background: the purpose of this study was to find out the frequency of different serotypes of enteropathogenic es­cherichia coli (epec) among healthy/diarrheal cases. methods: a total of 191 strains, 111 from diarrheal and 80 from asymptomatic persons were examined. determination of the epec sero­groups was performed by agglutination tests using polyvalent and monovalent o antiserum. pcr-rflp a...

Ciliary motility is necessary for many developmental and physiological processes in animals. In zebrafish, motile cilia are thought to be required for the deposition of otoliths, which comprise crystals of protein and calcium carbonate, on hair cells of the inner ear. The identity of the motile cilia and their role in otolith biogenesis, however, remain controversial. Here, we show that the ear...

© 2000 American Institute of Physics, S-0031-9228-0001-010-3 E coli is a singlecelled organism that lives in your gut. It is equipped with a set of rotary motors only 45 nm in diameter. Each motor drives a long, thin, helical filament that extends several cell body lengths out into the external medium. The assemblage of motor and filament is called a flagellum. The concerted motion of several f...

For over 30 years the technique of microelectrophoresis has been used to study the surface properties of bacteria and other particles of microscopic size. Since flagella undoubtedly act as cellular surface components, they would be expected to contribute to the electrophoretic behavior of the cells. Likewise, vital motion might be expected to complicate electrophoretic measurements of flagellat...

Tom Pollard is the new president of the prestigious Salk Institute for Biological Studies in La Jolla, California. Until recently, it seemed unlikely that Pollard, who has spent his research career studying how cells move, would make a move himself. He seemed settled at Johns Hopkins University School of Medicine, where he has been for the past nineteen years. But Pollard says it was time for a...

It is generally believed that the last eukaryotic common ancestor (LECA) was a unicellular organism with motile cilia. In the vertebrates, the winged-helix transcription factor FoxJ1 functions as the master regulator of motile cilia biogenesis. Despite the antiquity of cilia, their highly conserved structure, and their mechanism of motility, the evolution of the transcriptional program controll...

The objective of the present study was to analyse the influence of motility on the results of intracytoplasmic sperm injection (ICSI) when testicular spermatozoa are used for microinjection and to correlate this with testicular histology. A total of 197 ICSI treatment cycles (167 couples) was analysed retrospectively in which testicular spermatozoa were used, because of complete azoospermia, fo...

Shadowed motile elements from actinomycetes were observed with an electron microscope. Included were three strains of Actinoplanes, two of Ampullariella, two of Dermatophilus, two of Spirillospora, and four of "Nocardia" turbata. In addition, three types of previously undescribed actionmycetes were represented: (i) the C(4) group (four strains) forming substrate mycelium breaking into motile ro...