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The interaction between a small positively charged peptide with a N-terminally linked acyl chain and dipalmitoylphosphatidylcholine-dipalmitoylphosphatidylserine (DPPC-DPPS) lipid membranes has been studied by means of fluorescence resonance energy transfer. Two different lipid compositions were used: a neutral membrane (100 mol% DPPC), and a negatively charged membrane (30 mol% DPPS in DPPC). The fluorescence resonance energy transfer results reveal that the peptide associates with both types of membranes. Furthermore, it is found that the slope of the titration curve for the negatively charged membranes is much steeper than that for the neutral membranes. This indicates a higher binding affinity of the acylated peptide towards negatively charged lipid membranes as compared with neutral lipid membranes.

The structural and dynamical properties of DPPC liposomes containing lipopolymers (PEG-lipids) and charged DPPS lipids have been studied in relation to the lipid membrane interaction of enzymes and peptides. The results suggest that both the lipid membrane structure and dynamics and in particular the appearance of small-scale lipid structures might be of importance for the activity of membrane associated and liposome degrading enzymes as well as for the membrane interaction of acylated peptides. The combined experimental and simulation results are of relevance for a rational development of peptide loaded liposomal drug delivery systems that become destabilized by membrane degrading phospholipase A(2) enzymes, which are found at elevated concentrations at diseased sites.

Plants utilized as traditional medicines in India have been investigated for their ability to inhibit the angiotensin converting enzyme (ACE). In total, 75 species belonging to 42 families have been investigated and new ethnomedical information has been obtained for 41 species. Four species were found to possess a high ACE inhibiting ability and were low in their tannin content.

In a retrospective investigation at the department of Surgery, Frederiksberg Hospital in 1981, the frequency of operations in patients above 80 years old was 3.4% compared to 1.7% in the general population. The total number of operations in the aged group was 183. The object of this investigation was to determine the postoperative mortality and 5-year survival rate in the patients aged 80 years or more. Furthermore, the ability of the patients to stay in their homes was investigated. The patients were divided into a major surgery group and a minor surgery group depending on the extent of the operation. The postoperative mortality var 5.5%. Compared to an age and sex matched control group, only the major surgery group had a higher rate of mortality during the first six postoperative months. Among the patients who were admitted from home, 85% were discharged directly to their homes. At the end of the study period or at the time of death, the percentage of patients staying in old peoples homes was essentially the same as for the rest of the population. It is concluded that the patients aged 80 years or more tolerated surgical trauma relatively well and, that the number of geriatric operations may be anticipated to increase greatly.