No abstract

With the increasing life expectancy, a greater number of elderly patients are being referred to an orthopaedic department to have elective total knee arthroplasty (TKA). Total knee arthroplasty should be considered in the very elderly only after carefully balancing the benefits of surgery against the risks of surgery. The aim of this study was to analyse the mortality, morbidity and cost benefits of elective TKA in a cohort group of the nonagenarian population. Between 1990 and 2006, 42 patients ≥90 years of age had TKA surgery. Patient's notes were retrospectively analysed. A cost-benefit analysis was carried out by comparing the surgical costs against nursing home placement. The mean age at surgery was 90.4 years (range: 90-90.6). There was one major and 11 minor postoperative complications with no immediate or late postoperative deaths. The Knee Society Scores improved from 25 points (range: 8-44) to 81 points (range: 60-95), and the WOMAC Scores improved from 62 points (range: 54-73) to 41 points (range: 34-46) (p < 0.002). The calculated cost-benefit savings for 42 patients at 5 years after TKA was estimated to be £2,746,839. Total knee arthroplasty in the nonagenarian population is safe, beneficial and cost-effective.Résumé L'augmentation de la durée de vie fait qu'une population de plus en plus âgée présente les conditions pour bénéficier d'une prothèse totale du genou. La prothèse totale du genou doit être considérée dans cette population en comparant les bénéfices de la chirurgie et les risques de celle-ci. Le but de cette étude est d'analyser la mortalité, la morbidité, le rapport coût/bénéfice après prothèse totale du genou dans une cohorte de patients nonagénaires. Le rapport coût/bénéfice de ces 42 patients à 5 ans de l'utilisation de la prothèse a été estimé à 2.746.839£. La prothèse totale du genou dans une population de nonagénaire est une intervention sûre et qui permet un rapport coût/ bénéfice positif pour la société.

A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain of Penicillium citrinum has been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition, decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the 40-60% fraction. The optimum temperature for enzyme activity was found in the range of 34-37 degrees C. However, after 30 min at 60 degrees C, the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28 degrees C) for 8 mo. This result in lipase stability suggests an application of lipases from P. citrinum in detergents and other products that require a high stability at room temperature.

Chitin deacetylase (CDA) is an enzyme that catalyzes the hydrolysis of acetamine groups of N-acetyl-D: -glucosamine in chitin, converting it to chitosan in fungal cell walls. In the present study, the activity in batch culture of CDA from six Mucoralean strains, two of them wild type, isolated from dung of herbivores of Northeast Brazil, was screened. Among the strains tested, Cunninghamella bertholletiae IFM 46114 showed a high intracellular enzyme activity of 0.075 U/mg protein after 5 days of culture, and a wild-type strain of Mucor circinelloides showed a high intracellular enzyme activity of 0.060 U/mg protein, with only 2 days of culture, using N-acetylchitopentaose as substrate. This enzyme showed optimal activity at pH 4.5 in 25 mM glutamate-sodium buffer at 50 degrees C, and was stable over 1 h preincubation at the same temperature. The kinetic parameters of CDA did not follow Michaelis-Menten kinetics, but rather Hill affinity distribution, showing probable allosteric behavior. The apparent K(HILL) and Vmax of CDA were 288+/-34 nmol/l and 0.08+/-0.01 U mg protein(-1) min(-1), respectively, using N-acetylchitopentaose as substrate at pH 4.5 at 50 degrees C.

We have assessed the current range of synthetic splinting bandages, using physical and mechanical tests and the subjective opinions of patients, volunteers and orthopaedic staff. Modern bandages have some better properties than standard plaster bandage but do not conform as well, are more expensive, and potentially more hazardous.