bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of Microbial Growth on the Surface of Materials in Contact with Water Intended for Human Consumption Using ATP Method
Authors: SZCZOTKO MACIEJ , KROGULSKI ADAM
Published: November 2019

Elaboration of an assessment method for plumbing materials contacting drinking water was the main purpose of this study. The investigation was conducted in 8 week cycles in dynamic conditions using a continuous flow reactor. Microbial growth was measured indirectly by a bioluminescence technique (ATP assay). Every week swabs from the surface of tested materials (polypropylene and different types of polyethylene), from the domestic market were collected and the level of bioluminescence was examined. The results obtained from the surface of tested materials were repeatable and clearly approximated those obtained from the surface of a negative control (stainless steel, low susceptibility for microbial growth). The level of bioluminescence (ATP) on the surface of positive control (paraffin, high susceptibility for microbial growth) was many times higher than that observed on other materials. The presented investigation was the main part of a validation process, which in short time will serve to initiate a complete assessment system for organic materials contacting drinking water.
Biodeterioration of Optical Glass Induced by Lubricants Used in Optical Instruments Technology
Authors: BARTOSIK MAGDALENA , ŻAKOWSKA ZOFIA , CEDZIŃSKA KRYSTYNA , ROŻNIAKOWSKI KAZIMIERZ
Published: November 2019

The process of biodeterioration of optical glass was studied after being induced by an auxiliary material (lubricant 4CKP) used in the production of optical instruments. It was determined that the lubricant can initiate growth of conidia of Aspergillus niger fungus. Acid spawn metabolites cause deterioration of the glass surface. Measurements of laser light beam transmittance through the glass plate and the AAS chemical analysis method of the post-culture fluid allowed to determine that glass with a high SiO2 content is most resistant to corrosion caused by the growth of A. niger fungi spawn.
Toxoplasma gondii: Usefulness of ROP 1 Recombinant Antigen in an Immunoglobulin G Avidity Assay for Diagnosis of Acute Toxoplasmosis in Humans
Authors: HOLEC-GĄSIOR LUCYNA , DRAPAŁA DOROTA , LAUTENBACH DARIUSZ , KUR JÓZEF
Published: November 2019

The results present in this study suggest that the Toxoplasma gondii recombinant ROP1 antigen in an IgG avidity test can be useful for detection of acute stage of infection. Specific antibodies of low avidity were detected in most of the sera from individuals with acute toxoplasmosis, while the absence or specific antibodies of high avidity were detected in sera from patients with chronic infection.
Comparison of Different PCR Methods for Detection of Brucella spp. in Human Blood Samples
Authors: AL-AJLAN HISHAM H. , IBRAHIM ABDELNASSER S.S. , AL-SALAMAH ALI A.
Published: November 2019

For detection of Brucella species by PCR four DNA extraction methods and four targets were compared using pure culture of Brucella melitensis and the best conditions were applied in clinical samples. It was found that the MagNA Pure LC method was the most efficient and sensitive method showing a positive PCR reaction with DNA extracted from as low as 25 and 100 CFU suspended in one ml blood and one ml water, respectively. Detection of Brucella spp. by conventional PCR was investigated using four different targets. The results indicated that The B4-B5 amplification method was the most sensitive one as it could amplify DNA extracted from as a low as 25 and 100 CFU/ml suspended in one ml water and blood, respectively. Furthermore real-time PCR was able to detect Brucella using DNA extracted from as low as 50 CFU/ml blood and 15 CFU/ml water, respectively. The best and optimum detection conditions were applied to the clinical samples. Evaluation of conventional PCR assays on blood specimens confirmed 72% of the results obtained by conventional blood culture methods with a specificity of 95%, while serum samples had a sensitivity of 54% and specificity of 100%. Real-time PCR was generally found to be more sensitive and specific for detecting Brucella spp. in blood and serum samples compared to conventional PCR. The real-time PCR done on blood specimens confirmed 77.5% of the results obtained by conventional blood culture methods with specificity of 100%, while 60% of serum samples were found to be positive with specificity of 100%. These results suggest that serum and blood analysis by conventional and real time PCR is a convenient and safe method for rapid and accurate diagnosis of brucellosis.
Antibiofilm Activity of Selected Plant Essential Oils and their Major Components
Authors: BUDZYŃSKA ALEKSANDRA , WIĘCKOWSKA-SZAKIEL MARZENA , SADOWSKA BEATA , KALEMBA DANUTA , RÓŻALSKA BARBARA
Published: November 2019

The aim of the study was to examine the antibiofilm activity of selected essential oils (EO): Lavandula angustifblia (LEO), Melaleuca alternifolia (TTO), Melissa officinalis (MEO) and some of their major constituents: linalool, linalyl acetate, alpha-terpineol, terpinen-4-ol. Biofilms were formed by Staphylococcus aureus ATCC 29213 and Escherichia coli NCTC 8196 on the surface of medical biomaterials (urinary catheter, infusion tube and surgical mesh). TTC reduction assay was used for the evaluation of mature biofilm eradication from these surfaces. Moreover, time-dependent eradication ofbiofilms preformed in polystyrene 96-well culture microplates was examined and expressed as minimal biofilm eradication concentration (evaluated by MTT reduction assay). TTO, alpha-terpineol and terpinen-4-ol as well as MEO, showed stronger anti-biofilm activity than LEO and linalool or linalyl acetate. Among the biomaterials tested, surgical mesh was the surface most prone to persistent colonization since biofilms formed on it, both by S. aureus and E. coli, were difficult to destroy. The killing rate studies of S. aureus biofilm treated with TTO, LEO, MEO and some of their constituents revealed that partial (50%) destruction of 24-h-old biofilms (MBEC50) was achieved by the concentration 4-8 x MIC after 1 h, whereas 2-4 x MIC was enough to obtain 90% reduction in biomass metabolic activity (MBEC90) after just 4 h of treatment. A similar dose-dependent effect was observed for E. coli biofilm which, however, was more susceptible to the action of phytochemicals than the biofilms of S. aureus. It is noteworthy that an evident decrease in biofilm cells metabolic activity does not always lead to their total destruction and eradication.
Selection and Adaptation of Saccharomyces cerevisae to Increased Ethanol Tolerance and Production
Authors: FIEDUREK JAN , SKOWRONEK MARCIN , GROMADA ANNA
Published: November 2019

A total of 24 yeast strains were tested for their capacity to produce ethanol, and of these, 8 were characterized by the best ethanol yields (73.11-8 1.78%). The most active mutant Saccharomyce s cerevisiae ER-A, resistant to ethanol stress, was characterized by high resistance to acidic (pH 1.0 and 2.0), oxidative (1 and 2% of H2O2), and high temperature (45 and 52 degrees C) stresses. During cultivation under all stress conditions, the mutants showed a considerably increased viability ranging widely from about 1.04 to 3.94-fold in comparison with the parent strain S. cerevisiae ER. At an initial sucrose concentration of 150 g/l in basal medium A containing yeast extract and mineral salts, at 300C and within 72 h, the most active strain, S. cerevisiae ER-A, reached an ethanol concentration of 80 g/1, ethanol productivity of 1.1 g/Il/h, and an ethanol yield (% of theoretical) of 99.13. Those values were significantly higher in comparison with parent strain (ethanol concentration 71 g/1 and productivity of 0,99 g/l/h). The present study seems to confirm the high effectiveness of selection of ethanol-resistant yeast strains by adaptation to high ethanol concentrations, for increased ethanol production.
Cytotoxicity of the Aspergillus Fungi Isolated from Hospital Environment
Authors: GNIADEK AGNIESZKA , MACURA ANNA B. , GÓRKIEWICZ MACIEJ
Published: November 2019

The majority of mycotoxins produced by Aspergillus fungi are immunosuppressive agents, and their cytotoxicity may impair defense mechanisms in humans. The objective of the study was evaluation of the cytotoxicity of fungi isolated from an environment where inpatients with impaired immunity were present. The materials comprised 57 fungal strains: Aspergillus fumigatus, Aspergillus niger: Aspergillus ochraceus, Aspergillus flavus, Aspergillus versicolor and Aspergillus ustus isolated from hospital rooms in Cracow. The cytotoxicity of all the strains was evaluated using the MTT test (3-(4,5-dimethylthiazol-2-yl) 2,5 diphenyltetrazolium bromide). To emphasize the differences in cytotoxicity among the particular strains, variance analysis (ANOVA) and Tukey's difference test were used. Out of 57 Aspergillus strains tested, 48 (84%) turned out to be cytotoxic. The cytyotoxicity was high (+++) in 21 strains, mainly in A. fumigatus. The least cytotoxic were A. niger fungi, this being statistically significant (p<0,05). To protect a patient from the adverse effects of mycotoxins, not only his or her immunity status should be evaluated but also the presence of fungi in hospital environment and their cytotoxicity should be monitored (possible exposure).
Production and Partial Characterization of High Molecular Weight Extracellular α-amylase from Thermoactinomyces vulgaris Isolated from Egyptian Soil
Authors: ABOU DOBARA M.I. , EL-SAYED A.K. , EL-FALLAL A.A. , OMAR N.F.
Published: November 2019

Optimizing production of alpha-amylase production by Thermoactinomyces vulgaris isolated from Egyptian soil was studied. The optimum incubation period, temperature and initial pH of medium for organism growth and enzyme yield were around 24 h, 55 degrees C and 7.0, respectively. Maximum alpha-amylase activity was observed in a medium containing starch as carbon source. The other tested carbohydrates (cellulose, glucose, galactose, xylose, arabinose, lactose and maltose) inhibited the enzyme production. Adding tryptone as a nitrogen source exhibited a maximum activity of alpha-amylase. Bactopeptone and yeast extract gave also high activity comparing to the other nitrogen sources (NH4CI, NH4NO3, NaNO3, KNO3, CH3CO2NH4). Electrophoresis profile of the produced two alpha-amylase isozymes indicated that the same pattern at about 135-145 kDa under different conditions. The optimum pH and temperature of the enzyme activity were 8.0 and 60 degrees C, respectively and enzyme was stable at 50 degrees C over 6 hours. The enzyme was significantly inhibited by the addition of metal ions (Na+, Co2+ and Ca2+) whereas CI- seemed to act as activator. The enzyme was not affected by 0.1 mM EDTA while higher concentration (10 mM EDTA) totally inactivated the enzyme.
Halomonas sp. nov., an EPA-Producing Mesophilic Marine Isolate from the Indian Ocean
Authors: SALUNKHE DIPTI , TIWARI NEHA , WALUJKAR SANDEEP , BHADEKAR RAMA
Published: November 2019

Marine samples from the Indian Ocean were used to isolate and characterize the organisms with respect to their fatty acid profiles. Six mesophilic isolates (MBRI 6, MBRI 8, MBRI 9, MBRI 10, MBRI 12 and MBRI 13) were obtained from three different water samples. They were i) Gram-negative, ii) catalase positive, iii) produced acid from glucose and maltose, iv) tolerated 5 to 15% NaCI v) except MBRI 9, showed pH tolerance in the range of 5.0 to 9.0 with optimum pH 7.0 to 8.0 v) grew well at 30 degrees C and were able to grow in the range of 15 to 45 degrees C. EPA, an essential omega-3 fatty acid, was produced by these isolates in the range of 12 to 60% at 30 degrees C. MBRI 12 was found to be a potential source as it produced 60% EPA. This isolate was further identified by partial 16S rDNA sequencing and phylogenetic analysis revealed that the strain belonged to Gammaproteobacteria and was closely related to Halomonas bolviensis (96% sequence similarity, 570 bp). Thus a new genus of Halomonas may be included in earlier reported EPA- producing prokaryotic genera affiliated to the Gammaproteobacteria.
Yersinia Species in the Dunnock (Prunella modularis) in Sub-alpine Habitats of the Western Carpathians
Authors: KISKOVÁ JANA , HREHOVÁ ZUZANA , JANIGA MARIÁN , LUKÁŇ MARTIN , HAAS MARTINA , JURČOVIČOVÁ MARTINA JURČOVIČOVÁ
Published: November 2019

The study presents the prevalence of Yersinia species in dunnok Prunella modularis from the sub-alpine zone of the Western Carpathians. Bacteria were detected from cloacal and pharyngeal swabs from 97 specimens using PCR assay. Yersinia enterocolitica showed the highest prevalence (47.4%) from among the determined Yersinia species. Yersinia species (except Y frederiksenii) were detected more frequently in pharyngeal than cloacal samples. The highest prevalence of yersiniosis was detected in April (Yersinia spp. - 80%, Y. enterocolitica - 70%). No statistically differences were observed in the prevalence of Yersinia spp. between males and females and between juveniles and adult birds. Bacterial contamination did not affect body weight or tarsus length.
First Report of Serratia plymuthica Causing Onion Bulb Rot in Poland
Authors: KOWALSKA BEATA , SMOLIŃSKA URSZULA , OSKIERA MICHAŁ
Published: November 2019

Specific bacterial disease symptoms were observed on onion bulbs in almost all regions in Poland. For the purpose of identification of agents causing disease, bacteria were isolated from the symptomatic plants. Their pathogenicity was confirmed by using pathogenicity test on onion scales. These bacteria were identified biochemically and molecularly as Serratia plymuthica.
Immobilized Cells of Recombinant Escherichia coli Strain for Continuous Production of L-aspartic Acid
Authors: SZYMAŃSKA GRAŻYNA , SOBIERAJSKI BOGUSŁAW , CHMIEL ALEKSANDER
Published: November 2019

For L-aspartic acid biosynthesis, high production cells of Escherichia coli mutant B-715 and P1 were immobilized in chitosan gel using a technique developed in our laboratory. The immobilization process reduced initial activity of the intact cells, however, the biocatalyst produced was very stabile for long-term use in multi-repeated batch or continuous processes. Temperature influence on the conversion of ammonium fumarate to L-aspartic acid was investigated. In long-term experiments, over 603 hours, the temperature 40 degrees C was found to be the best for both biocatalyst stability and high conversion rate. The optimum substrate concentration was 1.0 M. Continuous production of L-aspartic acid was investigated in three types of column bioreactors characterized by different volumes as well as different high to biocatalyst bed volume rations (Hz/Vz). The highest conversion rate, 99.8%, and the productivity 6 g/g/h (mass of L-aspartic acid per dry mass of cells in biocatalyst per time unit) was achieved in the bioreactor with the highest value Hz/Vz = 3.1, and liquid hour space velocity value of 5.2, defined as the volume of feeding substrate passed per volume of catalyst in bioreactor per one hour.
Efficacy of UV Treatment in the Management of Bacterial Adhesion on Hard Surfaces
Authors: KOLAPPAN A. , SATHEESH S.
Published: November 2019

The efficacy of UV treatment to control bacterial adhesion onto hard surfaces was investigated in laboratory conditions. The major characteristics necessary for biofilm formation like extracellular polymeric substance (EPS) production, carbohydrate and protein concentration in EPS, and adhesion ability onto hard surface were studied using two bacterial strains isolated from marine biofilms. The results showed that there was a considerable difference between the control and UV treated bacterial cultures in their viability, production of EPS, and adhesion ability. The protein and carbohydrate concentration of the EPS and the adhesion of bacterial cells to surface were also considerably reduced due to UV treatment. This study indicates that treatment of water with UV light may be used to control biofilm development on hard surfaces.
Comparition of the Nucleotide Sequences of Wheat Dwarf Virus (WDV) Isolates from Hungary and Ukraine
Authors: TÓBIÁS ISTVÁN , SHEVCHENKO OLEKSIY , KISS BALÁZS , BYSOV ANDRIY , SNIHUR HALINA , POLISCHUK VALERY , SALÁNKI KATALIN , PALKOVICS LÁSZLÓ
Published: November 2019

Wheat dwarf virus (WDV) is the most ubiquitous virus in cereals causing huge losses in both Hungary and Ukraine. The presence of barley-and wheat-adapted strains has been confirmed, suggesting that the barley strain is restricted to barley, while the wheat strain is present in both wheat and barley plants. Five WDV isolates from wheat plants sampled in Hungary and Ukraine were sequenced and compared with known WDV isolates from GenBank. Four WDV isolates belonged to the wheat strain. Our results indicate that WDV-Odessa is an isolate of special interest since it has originated from wheat, but belongs to the barley-adapted strain, providing novel data on WDV biology and raising issues of pathogen epidemiology.
β-glucanase Productivity Improvement via Cell Immobilization of Recombinant Escherichia coli Cells in Different Matrices
Authors: BESHAY USAMA , EL-ENSHASY HESHAM , ISMAIL I.M.K. , MOAWAD HASSAN , ABD-EL-GHANY SAWSAN
Published: November 2019

The studies have been performed to analyze the production of beta-glucanase by a recombinant strain of Escherichia coli immobilized in different matrices. Porous sintered glass SIRAN, Ceramic supporting matrices and Broken Pumice stone as well as SIRAN Raschig-rings were examined for the immobilization of whole bacterial cells. The beta-glucanase activity of bacteria immobilized in CeramTec PST 5 (4-5 mm) was very low. CeramTec PST 5 (1.5-2.5 mm) was found to be the best carrier compared to all other matrices regarding glucanase production (630 U/ml) and compared to enzyme activity produced by free cells (500 U/ml). Different doses of matrices were applied (2, 5, 7, 10 g/lask) in the form of "matrix weight". Using 2 g/flask of CeramTec PST 5 (1.5-2.5 mm) yielded enzyme activity of 630 U/ml). CeramTec gives highest operational stability of beta-glucanase by repeated batch fermentation to 5 cycles, and activity reached 660 U/ml. Scanning electron microscopy observations showed a high number of vegetative cells that continued growth inside the matrices, indicating that beta-glucanase activity improvement was due to the immobilization of the cells.
Utilization of UF-Permeate for Production of β-galactosidase by Lactic Acid Bacteria
Authors: MURAD H.A. , REFAEA R.I. , ALY E.M.
Published: November 2019

Four lactobacilli strains (Lactobacillus bulgaricus, Lactobacillus acidophilus, Lactobacilus casei and Lactobacillus reuteri) were grown in MRS broth and three lactococci strains (Streptococcus thermophilus, Lactococcus lactis subsp. Lactis and Lactococcus lactis subsp. lactis biovar. diacetilactis) were grown in M17 broth. L. reuteri and S. thermophilus were chosen on the basis of the best mean beta-galactosidase activity of 10.44 and 10.01 U/ml respectively, for further studies on permeate-based medium. The maximum production of beta-galactosidase by L. reuteri was achieved at lactose concentration of 6%, initial pH 5.0-7.5, ammonium phosphate as nitrogen source at a concentration of 0.66 g N/L and incubation temperature at 30 degrees C/24 hrs to give 6.31 U/ml. While in case of S. thermophilus, maximum beta-galactosidase production was achieved at 10% lactose concentration of permeate medium, supplemented with phosphate buffer ratio of 0.5:0.5 (KH2PO4:K2HPO4, g/L), at initial pH 6.0-6.5, ammonium phosphate (0.66g N/L) as nitrogen source and incubation temperature 35 degrees C for 24 hrs to give 7.85 U/ml.
SDS-PAGE Heat-Shock Protein Profiles of Environmental Aeromonas Strains
Authors: OSMAN KAMELIA M. , AMIN ZEINAB M. S. , ALY MAGDY A.K. , HASSAN HANY , SOLIMAN WALEED S.
Published: November 2019

Aeromonas microorganisms normally grow at temperatures between 5 degrees C and 45 degrees C and therefore should have high thermotolerance. Thus it was of interest to find out whether A. hydrophila, A. caviae and A. veronii biovar sobria serovars respond to abrupt temperature changes with a heat shock-like response. To this end the present study was undertaken to determine whether Aeromonas species exhibits a heat shock response to different temperatures and time factors. The response of Aeromonas serovars to 24 h and 48 h of thermal stress at 25 degrees C, 42 degrees C and 50 degrees C involved the synthesis of 12-18 heat shock proteins (HSPs) bands with molecular weights ranging between 83.5-103.9 kDa in the high HSP molecular mass and 14.5-12.0 as low molecular mass HSP. Electrophoretic analysis of the HSPs showed that the serovars do not cluster very tightly and also that they are distinct from each other.
Species-Specific Sensitivity of Coagulase-Negative Staphylococci to Single Antibiotics and Their Combinations
Authors: SZYMAŃSKA GRAŻYNA , SZEMRAJ MAGDALENA , SZEWCZYK ELIGIA M.
Published: November 2019

The activity of beta-lactam antibiotics (oxacillin, cloxacillin, cephalotin), vancomycin, gentamicin and rifampicin applied in vitro individually and in combination against 37 nosocomial methicillin-resistant strains of coagulase-negative staphylococci (CNS) was assessed to demonstrate the heterogeneity of this group of bacteria and estimate the chance of the efficacy of such therapy. The strains belonged to four species: Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus cohnii, Staphylococcus hominis. They originated from a hospital environment and from the skin of medical staff of the intensive care unit of a paediatric ward at a university hospital. All strains were methicillin-resistant, according to CLSI standards, but individual strains differed in MIC(ox) values. Susceptibility to other tested antibiotics was also characteristic for the species. The increased susceptibility to antibiotics in combinations, tested by calculating the fractional inhibitory concentration (FIC) index, concerned 26 out of 37 investigated strains and it was a feature of a particular species. Combinations of vancomycin and cephalotin against S. epidermidis and oxacillin with vancomycin were significant, as well as cephalotin and rifampicin in growth inhibition of multiresistant S. haemolyticus strains.
Association between Existence of Integrons and Multi-Drug Resistance in Acinetobacter Isolated from Patients in Southern Iran
Authors: JAPONI SARA , JAPONI AZIZ , FARSHAD SHOREH , ALI AHYA ABDI , JAMALIDOUST MARZIEH
Published: November 2019

Nosocomial infections caused by multi-drug resistant Acinetobacter pose a serious problem in many countries. This study aimed at determining the antibiotic susceptibility patterns and prevalence of different classes of integrons in isolated Acinetobacter. In addition, the association between production of specific bands in PCR assay and magnitude of multi-drug resistance was investigated. In total, 88 Acinetobacter strains were isolated from patients from October 2008 through September 2009. The Minimal inhibitory concentration (MIC) of 12 antibiotics conventionally used in clinics against the isolates, was determined by E-test method. The existence of integron classes was investigated by PCR assay through the amplification of integrase genes. The most effective antibiotic against Acinetobacter was colistin with 97.7% activity, followed by imipenem (77.3%) and meropenem (72.7%). The presence ofintegron classes 1 and 2 in 47 (53.4%) isolates was confirme, However, no class 3 was detected. The proportion of class 1, compared with class 2, was high (47.7% vs. 3.4%). The association between multi-drug resistance to norfloxacin, ceftazidime, gentamicin, ciprofloxacin, cefepime and amikacin and the presence of integrons was statistically significant. However, the association was not remarkable in many of the isolates which exhibited resistance to the rest of antibiotics. This may imply that in addition to integrons, other resistance determinants such as transposon and plasmid may also contribute to resistance. To reduce the pressure on sensitive isolates, comprehensive control measures should be implemented. Furthermore, wise application of effective antibiotics could help alleviate the situation. Colistin is the most effective antibiotic in vitro against Acinetobacter.
Dissemination of Class 1, 2 and 3 Integrons among Different Multidrug Resistant Isolates of Acinetobacter baumannii in Tehran Hospitals, Iran
Authors: TAHERIKALANI MOROVAT , MALEKI ABBAS , SADEGHIFARD NOURKHODA , MOHAMMADZADEH DELBAR , SOROUSH SETAREH , ASADOLLAHI PARISA , ASADOLLAHI KHAIROLLAH , EMANEINI MOHAMMAD
Published: November 2019

A total of 100 non-duplicate Acinetobacter baumannii isolates were collected from different hospitals in Tehran and were confirmed as A. baumannii by conventional biochemical and API testing. Antimicrobial susceptibility of these isolates was checked by a disk diffusion method in accordance with CLSI guidelines. The isolates were then detected as carrying class 1 and 2 integron gene cassettes by PCR evaluation and then genotyped by REP-PCR. More than 50% (n = 50) of the isolates were multidrug resistant. The results showed that more than 80% of all multidrug resistant A. baumannii strains carry a class 1 integron. Distribution of IntI 1 and IntI2 among A. baumannii isolates was 58% and 14%, respectively. Analysis of a conserved segment of class 1 integron showed a range from 100 bp to 2.5 kb. REP-PCR fingerprinting showed more than 20 genotypes among A. baumannii strains. TIhere was no relationship between REP genotypes and the distribution of different classes of integrons. This is a comprehensive study on the distribution of different classes of integrons among A. baumannii in Iran. Considering the exact role of integrons in coding drug resistance in bacteria, the findings of this study could help us find antimicrobial resistant mechanisms among A. baumannii isolates in Iran.
Host Response to the Presence of Helicobacter spp. DNA in the Liver of Patients with Chronic Liver Diseases
Authors: RYBICKA MAGDA , NAKONIECZNA JOANNA , STALKE PIOTR , BIELAWSKI KRZYSZTOF PIOTR
Published: November 2019

Literature data indicate an association between the presence of Helicobacter spp. in the liver and the development of hepatocellular carcinoma (HCC). However, the role of H. pylori infections in chronic liver diseases (CLD) remains controversial. The aim of this study was to detect Helicobacter spp. DNA in patients with CLD, and to investigate the host response to the presence of the bacterium in the liver. Helicobacter spp. DNA was detected in 59% samples. H.pylori was the most prevalent species (94%). We estimated the expression level of IL-1 and IL-8 genes. The presence of Helicobacter spp. did not have a significant effect on the gene expression of IL-8 and IL-1.
An Update on Some Structural Aspects of the Mighty Miniwall
Authors: MARKIEWICZ ZDZISŁAW , POPOWSKA MAGDALENA
Published: November 2019

Peptidoglycan (PG), the mighty miniwall, is the main structural component of practically all bacterial cell envelopes and has been the subject of a wealth of research over the past 60 years, if only because its biosynthesis is the target of many antibiotics that have successfully been used in the treatment of bacterial infections. This review is mainly focused on the most recent achievements in research on the modification of PG glycan strands, which contribute to the resistance of bacteria to the host immune response to infection and to their own lytic enzymes, and on studies on the spatial organization of the macromolecule.
A New Rapid and Cost-Effective Method for Detection of Phages, ICEs and Virulence Factors Encoded by Streptococcus pyogenes
Authors: BOREK ANNA L. , WILEMSKA JOANNA , IZDEBSKI RADOSŁAW , HRYNIEWICZ WALERIA , SITKIEWICZ IZABELA
Published: November 2019

Streptococcus pyogenes (group A Streptococcus, GAS) is a human pathogen that causes diseases of various intensity, from mild strep throat to life threatening invasive infections and postinfectional sequelae. S. pyogenes encodes multiple, often phage encoded, virulence factors and their presence is related to severity of the disease. Acquisition of mobile genetic elements, carrying virulence factors, as phages or ICEs (integrative and cojugative elements) has been shown previously to promote selection of virulent clones. We designed the system of eight low volume multi- and one singleplex PCR reactions to detect genes encoding twenty virulence factors (spd3, sdc, sdaB, sdaD, speB, spyCEP, scpA, mac, sic, speL, K, M, C, I, A, H, G, J, smeZ and ssa) and twenty one phage and ICE integration sites described so far for S. pyogenes. Classification of strains based on the phage and virulence factors absence or presence, correlates with PFGE MLST and emm typing results. We developed a novel, fast and cost effective system that can be used to detect GAS virulence factors. Moreover, this system may become an alternative and effective system to differentiate between GAS strains.
Extracellular Xylanase Production by Fusarium Species in Solid State Fermentation
Authors: ARABI MOHAMMED IMAD EDDIN , BAKRI YASSER , JAWHAR MOHAMMED
Published: November 2019

Fusarium sp. has been shown to be a promising organism for enhanced production of xylanases. In the present study, xylanase production by 21 Fusarium sp. isolates (8 Fusarium culmorum, 4 Fusarium solani, 6 Fusarium verticillioides and 3 Fusarium equiseti) was evaluated under solid state fermentation (SSF). The fungal isolate Fusarium solani SYRN7 was the best xylanase producer among the tested isolates. The effects of some agriculture wastes (like wheat straw, wheat bran, beet pulp and cotton seed cake) and incubation period on xylanase production by F. solani were optimized. High xylanase production (1465.8 U/g) was observed in wheat bran after 96 h of incubation. Optimum pH and temperature for xylanase activity were found to be 5 and 50 degrees C, respectively.
Screening of Actinomycetes from Mangrove Ecosystem for L-asparaginase Activity and Optimization by Response Surface Methodology
Authors: USHA RAJAMANICKAM , MALA KRISHNASWAMI KANJANA , VENIL CHIDAMBARAM KULANDAISAMY , PALANISWAMY MUTHUSAMY
Published: November 2019

Marine actinomycetes were isolated from sediment samples collected from Pitchavaram mangrove ecosystem situated along the southeast coast of India. Maximum actinomycete population was noted in rhizosphere region. About 38% of the isolates produced L-asparaginase. One potential strain KUA106 produced higher level of enzyme using tryptone glucose yeast extract medium. Based on the studied phenotypic characteristics, strain KUA106 was identified as Streptomyces parvulus KUA106. The optimization method that combines the Plackett-Burman design, a factorial design and the response surface method, which were used to optimize the medium for the production of L-asparaginase by Streptomycetes parvulus. Four medium factors were screened from eleven medium factors by Plackett-Burman design experiments and subsequent optimization process to find out the optimum values of the selected parameters using central composite design was performed. Asparagine, tryptone, d) extrose and NaCl components were found to be the best medium for the L-asparaginase production. The combined optimization method described here is the effective method for screening medium factors as well as determining their optimum level for the production of L-asparaginase by Streptomycetes parvulus KUAP106.
A Comparative Study on the Activity and Antigenicity of Truncated and Full-length Forms of Streptokinase
Authors: ARABI REZA , ROOHVAND FARZIN , NOROUZIAN DARYOUSH , SARDARI SOROUSH , AGHASADEGHI MOHAMMAD REZA , KHANAHMAD HOSEIN , MEMARNEJADIAN ARASH , MOTEVALLI FATEMEH
Published: November 2019

Application of streptokinase (SK) as a common and cost-effective thrombolytic drug is limited by its antigenicity and undesired hemorrhagic effects. Prior structural/functional and epitope-mapping studies on SK suggested that removal of 59 N-terminal residues led to its fibrin dependency and identified SK antigenic regions, respectively. Following in silico analyses two truncated SK proteins were designed and compared for their fibrin specificity and antigenicity with the full-length SK. Computer-based modeling was used to predict the effect of vector (pET41a)-born protein tags on the conformation of SK fragments. SK60-386, SK143-386 and full-length SK (1-414) were separately cloned, expressed in BL21 E. coli cells and confirmed by Western-blotting. Functional activity of the purified proteins was evaluated with chromogenic and clot lysis assays and their antigenicity was tested by ELISA assay using rabbit anti-streptokinase antibody. As expected, chromogenic bioassay showed a major activity decline for SK60-386 and SK143-386 (83 and 91 percent, respectively), compared to SK1-414. However, in clot lysis assay, which is a fibrin-dependent pharmacopoeia-approved test, SK60-386 and SK143-386 were respectively 35 and 31 percent more active though lysed the clots slower than full-length SK. Antigenic analysis also indicated significant decrease in ELISA signals obtained for truncated proteins compared to SK1-414 (45 and 28 percent less reactivity for SK143-386 and SK60-386, respectively, p < 0.0001). The results of this study for the first time pointed to SK143-386 and SK60-386, as improved SK derivatives with increased fibrin-selectivity and decreased antigenicity as well as acceptable bioactivity profiles in a pharmacopoeia-based analysis, which deserve more detailed pharmacological studies.
Infections Caused by RSV among Children and Adults during Two Epidemic Seasons
Authors: PANCER KATARZYNA , CIĄĆKA AGNIESZKA , GUT WŁODZIMIERZ , LIPKA BOŻENA , MIERZEJEWSKA JUSTYNA , MILEWSKA-BOBULA BOGUMIŁA , SMORCZEWSKA-KILJAN ANNA , JAHNZ-RÓŻYK KARINA , DZIERŻANOWSKA DANUTA , MADALIŃSKI KAZIMIERZ , LITWIŃSKA BOGUMIŁA
Published: November 2019

Respiratory Syncytial Virus (RSV) is one of the most common causes of lower respiratory tract infections in young children, immunocompromised patients (children and adults), patients with chronic respiratory diseases and elderly people. Reinfections occur throughout the life, but the severity of disease decreased with subsequent infection. The aim of this study was to analyze the frequency of RSV infections in two selected subpopulations: young children (below 5 y.) and adults with chronic respiratory diseases (25-87 y.). Nasopharyngeal swabs (334) collected from October 2008 to March 2010 were examined. The presence of RSV genome was determined by RT-PCR and the presence of RSV antigen by quick immunochromatographic test. Positive results of RT-PCR were found in 45.2% of all swabs: 48.6% samples in 2008; 41.5% in 2009; 50.8% in 2010. The highest frequency of RSV-positive samples was in fall-winter months, but differences in RSV epidemic seasons were found. In the first season (2008-2009) an increased number of RSV infections was observed from November 2008, but in the second season--from January 2010. Generally, the frequency of RSV-positive RT-PCR among children was 53%, among adults 25%. The highest difference was observed in the first three-month period of 2010. RT-PCR positive samples were found in 68.5% of children and 5.9% of adults. However, the RSV antigen was found in 44.4% of samples collected from adults in this period. Our results indicate that the contribution of RSV infections during epidemic season of respiratory tract infections in Poland was really high among children and adults.
Detection of Giardia intestinalis Assemblages A, B and D in Domestic Cats from Warsaw, Poland
Authors: JAROS DOROTA , ZYGNER WOJCIECH , JAROS SŁAWOMIR , WĘDRYCHOWICZ HALINA
Published: November 2019

Giardia intestinalis is a complex species divided into 7 assemblages (A - G). Two of them (A and B) are infective for both humans and animals. In cats four assemblages can occur: A, B, D, and F Assemblages A and B infect either cats, dogs and humans, assemblage D infects cats and dogs and assemblage F only cats. The purpose of this study was to determine the prevalence and genotypes of G. intestinalis in cats from Warsaw. From November 2006 to March 2007 a hundred sixty samples of stool were collected and examined by light microscopy. G. intestinalis cysts were detected in 3.75% of samples. DNA extracted from positive samples was used as template for PCR-RFLP using Giardia specific primers and the amplicons were sequenced. A comparison of the obtained DNA sequences with the Giardia sequences in the GeneBank database revealed assemblage A in 1.25% of the investigated cats, assemblage B in 1.25% and D in 1.25%.
Evaluation of a Rapid Culture-Based Screening Test for Detection of Methicillin Resistant Staphylococcus aureus
Authors: FWITY BOUSHRA , LOBMANN RALF , AMBROSCH ANDREAS
Published: November 2019

The performance of a culture based assay, BacLite Rapid MRSA for the rapid detection (5 hours) of methicillin resistant Staphylococcus aureus (MRSA) from specimens (n = 377) obtained from nares, throat, wounds and perineum was investigated. Compared to culture based reference methods (chromogenic MRSA ID (bioMerieux)), selective enrichment broth, PBP2' latex agglutination (Oxoid) and VITEK 2 identification (bioMerieux), an overall sensitivity of 71% with a 82% specificity and a negative predictive value (NPV) of 95% was provided. The Baclite test is rapid and easy to use and has the advantage of a culture-based detection method for MRSA.
Urinary Tract Infections of Escherichia coli Strains of Chaperone-Usher System
Authors: ZALEWSKA-PIĄTEK BEATA M.
Published: November 2019

Urinary tract infections are a very serious health and economic problem affecting millions of people each year worldwide. The most common etiologic agent of this type of bacterial infections, involving the upper and lower urinary tract, are E. coli strains representing approximately 80% of cases. Uropathogenic E. coli strains produce several urovirulence factors which can be divided into two main types, surface virulence factors and exported virulence factors. Surface-exposed structures include mainly extracellular adhesive organelles such as fimbriae/pili necessary in adhesion, invasion, biofilm formation and cytokine induction. Among the surface-exposed polymeric adhesive structures there are three most invasive groups, type 1 pili, type P pili and Dr family of adhesins which are bioassembled via the conserved, among Gram-negative bacteria, chaperone-usher secretion system. Type 1 and P-piliated E. coli cause cystitis and pyelonephritis. The Dr family of adhesins recognizing DAF receptor is responsible for cystitis, pyelonephritis (especially in pregnant women) and diarrhoea (in infants). In addition, Dr-positive E. coli strains carry the risk of recurrent urinary tract infections. Pyelonephritis in pregnant women leads to a series of complications such as bacteremia, urosepsis, acute respiratory distress syndrome and even death. In the era of increasing drug resistance of bacteria, the development of vaccines, drugs termed pilicides and inhibitors of adhesion may be a promising tool in the fight against urogenital infections.
Gelatinase-Associated Phenotypes and Genotypes Among Clinical Isolates of Enterococcus faecalis in Poland
Authors: STRZELECKI JANUSZ , HRYNIEWICZ WALERIA , SADOWY EWA
Published: November 2019

Enterococcus faecalis is an important nosocomial pathogen causing serious invasive infections. One of the virulence factors of this pathogen, gelatinase GelE, is a protease whose gene expression is regulated by the Fsr quorum sensing system. In this study, we used a well-characterized collection of 153 clinical E. faecalis isolates to investigate the distribution of genes involved in gelatinase expression. Although 140 isolates (91% of the group) harbored the gelE gene, only 81 isolates (53%) produced active gelatinase. The gelatinase-negative phenotype was found in several unrelated clones, and appeared to be caused by various genetic events. Isolates of the hospital-adapted clonal complex 2 (CC2) and of CC40 were uniformly gelatinase-positive, while all the CC87 isolates contained the 23.9 kb deletion encompassing most of the fsr locus and were gelatinase-negative. No significant differences among isolates of different clinical origin and gelatinase activity or presence of the fsr genes were found with the exception of isolates from cerebrospinal fluid, which were more often gelatinase-positive than colonizing isolates.
Multiple-Locus Variable Number of Tandem Repeats Fingerprinting (MLVF) and Virulence Factor Analysis of Methicillin Resistant Staphylococcus aureus SCCmec type III
Authors: EMANEINI MOHAMMAD , JABALAMELI LEILA , IMAN-EINI HOSSEIN , ALIGHOLI MARZIEH , GHASEMI AMIR , NAKHJAVANI FARROKH AKBARI , TAHERIKALANI MOROVAT , KHORAMIAN BABAK , ASADOLLAHI PARISA , JABALAMELI FERESHTEH
Published: November 2019

Methicillin resistant Staphylococcus aureus (MRSA), particularly strains with type III staphylococcal cassette chromosome mec (SCCmec), represent a serious human pathogen in Tehran, Iran. The disease-causing capability depends on their ability to produce a wide variety of virulent factors. The prevalence of exotoxin genes and multiple-locus variable number of tandem repeats fingerprinting (MLVF) profile among MRSA isolates, from patients in Tehran, was evaluated by PCR and Multiplex-PCR. The MLVF typing of 144 MRSA isolates with type III SCCmec produced 5 different MLVF types. Generally, 97.2% (140/144) of all the isolates were positive for at least one of the tested exotoxin genes. The most prevalent genes were hld, found in 87.5% (126/144) of the isolates followed by lukE-lukD and hla found in 72.9% (105/144) and 70.1% (101/144) of the isolates, respectively. The tst gene, belonging to MLVF types I, IV and V, was found among three of the isolates from blood and wound samples. The sea gene was detected in 58.3% (84/144) of the isolates and the sed and see genes were found in one isolate with MLVF type V. The coexistence of genes was observed in the 87.5% (126/144) of the isolates. The rate of coexistence of hld with lukE-lukD, hla with lukE-lukD and sea with lukE-lukD were 66.7% (96/144), 44.4% (64/144) and 44.4% (64/144), respectively. The present study demonstrated that MRSA strains with type III SCCmec show different MLVF patterns and exotoxin profiles.
Antibiotic Sensitivity and Sequence Amplification Patterns of Genes in Multidrug Resistant Enterobacteria Isolates from Processed Foods in Some West African Countries
Authors: OWOSENI ABIMBOLA ADETOKUNBOH , ONILUDE ABIODUN ANTHONY
Published: November 2019

Diarrhoea, dysentery and other diseases due to other enteric bacteria have reportedly been found to resist chemotherapeutic treatment in some West African communities with fatal consequences in some cases. This study was carried out to determine multidrug resistance patterns of Enterobacteria isolates from processed ready-to-eat foods. Indigenously processed food samples of different types were collected from two Francophone and two Anglophone countries in the West African sub-region during the wet and dry seasons of a sampling period of two years. Enterobacteria were isolated from the samples using standard techniques. Amplification of chromosomal DNA of the isolates using the Polymerase Chain Reaction was carried out. The results obtained were subjected to statistical analyses. All isolates showed resistance to cefuroxime (90.7%), nitrofurantoin (90.6%), augmentin (86.1%) and ampicillin (51.2%) while all were sensitive to gentamycin and ciprofloxacin. There was amplification indicating the presence of invA gene at a position of 240 bp. There was no amplification at all for the spvC gene in any of the isolates tested. Multidrug resistant enteric bacteria in these foods containing the invA gene could lead to infections with uncontrolled antibiotic use. The presence of enteric bacteria in the foods analyzed which provide undeniable evidence of the poor microbiological quality of these foods could form the basis of a useful databank in formulation of food-borne disease control and prevention strategies.
Use of Potato Extract Broth for Culturing Root-Nodule Bacteria
Authors: MARTYNIUK STEFAN , OROŃ JADWIGA
Published: November 2019

Liquid media containing potato extract and 1% of glucose or sucrose were used to culture root-nodule bacteria (rhizobia) in shaken Erlenmeyer flasks. For comparison, these bacteria were also cultured in yeast extract-mannitol broth (YEMB) as a standard medium. Proliferation of rhizobia was monitored by measuring optical densities (OD550) of the cultures and by plate counting of the viable cells (c.f.u) of the bacteria. In general, multiplication of the rhizobia in potato extract-glucose broth (PEGB) and potato extract-sucrose broth (PESB) was markedly faster, as indicated by higher values of OD550, than in YEMB. The numbers of R. leguminosarum by. vicae GGL and S. meliloti 330 in PEGB and PEGB were high and ranged from 1.2 x 10(10) to 4.9 x 10(10) mL(-1) after 48 h of incubation at 28 degrees C. B. japonicum B3S culture in PEGB contained 6.4 x 10(9) c.f.u. ml(-1) after 72 h of incubation. PEGB and YEMB cultures of the rhizobia were similar with respect to their beneficial effects on nodulation of the host-plants of these bacteria.
Tick – Borne Infections as a Cause of Heart Transplantation
Authors: MĄCZKA ILONA , CHMIELEWSKI TOMASZ , WALCZAK EWA , RÓŻAŃSKI JACEK , RELIGA GRZEGORZ , TYLEWSKA-WIERZBANOWSKA STANISŁAWA
Published: November 2019

Many bacterial species can be a cause of various heart diseases, such as: Borrelia burgdorferi sensu lato, Coxiella burnetii and Bartonella spp. The aim of the present studies was to establish if any tick-borne infections can contribute to serious heart disorders resulting in the need for heart transplantation. Myocardium, aortic and mitral valve samples from hearts removed from patients undergoing heart transplantation were tested. The presence of Bartonella spp., Borrelia afzeli and C. burnetii bacteria in malfunctioning human hearts has been shown. DNA of Bartonella spp., B. burgdorferi and C. burnetii were detected in various parts of tested hearts. DNA of B. afzelii and Bartonella spp. were found in the aortic valves. DNA of C. burnetii was detected in the myocardium. Mixed infections with Bartonella spp. and C. burnetii were also observed. Obtained results indicate that diagnosis of Bartonella spp., B. burgdorferi C. burnetii and Rickettsia spp. infections should be considered in cases of infectious endocarditis with negative blood cultures.
Latent Mycobacterium tuberculosis Infection – Pathogenesis, Diagnosis, Treatment and Prevention Strategies
Authors: DRUSZCZYŃSKA MAGDALENA , KOWALEWICZ-KULBAT MAGDALENA , FOL MAREK , WŁODARCZYK MARCIN , RUDNICKA WIESŁAWA
Published: November 2019

One third of the earths population is infected with Mycobacterium tuberculosis (Mtb), but only 5-10% of the infected individuals develop active tuberculosis (TB) over their lifetime. The remaining 90-95% stay healthy and are called latently infected individuals. They are the biggest reservoir of the tubercle bacilli and identifying the cases of latent TB is a part of the global plan of TB control. From the clinical point of view detection of latent TB infections (LTBI) in individuals with the highest active TB risk including cases of HIV infection, autoimmune inflammatory diseases or cancer, is a priority. This review summarizes the recent findings in the pathogenesis of latent TB, its diagnosis, treatment and prevention.