Circular dichroism study of NaSCN effect on conformation of poly-L-lysine

Effects of NaSCN, urea and KCl on alpha, beta and random conformations of poly-L-lysine (PLL) in water at room temperature were examined and compared quantitatively on the basis of the rotational strength of maximal peak by means of circular dichroism (CD) measurement. Alpha and beta helical conformational change of PLL was markedly concentration dependent in both the cases of NaSCN and urea, but not KCl. Among these salts, the distortion potency of millimolar concentrations of NaSCN on both alpha and beta conformations was undoubtedly several hundred times stronger than for the other salts, showing a slightly lesser effect on the alpha conformation as compared with that on the beta helical one, while there was no significant effect on random conformations even in maximal salt concentrations. The concentration required to alter the peptide conformation was substantially smaller for urea than for KCl, but both urea and KCl exhibited more effectiveness on alpha than beta conformation in contrast to NaSCN throughout the respective concentrations.     

Intramuscular loading dose of quinine for falciparum malaria: pharmacokinetics and toxicity.

In a study of intramuscular injection of quinine eight adults with moderately severe falciparum malaria resistant to chloroquine were treated with quinine dihydrochloride, being given a loading dose of 20 mg salt (16.7 mg base)/kg followed by three or four eight hourly maintenance doses of 10 mg salt (8.3 mg base)/kg injected into the anterior thigh. All patients responded to treatment. Fever and parasite clearance times (mean (SD) 60 (23) h and 53 (22) h respectively) were comparable with those obtained with intravenous quinine. The mean peak plasma quinine concentration of 11.0 mg/l (34.4 mu mol/l) [corrected] was reached a median of five hours after administration of the loading dose. In all patients plasma quinine concentrations exceeded the high minimum inhibitory concentration for Plasmodium falciparum malaria prevalent in Thailand within four hours of the start of treatment but did not cause toxicity other than mild cinchonism. When intravenous infusion is not possible an intramuscular quinine loading dose is an effective means of starting treatment in patients with moderately severe falciparum malaria who cannot swallow tablets.     

Recipient competence in F''lac matings of Escherichia coli K-12.

We studied recipient mating ability in the presence of excess F'lac donors. Ninety-five percent of recipients were able to receive F'lac in 30-min matings. Competition between an F'-lac donor and an F'lac traI donor, which mobilized a ColE1 derivative (pML2), showed that each recipient mated with an average of two to three donors in 30 min. Experiments in which the competing donor was added at different times showed that some competition occurred throughout the 30-min mating period, which suggested that aggregate formation was spread over this time.     

The diet of coastal breeding hooded crows corvus corone comix

Three methods of analysis were used to determine the diet of territorial hooded crows at Lough Hyne Marine Reserve, Co Cork, Ireland The regular collection of prey Items from these sites at Lough Hyne was integrated with pellet and stomach analysis to determine diet Intertidal organisms occurred in over 80% of pellets and 43% of stomachs and occupied over 77% of the total wet weight of foods identified in pellets All prey items recovered from drop sites originated from the intertidal habitat, involved either large-sized species or larger individuals of smaller-sized species, and were only dropped during October to February Twenty-five intertidal species were identified but only a few of these species contributed to the bulk of the diet Hooded crows were shown to consume a wide range of intertidal species throughout the year, though the species composition in the diet was seasonally influenced Depletion and weight loss of intertidal molluscs through the winter was shown to have a minimal effect on selection suggesting that prey switching was driven by the birds nutritional requirements     

Leucostasis, an underestimated cause of death in leukaemia

Massive sludging of leukaemic cells in blood vessels is a frequent and often lethal complication of leukaemia. In a retrospective clinicopathological study on the causes of death in 52 patients with acute myeloid leukaemia and myeloproliferative disease, pulmonary leucostasis was found in 40% of the patients. In many of these patients the vessels of the heart, brain and testes were also involved. In search for signs and symptoms specific for leucostasis, the clinical records of the 21 patients with leucostasis (the study group) were compared to those of 20 patients without leucostasis (the control group). Dysfunction of the organs most affected by leucostasis, namely lungs, heart and brain, was found more often in the study group than in the controls, but the combination of unexplained fever with cardiopulmonary and/or central nervous system failure occurred almost exclusively and in half of the patients with leucostasis. Leucostasis occurs predominantly, but not exclusively, in patients with high leucocyte counts, and especially, but again not exclusively, when the leucocyte counts rise sharply.