The site preferences within the structures of half-Heusler compounds have been evaluated through a machine-learning approach. A support-vector machine algorithm was applied to develop a model which was trained on 179 experimentally reported structures and 23 descriptors based solely on the chemical composition. The model gave excellent performance, with sensitivity of 93%, selectivity of 96%, and accuracy of 95%.
View Article and Find Full Text PDFThe aim of the study was to obtain information on parents' attitudes towards vaccinations included in the childhood immunisation schedule. Computer-assisted telephone interviews (CATI) method was used. The interviews were collected from parents who had children aged three years old.
View Article and Find Full Text PDFThe aim of the study was to obtain information on parents' knowledge about mandatory and recommended vaccinations in Poland. Computer-assisted telephone interviews (CATI) method was used. The interviews were collected from parents who had children aged < or = 3 years.
View Article and Find Full Text PDFThe study aimed at identification of splenocytes genes expression induced after immunization with whole-cell or acellular pertussis vaccines and subsequent challenge with B. pertussis strains of different ptxS1/prn genes alleles in correlation with differences in bacteria elimination from the lung tissue. Investigations were performed using DNA microcarriers.
View Article and Find Full Text PDFStudies concerned evaluation of differences between parameters of cell-mediated immunity in mice, induced with whole-cell and acellular pertussis vaccines with subsequent challenge with B. pertussis strains harbouring different ptxS1/prn allele genes. In the study, concentrations of IFN-gamma/Il-2 and 1l-4/Il-5 in supernatants of cultured mice splenocytes have been determined to evaluate differences in Th1 or Th2 lymphocytes subpopulation response.
View Article and Find Full Text PDFThe study is based on assumption that B. pertussis strains harbouring different allele variants of genes encoding subunit S1 of pertussis toxin and pertactin might be eliminated with different efficiency from lung tissue of mice which were immunized with whole-cell and acellular pertussis vaccines. It has been assumed that strains containing combinations of genes alleles which were not prevalent since 1990-ties are consisting of mutated strains in respect to pertussis toxin subunit S1 and pertactin, and are capable to decrease efficiency of pertussis vaccines.
View Article and Find Full Text PDFIn the study the usefulness of genotyping methods for genetic variability examinations of non-typeable H. influenzae strains circulating in population as well as level the variability of NTHi strains isolated from healthy children and from symptomatic infection cases have been evaluated. Among genotyping methods evaluated, AFLP method of the MfeI/BglII set has been found most useful to study level of genetic variability of NTHi strains population.
View Article and Find Full Text PDFClose contacts between children attending day-care centres, orphanages or similar institutions favours mutual transmission of infections with nontypeable H. influenzae (NTHi) strains. NTHi are transmitted via air-droplets or via direct contact with respiratory system exudates from nonsymptomatic carriers.
View Article and Find Full Text PDFClinical isolates of Bordetella pertussis collected during the year 2004 (n = 153) in eight European countries, Denmark, Finland, France, Germany, The Netherlands, Poland, Sweden, and United Kingdom, were analyzed by pulsed-field gel electrophoresis (PFGE), and their PFGE profiles were compared with those of isolates collected in 1999 (n = 102). The 255 isolates produced 59 distinct PFGE profiles. Among the 153 isolates from 2004, 36 profiles were found, while within the 102 isolates from 1999, 33 profiles were detected.
View Article and Find Full Text PDFThe study was based on hypothesis that in the nontypeable population of H. influenzae strains isolated from children there are some genetically predisposed to induce symptomatic infection in children and that they might be divided into different groups depending on profiles of genes encoding main adhesins synthesis. The work aimed at analysis of distribution of genes encoding adhesins and evaluation of domination possibility of some strains representing particular adhesins genes profiles among NTHi population.
View Article and Find Full Text PDFIn this study, Amplified Fragment Length Polymorphism (AFLP) method was used to track differences among human and animal isolates of B. pertussis, B. parapertussis and B.
View Article and Find Full Text PDFMed Dosw Mikrobiol
August 2006
In this study, RandomAmplified Polymorphic DNA (RAPD) method was used to track differences among human and animals isolates of eight known species of Bordetella genus. One hundred representative strains of these species from international and Polish bacterial collections were genotyped according to RAPD protocols using primer 1254 or 1247. Problems with reproducibility and discriminatory power, frequently discussed in literature, have been overcome by precise optimization procedure, which allowed to achieve reliable conditions for Bordetella species analysed.
View Article and Find Full Text PDFGoal of the work was to evaluate the differences level among H. influenzae strains of b serotype isolated from children attending day-care centres and orphanages and among strains isolated from invasive infections. In the work PFGE in Hib strains transmission examination and for epidemiological studies among three sources of invasive infection was applied.
View Article and Find Full Text PDFThe frequency of capsulated or non-capsulated Haemophilus influenzae strains colonisation among children attending day-care centres or orphanages has been studied. Detection of capsulated or non-capsulated H. influenzae strains has been compared for agglutination test and PCR.
View Article and Find Full Text PDFThis study aimed to identify and to evaluate the level of potency fluctuations of the pertussis component of Polish-produced DTP vaccine lots produced within 1972-2001 due to the changes having occurred in production and potency testing procedures. Obtained results showed high consistency of the production and control tests confirming relevant quality of country-produced DTP vaccine.
View Article and Find Full Text PDFThis study aimed to identify and to evaluate the level of potency fluctuations of the pertussis component of Polish-produced DTP vaccine lots produced within 1972-2001 due to the changes having occurred in production and potency testing procedures. The study confirms that higher potency values were obtained for vaccine lots produced since 80-ties, e.g.
View Article and Find Full Text PDFAutomated amplified fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) techniques with fluorescently labelled primers were used to track differences among isolates of the eight known species of the Bordetella genus. Eighty-one representative strains of these species from international and Polish bacterial collections were genotyped according to RAPD protocols using primer 1254 or 1247, and AFLP involving EcoRI/MseI or newly designed SpeI/ApaI restriction/ligation/amplification procedures. By comparing AFLP and RAPD data, it was concluded that the discriminatory power of AFLP is higher in comparison with RAPD for both intra- and inter-species differentiation of isolates of the Bordetella genus.
View Article and Find Full Text PDFIn Poland, similar to many highly immunized Western countries, a recent increase in cases of pertussis has been observed. This study aims to evaluate the level of potency fluctuations of the pertussis component of Polish-produced DTP vaccine due to the changes having occurred in production and potency testing procedures. We compared the potency of the pertussis component of DTP vaccine lots produced and evaluated in similar periods and with similar production and testing procedures.
View Article and Find Full Text PDFPrzegl Epidemiol
December 2004
Although composition of acellular pertussis vaccines is better defined than whole-cell vaccines, differences in the formulation, content, and detoxification of pertussis vaccine antigens led to a unique character of each of differently produced acellular vaccine. Currently used methods for laboratory evaluation of whole-cell pertussis vaccine efficacy were found not suitable for acellular vaccines. There is a strong need to perform analysis and evaluation of the safety and efficacy profiles of acellular pertussis vaccines combined with other vaccine antigens (e.
View Article and Find Full Text PDFThe present study indicates that the appearance of the B. pertussis harbouring prn2 gene allele variant (not found among clinical isolates before 1990s) may have been induced by long-term vaccination in Poland with DTP-composed vaccine strains presenting exclusively prn1. However, ptxS1A allele of pertussis toxin subunit S1 encoding gene, predominant in the currently isolated B.
View Article and Find Full Text PDFBackground: Since 1997, an unexpected 2-5-fold increase in the incidence of pertussis has been reported in Poland in comparison with the previous 10 years, although the introduction of the diphtheria-tetanus-pertussis (DTP) vaccination in 1960 reduced the incidence of pertussis approximately 100-fold in the 1980s. The aim of the study was to analyse all available data on pertussis in Poland to identify the risks associated with its re-emergence.
Methods: Available data on notification, incidence, mortality, hospitalization, geographical distribution, incidence according to age, and diagnosis of pertussis were collected from national surveillance monographs and statistically evaluated.
Neurotoxins produced by strains of Clostridium sp. are belonging to the most toxic biological substances. In the study phenotypes and genotypes of C.
View Article and Find Full Text PDFRandomly amplified polymorphic DNA (RAPD) and automated amplified-fragment length polymorphism (AFLP) techniques with fluorescently labelled primers were used to type non-serotypable Haemophilus influenzae (NTHI) isolates. Eighty-seven isolates from healthy children attending day-care centres or living at orphanages in southern Poland were investigated. Through comparison of the AFLP data with RAPD analysis, it has been concluded that the discriminatory power of AFLP for NTHI typing is higher than RAPD.
View Article and Find Full Text PDFPrzegl Epidemiol
November 2003
In some highly immunized countries with long history of pertussis vaccination (The Netherlands, Finland, Poland, USA, France, Great Britain) differences in the DNA patterns and ptxS1 and prn alleles present in B. pertussis strains used for production of pertussis component in the DTP vaccine, in comparison to strains presently isolated from clinical materials have been found. Studies on efficacy of whole-cell and acellular pertussis vaccines in elimination of B.
View Article and Find Full Text PDFVariability of B. pertussis genome concerning S1 subunit of pertussis toxin (ptxS1) and pertactin (prn) genes has recently been recognised. Studies clearly showed differences in the DNA patterns and ptxS1 and prn alleles present in B.
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