Woodland biodiversity management as a tool for reducing human exposure to Ixodes ricinus ticks: a preliminary study in an english woodland.

This paper presents preliminary findings towards developing a UK-specific approach to reducing public exposure to woodland questing Ixodes ricinus tick populations by harnessing existing biodiversity-enhancing woodland ride (i.e., linear non-wooded herbaceous habitat either side of track within woodland) management strategies. This preliminary study in an English woodland firstly assesses whether ecological and environmental factors determine presence and density of questing Ixodes ricinus along woodland rides. Secondly, it sets these findings in the context of woodland ride management guidelines in England in order to understand what impact ride management strategies might have on numbers of questing ticks and tick survival. Nymph and adult I. ricinus presence and abundance were modelled in relation to relevant microclimate and ecological parameter variables. Predictor variables for increased questing nymph abundance included ride orientation, mat depth, occurrence of bracken/bramble and animal tracks, ride/path width, and sward height. Ticks thrive in the ecotonal habitat of a woodland ride, therefore we urge woodland managers to consider the impact of their ride management on ticks and human exposure to ticks. Possible recommendations for mitigating questing I. ricinus in line with biodiversity management guidelines rides are discussed in this paper and include seasonal mowing regimes, management of mulch/mat, and bracken/bramble management through use of scalloped ride edges.

Preventing falls on an elderly care rehabilitation ward.

OBJECTIVE: Comparison of two flooring types--carpet and vinyl--in the bed areas, and two modes of physiotherapy--conventional therapy and additional leg strengthening exercises--in avoiding falls. DESIGN: Randomized 2 x 2 controlled trial. SETTING: Elderly care rehabilitation ward in a community hospital. SUBJECTS: Fifty-four consecutive patients referred for rehabilitation. OUTCOME MEASURES: The incidence of falls, and the change in strength. RESULTS: There were 10 falls on carpet, and only a single fall on vinyl floor covering (relative risk 8.3, 95% confidence interval 0.95-73, p = 0.05). There were four falls in those receiving additional exercise, and seven falls in those receiving only conventional physiotherapy (relative risk 0.21, 95% confidence interval 0.04-1.2, p = 0.12). Fifty-nine per cent of patients were able to complete strength measurements on admission and discharge. In these, handgrip strength improved more in those given additional exercise than conventional physiotherapy (2.1 kg versus -0.3 kg, p < 0.05). CONCLUSION: There is no evidence to support either intervention in preventing falls on a rehabilitation ward, but within this low-powered study, there was a strong trend towards vinyl being superior.

Site-specific conjugation of an enzyme and an antibody fragment.

A site-specific immunoconjugate was prepared between an F(ab')2-like fragment of the monoclonal anti-CEA murine IgG1 A5B7 and a mutant of the dimeric enzyme carboxypeptidase G2 possessing an N-terminal Thr in place of Ala. First an aldehyde was introduced at the N-terminus of the enzyme by mild periodate oxidation and a residue of carbohydrazide was specifically introduced at the C-terminus of the truncated heavy chain of the F(ab')2-like fragment by reverse proteolysis. Then the two modified proteins were conjugated by the formation of a hydrazone bond between the hydrazide and the aldehyde groups. The conjugate obtained retained both enzymic activity and antigen-binding capacity. The antigen-binding capacity was better than that of a similar conjugate made conventionally by random reaction with side chains.

The membrane binding C-terminus of protein A from Staphylococcus aureus affects its cellular localization and causes structural deformation when expressed in Escherichia coli.

Protein A from Staphylococcus aureus is a powerful diagnostic reagent and has several uses in human disease therapy. Expression in non-pathogenic Escherichia coli containing recombinant plasmids coding for this protein has increased its availability, but can reduce the stability of the plasmid-bearing host. By employing immune electron microscopy, we have determined that E. coli containing stable plasmids coding for a truncated version of protein A, without the membrane binding site, secrete this protein through the cytoplasmic membrane and into the periplasmic space, where it accumulates. E. coli containing unstable plasmids, however, which code for the complete protein including the membrane-binding site, target the protein into the cytoplasmic membrane. This accumulation of protein A in the E. coli cytoplasmic membrane inhibits the formation of septa between dividing cells and results in aberrant elongated, multi-chromosomal forms.

Nucleotide sequence analysis of the gene for protein A from Staphylococcus aureus Cowan 1 (NCTC8530) and its enhanced expression in Escherichia coli.

Nucleotide sequence analysis of the gene (spa) for staphylococcal protein A (SPA) from Staphylococcus aureus strain Cowan 1 (NCTC8530) shows that the sequence differs from previously reported SPA nucleotide sequences, especially in the number of repeat units in the cell-wall-binding region of the gene. Dot matrix comparison with streptococcal protein G and the macrophage receptor for the constant fragment (Fc) of immunoglobulins shows a limited but significant homology. The homology to the latter probably identifies the Fc-binding region in the immunoglobulin-binding domains of SPA. Enhanced production of SPA in Escherichia coli was achieved using the lac promoter immediately upstream from the spa gene.