Usefulness of a supplementary set of microsatellite DNA markers for parentage testing in cattle.

The aim of the present study was to determine a supplementary set of microsatellite DNA markers to be used in addition to the standard panel of 12 microsatellite markers recommended for parentage testing in cattle. A method has been developed for analysis of 10 loci in a single multiplex PCR reaction and using automated DNA sizing technology in a sequencer, which will enable the additional set of markers to be used for routine pedigree verification. Preliminary analysis showed that the polymorphism of 10 selected markers (PIC and H > 0.5 for 9 loci) and PEc of 99.77% suggest that the microsatellite sequences selected could be useful in cases of disputable parentage where the standard set may prove insufficient, e.g. in closely related animals or those from herds subjected to rigorous selection.

Application of 19 microsatellite DNA markers for parentage control in Borzoi dogs.

The aim of this study was to analyse the polymorphism of 19 microsatellite markers and their usefulness for parentage verification in 28 Borzoi dogs in Poland. The assay involved the following 19 loci: AHTk211, CXX279, REN169018, INU055, REN54P11, INRA21, AHT137, REN169D01, AHTh260, AHTk253, INU005, INU030, FH2848, AHT121, FH2054, REN162C04, AHThl71, REN247M23 and amelogenin. These markers are included in the panel of loci recommended by the ISAG. Amplified PCR products were analysed by an automated sequencer ABI PRISM 3130xl Genetic Analyser. The number of alleles per locus varied from 3 (INU005) to 8 (REN162 and AHT171). Except the INU005 locus, which showed the lowest variation (PIC=0.396, H=0.438), the calculated PIC values exceeded 0.6 and H values ranged from 0.677 (INU055) to as much as 0.84 (REN162). Based on PE(C) it was found that incorrect pedigree in this breed can be excluded with 99.9998% accuracy using DNA analysis.

Near-field scanning optical microscopy in cell biology.

Near-field optics has produced the highest optical resolution that has ever been achieved. The methods involved lie at the interface of far-field optical microscopy and scanned probe microscopy. This article describes the principles behind near-field scanning optical microscopy (NSOM) and highlights its potential in cell biology.

Near-field optical imaging of unstained bacteria: comparison with normal atomic force and far-field optical microscopy in air and aqueous media.

Simultaneous near-field scanning optical and atomic force imaging of bacteria is presented. The bacteria imaged in these studies were unstained. The near-field optical images had excellent signal-to-noise and showed excellent contrast even in these unstained specimens. The images obtained were interpreted in terms of the images that have been obtained by transmission electron microscopy and X-ray imaging. The results show that bacterial near-field optical imaging is going to be a very important tool in the arsenal of the bacteriologist both in terms of understanding the fundamental processes in the life cycle of bacteria with and without cytochemical staining and in terms of clinical diagnostic applications.