175 research outputs found
Pharmacokinetic parameter sets of alfentanil revisited: optimal parameters for use in target controlled infusion and anaesthesia display systems
Background In open TCI and anaesthesia display systems, the choice of pharmacokinetic (PK) parameter sets of opioids is clinically relevant. Accuracy and bias of the PK models may be affected by administration mode and the co-administered hypnotic drug. We retrospectively evaluated the performance of eight PK parameter sets for alfentanil in two data sets (infusion and bolus application). Methods With the dosing history from two studies in orthopaedic patients anaesthetized with propofol or inhalation anaesthetics the alfentanil plasma concentration over time was calculated with eight PK parameter sets. Median absolute performance error (MDAPE), log accuracy, median performance error (MDPE), log bias, Wobble, and Divergence were computed. Mann-Whitney rank test with Bonferroni correction was used for comparison between bolus and infusion data, repeated measures analysis of variance on ranks was used for comparison among parameter sets. Results The parameters by Scott (original and weight adjusted) and Fragen had a MDAPE ≤30% and a median log accuracy <0.15 independent of the administration mode, while MDPE was within ±20% and log bias nearly within ±0.1, respectively. The sets by Maitre and Lemmens were within these limits only in the bolus data. All other parameter sets were outside these limits. Conclusions In healthy orthopaedic patients, the PK parameters by Scott and by Maitre were equally valid when alfentanil was given as repeated boluses. When given as infusion, the Maitre parameters were less accurate and subject to a significant bias. We cannot exclude that the difference between bolus and infusion is partially because of the different hypnotics use
Efficacy and side effects of praziquantel against Schistosoma mansoni in a community of western Côte d'Ivoire
Praziquantel is efficacious against the adult stages of all human schistosome parasites, and has become the drug of choice for morbidity control of schistosomiasis. There is concern that resistance to praziquantel might develop or already exists, and could be further facilitated through new control initiatives relying on large-scale administration of praziquantel. Therefore, monitoring praziquantel efficacy in different epidemiological settings is required. We assessed the efficacy and side effects of praziquantel against Schistosoma mansoni in a rural community of western Côte d'Ivoire. Three consecutive stool specimens from 545 children and adults were examined by the Kato-Katz technique, revealing an overall prevalence of 40.9%. S. mansoni-infected individuals were treated with a single oral dose of praziquantel at 40 mg/kg. The most frequent side effects were abdominal pain, dizziness and diarrhoea. The overall cure rate, assessed 6 weeks post-treatment, was 60.9%. Moderate or heavy infections were only cleared in half or one-third of the individuals, respectively. The total egg count reduction was 61.4%. Infection intensity pre-treatment was significantly associated with age, cure rate, reported diarrhoea and dizziness. Our findings call for additional studies that rigorously evaluate the efficacy of praziquantel against different schistosome species in entire communities, using similarly sensitive diagnostic approaches as employed her
Multiple parasite infections and their relationship to self-reported morbidity in a community of rural Côte d'Ivoire
Background Concomitant parasitic infections are common in the developing world, yet most studies focus on a single parasite in a narrow age group. We investigated the extent of polyparasitism and parasite associations, and related these findings to self-reported morbidity. Methods Inhabitants of 75 randomly selected households from a single village in western Côte d'Ivoire provided multiple faecal specimens and a single finger prick blood sample. The Kato-Katz technique and a formol-ether concentration method were employed to screen faecal samples for Schistosoma mansoni, soil-transmitted helminths and intestinal protozoa. Giemsa-stained blood smears were analysed for malaria parasites. A questionnaire was administered for collection of demographic information and self-reported morbidity indicators. Results Complete parasitological data were obtained for 500/561 (89.1%) participants, similarly distributed among sex, with an age range from 5 days to 91 years. The prevalences of Plasmodium falciparum, hookworms, Entamoeba histolytica/E. dispar, and S. mansoni were 76.4%, 45.0%, 42.2%, and 39.8%, respectively. Three-quarters of the population harboured three or more parasites concurrently. Multivariate analysis revealed significant associations between several pairs of parasites. Some parasitic infections and the total number of parasites were significantly associated with self-reported morbidity indicators. Conclusions Our data confirm that polyparasitism is very common in rural Côte d'Ivoire and that people have clear perceptions about the morbidity caused by some of these parasitic infections. Our findings can be used for the design and implementation of sound intervention strategies to mitigate morbidity and co-morbidit
Enzymatic oligomerization and polymerization of arylamines: state of the art and perspectives
The literature concerning the oxidative oligomerization and polymerization of various arylamines, e.g., aniline, substituted anilines, aminonaphthalene and its derivatives, catalyzed by oxidoreductases, such as laccases and peroxidases, in aqueous, organic, and mixed aqueous organic monophasic or biphasic media, is reviewed. An overview of template-free as well as template-assisted enzymatic syntheses of oligomers and polymers of arylamines is given. Special attention is paid to mechanistic aspects of these biocatalytic processes. Because of the nontoxicity of oxidoreductases and their high catalytic efficiency, as well as high selectivity of enzymatic oligomerizations/polymerizations under mild conditions-using mainly water as a solvent and often resulting in minimal byproduct formation-enzymatic oligomerizations and polymerizations of arylamines are environmentally friendly and significantly contribute to a "green'' chemistry of conducting and redox-active oligomers and polymers. Current and potential future applications of enzymatic polymerization processes and enzymatically synthesized oligo/polyarylamines are discussed
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