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J Jenek

Publications and source records attributed to J Jenek.

13 recordsLinked to original sources

[Ticks Ixodes ricinus (Linnaeus, 1758) from selected municipal forests of the city Poznań and their infection with the spirochetes Borrelia burgdorferi senso lato].

The results of research (1997-1998) on the occurrence of the spirochetes Borrelia burgdorferi s.l. in ticks Ixodes ricinus (L.) in selected municipal forests of the city of Poznań (localities--districts of Poznań: 1 Debiec, 2 Marcelin, 3 Golecin and Wola, 4 Krzyzowniki and Smochowice, 5 Kiekrz and Strzeszynek, 6 Morasko, 7 Piatkowo, 8 Umultowo, 9 Naramowice and Rózany Młyn, 10 Malta and Antoninek) are presented. A total of 1432 ticks were collected from 10 localities (748 larvae, 590 nymphs, 47 males, and 47 females). Out of this number, 266 specimens were selected at random for further analysis (20 larvae, 160 nymphs, 44 males, and 42 females) which were then tested for the presence of the spirochetes using the PCR technique (tab. I-III, fig. 1). Spirochetes were found in 60 specimens (22.6%). Percentages of infected nymphs and males were similar: 25.6% and 27.3%, respectively. The level of infection of females was lower (14.3%) and of larvae lowest (5.0%). Infected ticks were found in all ten localities, but their proportions differed from site to site and varied from 9.5% (Piatkowo) to 34.6% (Krzyzowniki and Smochowice). Special attention was devoted to those municipal woods where ticks were abundant (Kiekrz and Strzeszynek, as well as Malta and Antoninek, and relatively numerous Debiec) and where their extensiveness of infestation was high (Krzyzowniki and Smochowice: 34.6%; Debiec: 29.6%; Naramowice and Rózany Młyn: 28.6%; Malta and Antoninek: 28.1%; and Golecin and Wola: 26.9%). After summing up all the data from the literature on Wielkopolska and the city of Poznań, the mean extensiveness of infestation in Wielkopolska turns out to be 21.8% and in Poznań slightly higher, 22.2% (tab. IV). The infection levels of the particular developmental stages are different, though: highly variable in nymphs (8.3-25.6%), and more stable in males (22.0-27.3%) and females (22.0-24.5%).

Animals↗

[Incidence of Borrelia burgdorferi sensu lato spirochetes in Ixodes ricinus ticks from a museum collection evaluated by PCR].

Ixodes ricinus ticks (total n = 51:14 larvae, 16 nymphs, 17 females and 11 males) collected at 21 different sites during 1948-1987 were examined individually for the presence of Borrelia burgdorferi sensu lato spirochaetes. Detection of spirochaetes was carried out by polymerase chain reaction (PCR) using primers complementary to chromosomal sequence. Borreliae were found in 3 (3.56%) examined ticks (nymphs) collected at the same site (two in June, 1952 and one in August, 1987). The low number of infected ticks found in this investigation do not reflects real infection rate in tick population.

Animals↗

[The evaluation of Borrelia burgdorferi sensu lato spirochaetes distribution in Ixodes ricinus ticks collected in selected regions of Wielkopolska+ regions by polymerase chain reaction (PCR) method].

Ixodes ricinus ticks (total n = 298: 24 nymphs, 156 females and 112 males) collected from vegetation at 7 different sites were examined individually for the presence of Borrelia burgdorferi sensu lato spirochaetes. Detection of spirochaetes was carried out by polymerase chain reaction (PCR) using primers complementary to chromosomal sequence. Borreliae were evident in 73 (24.5%) examined ticks. Females were infected in 28.8%, males in 22.0% and nymphs in 8.3%. Infection rate in tick population in particular investigated sites differed, however. The highest one-46.4%-was calculated for ticks collected in Konin province and the lowest one--11.5%--for ticks collected at site in Gorzów province.

Animals↗

Biotyping, ribotyping and esterase electrophoresis as epidemiological tools for Acinetobacter baumannii.

An epidemiological survey was carried out over a one-week period to assess the spread of Acinetobacter baumannii in a medical intensive care unit. Fifty strains were isolated from patients colonized or infected by the organism and from a hospital environment. These strains belonged to biotypes 9 or 18. The rRNA gene restriction patterns (using EcoRI and PvuII as restriction endonucleases) and the esterase electrophoretic profiles were determined on 31 strains, using as comparison strain isolates from another intensive care unit of our hospital and from two other French hospitals. Four EcoRI ribotypes, four PvuII ribotypes and six esterase profiles were identified. All biotype 9 strains isolated in our hospital presented the same ribotype after EcoRI digestion, the same ribotype after PvuII digestion and the same zymotype. The same observation was made on most of the biotype 18 strains. Biotyping is an appropriate method for screening of strains, and ribotyping and esterase electrophoresis could be used as additional methods to delineate outbreaks of nosocomial infections caused by A. baumannii.

Acinetobacter↗

[Occurrence of Helicobacter pylori strains resistant to metronidazole].

This study describes results of in vitro examination of susceptibility to metronidazole of clinical strains of Helicobacter pylori isolated from patients with gastritis. The susceptibility was determined by disc diffusion test. H. pylori was isolated from 44 (67.7%) of patients. Thirty six (81.8%) of the strains were resistant to metronidazole: 17 (85%) from 20 strains isolated from women and 19 (79.2%) from 24 strains isolated from men. This study emphasises the importance of monitoring the drug resistance of H. pylori during therapy.

Adult↗

Absence of genotoxic activity of refined smoke flavor (RSF) in two bacterial short-term tests.

The genotoxic activities of refined smoke flavor (RSF) produced in Poland and used in food processing were investigated in 2 bacterial short-term tests. Its mutagenic activity was examined in the Salmonella/histidine plate assay and its SOS-inducing capacity in the SOS Chromotest both without and with 'activation' by a rat liver homogenate. No genotoxic activity was detected using these 2 bacterial tests.

Animals↗

Genotoxic activity of two furan analogues of benzo[a]pyrene and their 2-nitro derivatives.

We measured the genotoxic activities in two bacterial tests, the Salmonella/histidine assay (a reverse mutation assay) and the SOS Chromotest (an assay for SOS induction in E. coli), of two pairs of isomeric furan analogues of benzo[a]pyrene: pyreno[1,2-b]furan (R7490) and pyreno[2,1-b]furan (R7692) and their 2-nitro derivatives, 8-nitro-pyreno[1,2-b]furan (R7489) and 8-nitro-pyreno[2,1-b]furan (R7691). We found that: For all 4 compounds, the responses were correlated in the two tests. For the 2-nitro derivatives, R7489 and R7691, the responses were extremely high, reaching SOS-inducing potencies of 5.2 X 10(3) and 10(5)/nmole in the SOS Chromotest and mutagenic potencies of 6.3 X 10(4) and 3.7 X 10(7) revertants/nmole in the Salmonella/histidine assay (strain TA98), respectively; the responses were only slightly decreased in nitroreductase-deficient strains. The responses to the two pyrenofurans were increased in the presence of an "activating mixture" but were still lower than that to benzo[a]pyrene. In contrast to benzo[a]pyrene and pyreno[2,1-b]furan (R7692), pyreno[1,2-b]furan (R7490) also gave a response in the absence of an "activating mixture". (5) Compounds with the oxygen heteroatom within the "bay region" gave lower responses than their isomers with the oxygen heteroatom outside the "bay region".

Animals↗

Effect of an umuC mutation on phage lambda induction.

A possible role of the umuC gene product in the induction of the SOS responses was examined. We compared the expression of a genetic fusion, in which gene lacZ, encoding beta-galactosidase in Escherichia coli is under the direct control of the cI repressor from prophage lambda, in a umuC+ strain and in an otherwise isogenic umuC- mutant. We found that two times higher UV doses were required to obtain a similar induction in the umuC+ strain as in the umuC mutant. In addition we showed that, at the same UV dose after a lag period, the specific activity of beta-galactosidase increased more rapidly in the umuC mutant. We suggest that the wild-type umuC gene product participates in the processing of the SOS inducing structures caused by UV irradiation or prevents formation of some of them. This is compatible with a role of the UmuC protein in DNA synthesis past a replication block.

Bacteriophage lambda↗

Protein and mRNA expression of CD56/N-CAM on follicular epithelial cells of the human thyroid.

In order to confirm CD56/N-CAM antigen prevalence in the human thyroid and to compare its expression on thyrocytes and NK cells, an expression of CD56/N-CAM antigen was searched for on isolated thyroid follicular cells and NK cells by flow cytometry. In addition, mRNA for CD56 was searched for in RNA isolated from human thyroid samples and few other organs using dot blot hybridization assay to prove the existence of mechanisms for active synthesis of the protein in question. The isolated cells from the follicular epithelium of 22 various pathological thyroid tissue specimens were examined for the expression of CD56/N-CAM in terms of the percentage of positive cells and the mean fluorescence intensity (MFI). Blood lymphocytes were tested in parallel. The total RNA isolated from thyroid and control tissue specimens was subjected to dot-blot hybridization assay using CD56/N-CAM cDNA probe. All thyroid specimens expressed CD56/N-CAM, but the obtained values differed depending on the tissue examined and the CD56 antibody used. There were no significant differences between the non-malignant thyroid cells of various histology, while cells in the carcinoma group had a much lower MFI, especially the median value. CD56 expression on NK cells from the donors' blood had a homogeneous distribution but the mean and median values of FI were almost three times lower than those on the thyroid cells. Dot blot hybridization came out positive with the RNA isolated from the thyroid specimens and also from the RNA isolated from the tonsil and lymph nodes, but came out negative with the RNA isolated from human and rat kidneys. These results strongly suggest that thyroid follicular epithelial cells express both protein and mRNA of CD56/N-CAM, thus being able to synthesis the relevant antigen. The protein expression seems to be affected by the malignant transformation of the thyroid cells. NK cells have apparently lower CD56/NCAM expression than thyroid cells.

Journal Article↗