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Six various motile Areromonas strains were evaluated with regard to their induction of agglutinin and precipitin production in the serum of immunised rabbits. The results were compared with immunogenic activities of the strains against MAS in carp. A total of 74 Aeromonas sp. strains were involved in carrying out agglutination and precipitation tests. No relationship between agglutinin production and the immunogenic properties of the strains used was determined. In contrast, strains inducing precipitin production against a wide antigen spectrum of non-homologous Aeromonas sp. strains demonstrated the highest immunogenic activity in carp. The immunity of carp derived from vaccinations with the antigens of certain motile Aeromonas strains effectively protected against both homologous and non-homologous strains from this group of microorganisms.
This report presents the data considered by the author as the most important reasons for difficulties in the diagnosis and control of MAS and MAI caused by motile Aeromonas bacteria in fish. The difficulties are chiefly attributed to the properties of these microorganisms, such as their wide variety and variability. Furthermore, numerous studies into certain aspects involved in the pathogenecity of motile Aeromonas in fish have been indicated; however, the comparison of the results of these studies is limited or impossible. The necessity of investigations which may improve diagnostic procedures as well as lead to more applicable, efficient and reasonable methods of the control of MAS and MAI has been stressed.
The purpose of the study was to evaluate an optimum dose of Aeromonas hydrophila and Aeromonas sobria antigens for the vacccination of carp (Cyprinus carpio L.) and to compare the effectiveness of the vaccination with the antigens inactivated with formalin or thermally and given intraperitoneally (ip) or by immersion (imm). The dose was evaluated with the use of formalin antigens. Doses ranging from 3 x 10⁴ to 6 x 10⁸ cells were given by injection and doses of 3 x 10⁵ to 6 x 10⁶ cells/mL of water were administered in bath. Experiments were conducted at 12°C, 16°C, and 23°C ± 1°C . To compare the effectiveness of the antigens inactivated with formalin and thermally the two doses 3 x 10⁸ cells (ip) and 5- 6 x 10⁷cells/mL (imm) were used. The effect of immunisation was evaluated with challenge tests. The relative percentage of health (RPH) and relative percentage of survival (RPS) of fish were calculated. Doses of 3 x 10⁸ cells, and 5-6 x 10⁷ cells/mL given ip and imm, respectively, were considered the most effective irrespective of the water temperature. No marked differences were found between the administration of the antigen by injection and immersion. Fish manifested a significantly higher level of immunity after the administration of formalin antigen in comparison to that following the administration of the antigen inactivated thermally.
A total of 71 Aeromonas strains were isolated in the south of Jiangsu Province China in order to analyze the difference of Aeromonas spp. distribution between diseased fish and water environment. The sequence of 16S rDNA and gyrB demonstrated that the 71 Aeromonas isolates could be divided into 4 species, including A. veronii (55), A. hydrophila (11), A. salmonicida (3) and A. media (2). A. veronii was the most common species isolated from fish and water environment. All Aeromonas isolates were screened for three putative virulence genes, aer, hly and alt. hly was the most common gene among three virulence genes.
Celem niniejszego opracowania było dokonanie przeglądu głównych rodzajów innowacji produktowych i opakowaniowych. Za produkt innowacyjny przyjęto nowy produkt, który w sposób istotny różni się od innych nową techniką produkcji lub nowym sposobem pozycjonowania. W artykule przedstawiono przykłady produktów innowacyjnych w kategorii żywności wzbogacanej w witaminy, składniki mineralne, błonnik, dodatki funkcjonalne, żywności probiotycznej, a także żywności niskoenergetycznej. W końcowej części opracowania przedstawiono wybrane aspekty innowacji opakowaniowych.
Aeromonas organisms are widely distributed in aquatic environments and are also recognized as being pathogens in a variety of animals and humans. The aim of the study was to determine the effect of metal ions (Ca⁺², Cu⁺², Fe⁺², Mg⁺², Zn⁺²) and protease inhibitors (PMSF, EDTA, E-64) on the activity of Aeromonas supernatant caseinase and elastase activity. Sixteen strains of bacteria isolated from MAI/MAS diseased carp, identified as A. hydrophila (n=13) and A. sobria (n=3) were used in the study. Zinc and copper inhibited Aeromonas supernatant caseinase activity, where zinc, copper and iron inhibited elastase activity.
Aeromonas microorganisms normally grow at temperatures between 5°C and 45°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°C, 42°C and 50°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.
A total of 103 strains of Aeromonas spp. isolated from clinical and from environmental samples was compared by using SDS-PAGE of periplasms proteins patterns. Strains isolated from Polish children suffering from gastroenteritis did not appear similar to strains isolated from human living in Hong-Kong. Aeromonas sp. strains did not show a tendency to cluster according to their origin. Our results have demonstrated no species-specifs periplasms protein profiles. A significant protein electrophoretic heterogeneity was observed within the species A. hydrophila, A. hestiarum, A. salmonicida, A. caviae, A. media, and A. vermin biotype sobria.
A study was carried out on the occurrence and activity of chitinolytic planktonic bacteria of Aeromonas sp., Aeromonas hydrophila and Aeromonas salmonicida species, isolated from lake Jeziorak. Among the identified strains decomposing chitin the most abundant were Aeromonas sp.. All the investigated strains showed maximum chitinolytic activity at pH 6.0. An increase in chitinolytic activity was observed that occurred along with temperature growth (10° - 40°C) and colloidal chitin concentration in the medium (0.5 - 2.5%). Their decomposing activity was most intense after a 192 h incubation time. No strain displayed activity after a 48 h incubation time.
The aim of the study was to determine the relationship between serogroups, species, and virulence of Aeromonas sp. Isolates from common carp and rainbow trout were tested for species designation and virulence phenotype and then serogrouped. A total of 558 isolates were tested. The bacteria were identified to species level using PCR-RFLP method. The ß-haemolysin, gelatinase, and caseinase activities were selected for virulence determination. The following species were dominant: A. hydrophila (35), A. bestiarum (103), A. salmonicida (98), A. sobria (101), A. veronii bt. sobria (171), and A. encheleia (30). 380 isolates were classified as virulent for fish. The isolates were serogrouped by agglutination tests according to the scheme of Sakazaki and Shimada. 478 isolates were serologically typeable (they did not show R type antigen or autoagglutination) and for 419 (87.6%) O-antigen was identified. The dominant serogroups among both carp and trout isolates were: O:11, O:16, O:18, O:33, PGO1, and PGO2. Groups O:3, O:6, O:41, PGO4, and PGO6 dominated among carp isolates and groups O:21, O:29, PGO5, and PGO9 were only represented by trout isolates. The relationship between Aeromonas serogroups and species was not found. Of the 15 dominant serogroups, eight groups included only isolates with virulence phenotype and two groups included only non-pathogenic isolates. The remaining groups were represented by virulent, as well as non-virulent isolates. Agglutination test can be used as alternative or complementary method to differentiate pathogenic and non-pathogenic isolates from carp and trout cultured in Poland.
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