodies against glycolipids and phospholipids of bifidobacteria, as demonstrated by heterogeneous solid-phase enzyme immunoassay (ELISA). Experimental data confirming the presence of subpopulations of specific antibodies (antiglycolipid and antiphospholipid) in the blood sera of immunized animals lead to the conclusion that the major glycolipids and phospholipids of bifidobacteria are specific markers appropriate for serological diagnostics.

[Nocardia and human nocardiosis]

Nocardia spp. are pathogens commonly found in soil worldwide, and they cause mostly opportunistic infections in humans and animals, complicating both immunodepressive states and primary diseases. Nocardiosis is difficult to proper microbiological and clinical diagnosis because of its non-specific symptoms, which manifest as the cutaneous and sub-cutaneous infections, lung symptoms and the dissemination through the bloodstream to other organs. General characteristics of Nocardia, human nocardiosis as well as the microbiological diagnostics routine and treatment are discussed.

[Analysis of fatty acids from lipopolysaccharides of Bacteroides thetaiotaomicron and Bacteroides fragilis]

The aim of this study was to determine and to compare fatty acids occurring in lipopolysaccharides (LPS) isolated from B. thetaiotaomicron and B. fragilis strains of different origin. Lipopolysaccharides of three B. thetaiotaomicron strains and four B. fragilis strains were isolated by phenol-water extraction according to the procedure of Westphal and Jann (1965). Water-phase LPS fractions were then treated with nucleases and purified by ultracentrifugation as described by Gmeiner (1975). Fatty acid methyl esters, obtained by methanolysis of LPS, were analysed in gas-liquid chromatography combined with mass spectrometry (GLC-MS). Trimethylsilylated hydroxyl groups of fatty acid methyl esters were identified with GLC-MS using a method of selective ion monitoring (SIM). Lipopolysaccharides of B. thetaiotaomicron and B. fragilis strains contained long-chain (15-18 carbon atoms) fatty acids. The broad spectrum of simple long-chain and branched-chain fatty acids as well as 3-hydroxy fatty acids were detected. The main fatty acid of analyzed bacterial species was 3-hydroxy-hexadecanoic acid (3OH C16:0). Several 3-hydroxy fatty acids were detected in LPS of examined strains. Fatty acids occurring in LPS of B. thetaiotaomicron and B. fragilis strains appeared to be qualitatively similar. Quantitative differences in fatty acids composition of lipopolysaccharides isolated from strains of different origin were observed.

Bactericidal activity of normal cord serum (NCS) against Gram-negative rods with sialic acid-containing lipopolysaccharides (LPS)

Sialic acids, that are important constituents of animal tissue glycoconjugates, are also present in antigens of some bacterial strains. Capsular polysaccharides with sialic acid have been extensively studied whereas little is known on lipopolysaccharides which contain sialic acid. The susceptibility of Gram-negative strains with sialic acid-containing lipopolysaccharides to the bactericidal action of the sera of newborns was examined. The strains investigated showed variable sensitivity to the bactericidal action of normal cord serum.

[Molecular mimicry of bacterial polysaccharides and their role in etiology of infectious and autoimmune diseases]

Molecular mimicry is one of the most important pathogenic factor of microorganism and is defined as a structural similarity of microbial molecules to host tissue contributing to the pathogenicity. Mimicry can be observed at the molecular, serological and functional level. In the review the infectious diseases have been discussed where the mimicry phenomenon may occur, and also autoimmune disease where due to the molecular mimicry bacterial structures are potent to induce adverse immune reactions. The cross-reacting molecules mimicking the host structures comprise colominic acid, sialic acid containing capsular polysaccharides of Streptococcus group B, phosphocholine containing antigen, lipopolysaccharides of Campylobacter jejuni contributing in induction of Guillain-Barré syndrome or Lewis antigen containing lipopolysaccharides of Helicobacter pylori inducing gut carcinoma. Knowledge on the phenomenon of molecular mimicry is important when new conjugate vaccine has to be constructed, because great care should be paid not to induce autoantibodies with synthetic immunogen. Investigation of microbial factors reveal that many autoimmune diseases are of infection etiology.

[Fimbriae as a pathologic factor of bacteria and a carrier in conjugate vaccines]

Fimbriae play important role as pathogenic factors in many bacteria by their adhesive properties. Adhesin is located at the tip of fimbriae but also in other parts of fimbriae. Recent findings on structure of fimbriae genes and their expression for the biosynthesis and formulation of complete fimbriae have been described. Special attention was focused on the participation of fimbriae in the mechanism of pathogenesis and their specificity towards tissue receptors. Most recent studies have been performed on E. coli and Klebsiella and those data predominate in this work. Fimbriae can be used for the construction of vaccine as a proteinous carrier for haptenic carbohydrate epitopes. In conjugates fimbriae express distinct immunogenic, adjuvant and protective properties.

Structure of the O-specific polysaccharide isolated from the lipopolysaccharide of Citrobacter gillenii serotype O12a, 12b strain PCM 1544

A neutral O-specific polysaccharide was isolated from the lipopolysaccharide of Citrobacter gillenii strain PCM 1544, representing serotype O12a,12b. The polysaccharide was studied by sugar and methylation analyses and Smith degradation along with 1H and 13C NMR spectroscopy, including a ROESY experiment. The following structure of the tetrasaccharide repeating unit was established, in which substitution with terminal GlcNAc is approximately 60%. [structure: see text]

Structural and serological studies on Hafnia alvei O-specific polysaccharide of alpha-D-mannan type isolated from the lipopolysaccharide of strain PCM 1223

On the basis of chemical and methylation analyses, one- and two-dimensional (1)H- and (13)C-NMR spectroscopy, including COSY, TOCSY, NOESY and (1)H, (13)C HSQC experiments, a neutral O-specific polysaccharide isolated from Hafnia alvei strain PCM 1223 lipopolysaccharide (LPS) was found to be an alpha-mannan composed of pentasaccharide repeating units having the following structure:-->3)-alpha-D-Manp-(1-->3)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->. Immunoblotting showed a strong cross-reactivity between anti-H. alvei PCM 1223 serum and LPSs of Escherichia coli O9 and Klebsiella pneumoniae O3. The serological relationship of the LPSs of these bacteria is due to the structural identity of their O-specific polysaccharides, though the LPSs differ in their core regions.

Structure of the O-specific polysaccharide of Hafnia alvei PCM 1196

An acidic O-specific polysaccharide was isolated from Hafnia alvei PCM 1196 lipopolysaccharide and studied by sugar and methylation analyses along with one- and two-dimensional 1H and 13C NMR spectroscopy, including NOESY and HMBC experiments. The following structure of the pentasaccharide repeating unit was established: -->4)-alpha-D-GalpA-(1-->3)-beta-D-GlcpNAc-(1-->2)-beta-D-Galp-(1-->6)-alpha-D-Glcp-(1-->6)-alpha-D-GlcpNAc-(1-->.

Structure of the lipopolysaccharide core region of Hafnia alvei strains 1185 and 1204

Sugar and methylation analyses using gas chromatography/mass spectrometry and NMR spectroscopy proved that the core oligosaccharides of Hafnia alvei strains 1185 and 1204 have the following formula: carbohydrate sequence [see text] where Kdo = 3-deoxy-oct-2-ulosonic acid and P-PEtN = diphosphorylethanolamine. The structure shown above is a slight modification of the typical core region of H. alvei lipopolysaccharides. The difference refers to one sugar only: terminal galactose is present in the core of strains of 1185 and 1204, while terminal glucose in the typical core.

Effect of sepsis and cardiac surgery with cardiopulmonary bypass on plasma level of nitric oxide metabolites, neopterin, and procalcitonin: correlation with mortality and postoperative complications

OBJECTIVES

To examine the hypothesis that nitrite/nitrate, neopterin, and procalcitonin (PCT) levels can be useful predictors of sepsis-associated mortality and predictors of the postoperative complications after cardiopulmonary bypass (CPB).

DESIGN

Prospective clinical study.

SETTING

Intensive care unit of the Medical University Hospital.

PATIENTS

41 patients with sepsis, 42 patients subjected to open heart surgery with CPB, and 30 healthy volunteers.

MEASUREMENTS AND RESULTS

Nitrite/nitrate, neopterin, and PCT levels were measured in septic patients as soon as sepsis was recognized and then on the 2nd, 3rd, and 5th days of treatment. Statistically significant differences between survivors and nonsurvivors were found for neopterin and PCT. The area under receiver operating characteristic curve (AUC) for both parameters as predictors of mortality was above 0.8. The nitrite/nitrate level was also higher in nonsurvivors, but the AUC remained below 0.8, which indicates poor predictive power. The same parameters were measured in patients undergoing cardiac surgery before, during and after CPB establishment. The development of post-operative complications was correlated with increased postoperative neopterin and PCT levels. Additionally, neopterin was found as an early marker for the prognosis of postoperative complications, since patients who developed organ dysfunction had had elevated concentration of this parameter even before surgery (AUC 0.83). Measurement of NO metabolite levels was less specific and less sensitive.

CONCLUSIONS

Our results confirm the value of PCT and neopterin measurement as diagnostic tools in monitoring the clinical course of patients in intensive care units.

Structure of the sialic acid-containing O-specific polysaccharide from Salmonella enterica serovar Toucra O48 lipopolysaccharide

Lipopolysaccharide was extracted from cells of Salmonella enterica serovar Toucra O48 and, after mild acid hydrolysis (1% AcOH, 1 h, 100 degrees C or 0.1 M NaOH-AcOH, pH 4.5, 5 h, 100 degrees C), the O-specific polysaccharide was isolated and characterized. The core and an oligosaccharide containing a fragment of the repeating unit linked to the core region were also obtained, depending on hydrolysis conditions. On the basis of sugar and methylation analyses and NMR spectroscopy of the hydrolysis products, the biological repeating unit of the O-specific polysaccharide was shown to be the following trisaccharide: -->4)-alpha-Neup5Ac(2-->3)-L-alpha-FucpNAc(1-->3)-D-beta-Glc pNAc(1--> The polysaccharide O-chain was substituted with a single molar equivalent of O-acetyl group, distributed between the Neu5Ac O-9 and O-7 positions, in an approximate ratio of 7 : 3.

Antigenic properties of LPS extracted from Bacteroides fragilis enterotoxin producing strains

Antigenic properties of enterotoxigenic Bacteroides fragilis (ETBF) strains isolated in Poland were compared with reference strains. The agglutination and passive hemagglutination, SDS-PAGE analysis and immunoblotting tests as well as analyses of sugars and fatty acids were performed with lipopolysaccharide (LPS) preparations obtained from water-phase of phenol-water extracts. Some differences in serological reactivity between ETBF antigens were observed. The antigen of the NTBF (nonenterotoxigenic) reference strain IPL E-323 expressed weak cross-reactivity with sera against whole cells of ETBF strains in serological tests. There were some differences observed between ETBF and NTBF strains in fatty acids and sugar composition. The LPS preparations probably possess a common core structure and the O-specific polysaccharides of variable chain length.

Structural heterogeneity of the sialic-acid-containing oligosaccharides from the lipopolysaccharide of Hafnia alvei strain 2 as detected by FABMS studies

The structure of four oligosaccharide fractions from the Hafnia alvei strain 2 lipopolysaccharide (LPS) have been assigned by FABMS. This approach corroborates data previously established by NMR spectroscopy for the major oligosaccharides in these fractions [A. Gamian, E. Romanowska, U. Dabrowski, J. Dabrowski, Biochemistry 30 (1991) 5032-5038; E. Katzenellenbogen, A. Gamian, E. Romanowska, U. Dabrowski, J. Dabrowski, Biochem. Biophys. Res. Commun. 194 (1993) 1058-1064; N. Ravenscroft, A. Gamian, E. Romanowska, Eur. J. Biochem. 227 (1995) 889-896]. In addition, the MS/MS with B/E linked scan technique allowed the detection of an additional oligosaccharide with the structure: [formula: see text] lacking the branched O-6 linked glucopyranose residue at the 3-linked Gal unit, which indicates a structural heterogeneity for the major oligosaccharide fraction.

Immunochemical studies of the lipopolysaccharide O-specific polysaccharide of Hafnia alvei PCM 1199 related to H. alvei PCM 1205

On the basis of chemical analyses and NMR spectroscopic studies, it was found that the O-specific polysaccharide (O-PS) isolated from the Hafnia alvei PCM 1199 lipopolysaccharide (LPS) is a glycerol teichoic-acid-like polymer having a repeating unit of the following structure: [structure in text] where Qui4NAc is 4-acetamido-4,6-dideoxyglucose and O-acetylation at both positions is non-stoichiometric. The glycosidic linkage of the lateral beta-D-GlcpNAc residue is acid-labile and cleaved from the O-PS during mild acid hydrolysis or dephosphorylation with 48% hydrofluoric acid. Comparative analysis revealed that the structure of the H. alvei PCM 1199 O-PS is similar to that of H. alvei PCM 1205, which differs in the presence of an additional lateral alpha-D-Glcp residue and the position of one of the O-acetyl groups only. Accordingly, serological tests revealed a high degree of serological similarity between LPSs and O-PSs of the two H. alvei strains.

Reinvestigation of the O-specific polysaccharides of Hafnia alvei lipopolysaccharides isolated from strains ATCC 13337 and 1187

The structure of the O-specific polysaccharides of the lipopolysaccharides produced by Hafnia alvei strains ATCC 13337 and 1187 was reinvestigated. The position of phosphate group in the repeating units of the polysaccharides was established with the aid of 1H detected, 31P edited NMR spectra. According to the results obtained, the polysaccharides are teichoic acid-like polymers with the repeating units of the following structure: [formula: see text] where Acyl = D-3-hydroxylbutyryl, and 3-O-acetylation was approximately 30%.

Immunochemical characterization of lipopolysaccharide from glucose-nonfermenting gram-negative clinical bacterial isolate

A glucose-nonfermenting Gram-negative bacterial strain isolated from bronchofiberoscope used for examination of the patients suffering from pulmonary diseases was subjected to phenol-water extraction. Lipopolysaccharides (LPS) isolated from the water and the phenol phase differed in fatty acid composition. Both contained xylose, glucose, glucosamine and components typical for LPS, namely heptose, 3-deoxyoctulosonic acid (Kdo) and 3-hydroxymyristic acid. The presence of sphingosine in all LPS preparations classifies the strain to the genus Sphingomonas.

Immunochemical characterization of lipopolysaccharide from glucose-nonfermenting gram-negative clinical bacterial isolate

A glucose-nonfermenting Gram-negative bacterial strain isolated from bronchofiberoscope used for examination of the patients suffering from pulmonary diseases was subjected to phenol-water extraction. Lipopolysaccharides (LPS) isolated from the water and the phenol phase differed in fatty acid composition. Both contained xylose, glucose, glucosamine and components typical for LPS, namely heptose, 3-deoxyoctulosonic acid (Kdo) and 3-hydroxymyristic acid. The presence of sphingosine in all LPS preparations classifies the strain to the genus Sphingomonas.

Structural studies of the major glycolipid from Saccharopolyspora genus

A major glycolipid was isolated from the well characterized Saccharopolyspora species, S. hirsuta, S. rectivirgula, S. erythraea and one not completely identified strain (Saccharopolyspora sp.). On the basis of sugar and methylation analysis, specific enzymatic and chemical degradations of the carbohydrate moiety, its FAB mass spectrometry and NMR spectroscopy characterizations, the carbohydrate part was shown to be the glycerol linked dimannoside alpha-D-Manp-(1-->3)-alpha-D-Manp-(1-->1/3)Gro. The internal mannose residue is esterified at C-6 by one fatty acid residue, whereas another fatty acyl chain substitutes the primary methylene position of glycerol. The main fatty acyl residues are anteiso-branched heptadecanoic acid and the iso-branched fatty acids iso-17:0, iso-16:0, and iso-18:0, with the former species being predominant. The major glycolipid has potential value for taxonomic and diagnostic purposes, especially in the specific diagnosis of farmer's lung disease.

Structural study and serological characterisation of the O-specific polysaccharide of Hafnia alvei PCM 1185, another Hafnia O-antigen that contains 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]-D-glucose

The O-specific polysaccharide of H. alvei strain PCM 1185 contains D-glucose, D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose, and 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]-D-glucose (Qui3NAcyl) in the ratios 2:1:1:1 as well as O-acetyl groups. On the basis of sugar and methylation analyses of the polysaccharide before and after chemical modifications (O-deacetylation, carboxyl reduction, Smith degradation), as well as 1H and 13C NMR spectroscopy, including 1D sequential, selective spin-decoupling, 2D homonuclear and 13C,1H heteronuclear correlation spectroscopy (COSY), and 2D rotating-frame NOE spectroscopy, it was found that the polysaccharide has a pentasaccharide repeating unit with the following structure: [formula: see text] with O-acetyl groups present in nonstoichiometric amounts, mainly at position 2 of GlcA and position 6 of GlcNAc or lateral Glc. Serological study showed that H. alvei strain PCM 1185 can be placed in a new serotype D and that an O-acetyl group can be a part of its epitope.

The occurrence of glycine in bacterial lipopolysaccharides

The aminoacyl analysis of endotoxic lipopolysaccharides (LPS) isolated from several bacteria revealed essential amounts of glycine, among the inherent LPS components. Significant amounts of the glycine was detected in lipopolysaccharides isolated from over 30 strains of Escherichia, Salmonella, Hafnia, Citrobacter and Shigella species. Glycine as a single amino acid was found only in a core part of LPS. Molar ratio of glycine in core oligosaccharide fraction ranged from 0.2 to 0.6 per 3 heptoses. The oligosaccharide enriched in glycine was isolated using the HPLC. The amino acid appeared to be terminally located in a core oligosaccharide. The labelling of the lipopolysaccharide cores was achieved when the bacteria were cultivated in the presence of radioactive [14C]glycine. The labelled core oligosaccharide released the radioactivity during treatment with mild alkali or acid (0.1 M NaOH or HCl, 100 degrees C, 4 h). The radioactivity in SDS-polyacrylamide gel electrophoresis migrated exclusively with LPS. The results indicate that amino acid is an integral constituent of core oligosaccharide in lipopolysaccharide.

[Studies of a glycyl component of lipopolysaccharides]

The aminoacyl analysis of endotoxic lipopolysaccharides (LPS) isolated from several bacteria revealed essential amounts of glycine, among the inherent LPS components. Glycine as a single amino acid was found only in a core part of LPS. The results indicate that amino acid is an integral constituent of core oligosaccharide in lipopolysaccharide.

The sensitivity of Hafnia alvei strains to the bactericidal effect of serum

Most Hafnia alvei strains are sensitive to the bactericidal action of normal bovine serum (NBS) as well as to a serum in which the alternative pathway of complement activation has been thermally blocked. Introduction of polysaccharides (PS) to NBS lowers the bactericidal effect. In a serum in which the alternative pathway of complement activation is blocked, PS completely cancels the bacterial effect.

Selective spectrophotometric determination of glucose and fructose in the presence of aldoses using phenol-acetone reagent and cerium(III) chloride

Aqueous mixtures of glucose and fructose produce red solutions when treated with 2% (w/v) phenol in 5% (v/v) aqueous acetone in the presence of concentrated sulfuric acid. The color is stable for days, and the red chromophore has an absorbance maximum at 568 nm. When the concentration of phenol is raised to 25%, fructose, but not glucose, produces red solutions, allowing for the selective detection of ketoses. Two complementary methods have been developed to remove the interference of ketoses in solutions containing glucose. The first one relies on the selective reduction of ketoses with sodium borohydride in the presence of cerium(III) chloride prior to the addition of the phenol-acetone reagents. The second method is based on the differential specific determination of glucose using 2% versus 25% levels of phenol. The relative sensitivities of different sugars are also presented as well as the applicability of the methods using bacterial polysaccharides for immunochemical analyses. The quantitative determination of glucose or ketoses in the polysaccharides does not require hydrolysis prior to the estimation.

[Structural and serologic characteristics of O-specific polysaccharides of Hafnia alvei PCM 1185 and 1199]

This work describes results of studies of O-specific oligosaccharide repeating units from lipopolysaccharides of two related Hafnia alvei serotypes. The linkage between O-antigen and the core region in PCM 1199 LPS has been also established. The O-acetyl residues present in the polysaccharides are involved in formation of epitopes.