Numerische Untersuchungen von Parametereinflüssen des dynamischen Systems auf selbsterregte Reibungsschwingungen

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Untersuchung selbsterregter Reibungsschwingungen mit Hilfe eines numerischen Simulationsverfahrens

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Detection of Mycoplasma pulmonis in experimentally infected laboratory rats by 16S rRNA amplification.

Recently, an rRNA-based polymerase chain reaction (PCR) has been developed for the detection of murine mycoplasmas at both the genus and species level (F. J. M. van Kuppeveld, J. T. M. van der Logt, A. F. Angulo, M. J. van Zoest, W. G. V. Quint, H. G. Niesters, J. M. D. Galama, and W. J. G. Melchers, Appl. Environ. Microbiol. 58:2606-2615, 1992). In this study, the diagnostic value of this PCR assay for the detection of Mycoplasma pulmonis in infected rats was studied. For this purpose, 25 Wistar rats were infected intranasally with M. pulmonis strain M72-138 and investigated for the presence of this pathogen by both in vitro isolation and PCR. Five rats were monitored longitudinally by screening of throat swabs at several time points for up to 248 days postinfection. The remaining 20 rats were killed between 3 and 87 days postinfection, and organism recovery from both throat and urogenital tract specimens was attempted. M. pulmonis could be detected in the throat for up to 248 days postinfection but not in the urogenital tract, either by culture or by PCR. PCR proved to be the optimal method for testing throat samples. All samples in which M. pulmonis was detected by culture were also positive by PCR. By PCR, M. pulmonis was also detected in 3.7% of the samples which were culture negative and in 9.9% of the samples from which cultures were overgrown with bacteria. The results of this study demonstrate the suitability of PCR for the detection of mycoplasmal infection in rodents

Detection of mycoplasma contamination in cell cultures by a mycoplasma group-specific PCR.

The suitability of a 16S rRNA-based mycoplasma group-specific PCR for the detection of mycoplasma contamination in cell cultures was investigated. A total of 104 cell cultures were tested by using microbiological culture, DNA fluorochrome staining, DNA-rRNA hybridization, and PCR techniques. A comparison of the results obtained with these techniques revealed agreement for 95 cell cultures. Discrepant results, which were interpreted as false negative or false positive on the basis of a comparison with the results obtained with other methods, were observed with nine cell cultures. The microbiological culture technique produced false-negative results for four cell cultures. The hybridization technique produced false-negative results for two cell cultures, and for one of these cell cultures the DNA staining technique also produced a false-negative result. The PCR may have produced false-positive results for one cell culture. Ambiguous results were obtained with the remaining two cell cultures. Furthermore, the presence of contaminating bacteria interfered with the interpretation of the DNA staining results for 16 cell cultures. For the same reason the hybridization signals of nine cell cultures could not be interpreted. Our results demonstrate the drawbacks of each of the detection methods and the suitability of the PCR for the detection of mycoplasmas in cell cultures

No evidence of mycoplasmas in peripheral blood mononuclear cell fraction of HIV-infected patients.

Contains fulltext : 76528.pdf (publisher's version ) (Open Access)3 p

Die jüngerlatènezeitliche Zentralsiedlung Basel-Gasfabrik im Fokus: Ausgewählte Ergebnisse der interdisziplinären Forschung

Vor 110 Jahren wurde die spätkeltische Siedlung Basel-Gasfabrik in der Nähe des heutigen Voltaplatzes bei Aushubarbeiten zum damaligen Gaswerk entdeckt. Seither fanden in unterschiedlichen Intensitäten mehr als 400 archäologische Rettungsgrabungen statt, die immer in Zusammenhang mit Bauprojekten standen. Mit dem Auslaufen der Feldarbeiten konnten zwei grosse, multidisziplinär konzipierte Auswertungsvorhaben mit den Titeln «Über die Toten zu den Lebenden» (Umgang mit sterblichen Überresten) und «Über den Grubenrand geschaut» (Siedlung) durchgeführt werden. Der wissenschaftliche Bericht beleuchtet schlaglichtartig Resultate der beiden Forschungsprojekte