Objective: To find out about the experiences of stroke patients concerning their falling ill, their stay in hospital, discharge and homecoming. Design: Qualitative methods using in-depth interviews. Subjects and setting: Nine strategically chosen patients and in five cases near family members were interviewed in their homes four months post stroke and following care at the Stroke Centre, University Hospital of Northern Sweden, Umea°. Results: Three main categories with subcategories were brought to the fore from the interviews: ‘Responsible and implicated’, ’Depersonalized object for caring measures’ and ‘The striving for repersonalization and autonomy’. The patients got the most important insights and understanding about their state and the consequences when they came home. Conclusion: The three main categories that were found mirror the crisis which becoming ill entails and the process gone through when the individual takes control again of his or her life. The patients saw coming home as an important factor for their recovery and rehabilitation. The health care system needs to develop strategies to make use of the power of this attitude with the patients and to use the patients' own milieu in rehabilitation after stroke.

Acylated homoserine lactones (AHLs) regulate a wide variety of phenotypes in Gram-negative bacteria. Most research suggests that AHL-mediated phenotypes are not expressed in populations until late logarithmic phase or stationary phase. Here, we model how the concentration of AHLs inside bacterial cells and in a biofilm changes over time as a function of population growth rate, diffusion of AHLs and the rate of autoinduction. Our theoretical results show that the concentration of AHLs inside a single bacterium (and by implication induction of a phenotype) has a non-trivial behaviour over time, and often exhibits a rapid increase early in population growth. This rapid increase is followed by a plateau, followed by another rise in the concentration of AHLs, to a second plateau. High concentrations of AHLs inside the bacterial cell early in population growth are positively affected by slow diffusion rates out of the cell and the biofilm, slow bacterial growth rates and fast autoinduction. In contrast, fast growth rates, slow autoinduction rates and high diffusion rates result in a high concentration plateau in stationary phase. More generally, the density-dependent nature of AHL regulation can be viewed as a trade-off between factors that dilute intracellular concentrations of AHLs (diffusion out of the cell, cell division), and those that increase concentrations (a slowing or restriction of diffusion or growth, or autoinduction). These results suggest that expression of AHL-mediated phenotypes can occur at relatively low cell densities and low external/environmental AHL concentrations.

Two-dimensional (2-D) crystals of annexin V, grown by specific binding to phosphatidylserine containing planar lipid films, were studied by electron image analysis. Images of negatively stained two-dimensional crystals showed diffraction peaks extending to 11 Angstrom. After correcting lattice distorsions and averaging over several crystalline areas, the resolution of the analysis was extended up to 8 Angstrom. Observed along a direction perpendicular to the membrane plane, the four homologous domains characteristic of annexin V exhibit a noticeable difference in their distribution of protein density. An unambiguous assignment of the domains was possible due to the similar packing of annexin V molecules in the 2-D crystals and in a 3-D crystal form with pseudo-R3 symmetry. The domains I and IV (numbering according to Huber et al., Embo J., 1990, 9, 3867-3874) appear well resolved. On the other hand, the two other domains, II and III, present an almost continuous density, with a protrusion extending outwards the annexin V molecule. In addition, no hydrophilic opening is resolved at the center of the molecule, yet a stain-filled 13-Angstrom structure is present, surrounded by domains I, II, and IV and distant by 5 Angstrom from the center of the molecule. We interpret these structural features as reflecting a conformational change in the annexin V structure resulting from its membrane binding. (C) 1994 Academic Press, Inc.

Trypsin treatment of staphylococcal α-toxin cleaves the molecule into two roughly equally sized parts, which ] results in inactivation of the toxin. Tetragonal arrays of oligomers, closely resembling the native ones, can however be formed on lipid layers. From tilted views of negatively stained crystals a 31) structure to 23 Å resolution has been determined by electron microscopy and image processing. On comparison with the 31) structure of the native ot-toxin (Olofsson et al., J. Mol. Biol. 214, 299–306, 1990) the subdomains are more separated, confirming the differences found when comparing the projection maps (Olofsson et al., J. Struct. Biol. 106, 199–204, 1991). The tryptic cleavage takes place in a postulated hinge region. The results are consistent with the hypothesis that the conformational change required for inducing the membrane permeabilizing property takes place in this region. Furthermore, we present a refined projection map at approximately 10 Å resolution based on the analysis of a large number of crystals using unbending methods.

We report on 20 events of ω− production observed in K−p interactions at 10 GeV/c. A summary of the present world sample is given and new average values of the mass and lifetime of the ω− are calculated. Production and decay characteristics are discussed.