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Background. In rat, the first 18-24 h after partial hepatectomy (PH) are characterized by an acute-phase reaction, after which liver regeneration predominates. Interleukin-6 (IL-6) induces the iron hormone hepcidin, which blocks iron uptake and may compromise iron uptake in the growing liver. The expressions of hepcidin and the iron-regulatory pathway of hepcidin gene expression during the late phase of liver regeneration are unknown. Aim. To characterize the expression pattern of hepcidin and the iron-sensing pathway of hepcidin regulation during liver regeneration. Methods. Rats were subjected to PH or sham operation. Liver weights, number of S-phase nuclei, and serum levels of iron and IL-6 were determined. Messenger-RNA levels of hepcidin, ferritin, hemojuvelin, transferrin receptor 1 and 2, HFE, divalent metal transporter 1, ferroportin, and ceruloplasmin were determined with qPCR at different time points. Protein levels of STAT3 and SMAD4 were determined with western blot. Results. During the acute-phase response, IL-6 release induced STAT3 protein and hepcidin mRNA, whereas mRNA levels of proteins in the iron-sensing pathway (HFE, hemojuvelin, and transferrin receptor 2) decreased. The mRNA levels of proteins involved in cellular iron uptake were increased and cellular iron export unchanged. During liver regeneration >24 h after PH, gene expressions in the iron-sensing pathway were continuously suppressed and hepcidin mRNA levels declined 3-7 days after surgery. Conclusions. Hepcidin gene expression peaks during the acute-phase response, but a sustained down-regulation of the iron-sensing pathway of hepcidin regulation gradually reduces hepcidin gene expression until regeneration is complete, thereby promoting iron mobilization to the regenerating liver. [ABSTRACT FROM AUTHOR]

Planning instruments have to be consistent with the underlying values of the forest owners to have an influence on their management activities. The aims of the present study were to identify different types of Swedish forest owners, to quantify their objectives and to validate a previous, qualitative study of the objectives of the small-scale forest owners. A survey was conducted and forest owners were classified by means of cluster analysis into five types: the “economist”, the “conservationist”, the “traditionalist”, the “multiobjective owner” and finally the “passive owner”. Significant factors characterizing these owners are presented and discussed. The results showed that clear subgroups of forest owners can be differentiated by their objectives and confirm recent studies suggesting that a sole emphasis on economic benefits is not desirable from the forest owners’ point of view. The findings should give a better understanding of the behaviour of the small-scale forest owners and provide a basis for further research, counselling and development of forest policy. [ABSTRACT FROM AUTHOR]

A model optimizing single-tree growth in young stands of Scots pine (Pinus sylvestris L.) was used for economic analyses of pruning. Normal sawlogs, butt-logs for slice veneer and for through-and-through sawing and pulpwood were cross-cut. According to the analyses, a dense, naturally regenerated stand should, preferably without pruning, be thinned initially from below for reduction of stem number followed by thinnings from above to produce high-grade timber. A less dense naturally regenerated stand and a stand planted in dense spaces (1.5-2.5 m) can be pruned followed by a similar cutting programme. Owing to high pruning costs and a long period of healing-over, a stand with larger spacing ( >2.5 m) is not suitable for high-grade timber production and should be thinned from above twice followed by an early final cut. The conclusions are drawn under assumptions of average levels during the 1990s of timber prices, management costs and discount rate. [ABSTRACT FROM AUTHOR]

Ten halogenated aliphatic hydrocarbons have been investigated for subacute toxic effects in rats. The biological testing involved 248 measurements for each one of the compounds; the resulting data contain information regarding effects on clinical chemistry and hematology patterns, as well as data on changes in total body weight and weights of specific internal organs. Principal component analysis was used to analyze the multivariate response data. This multivariate biological profiling showed that, with the current experimental protocol, primarily four compounds could be identified as having biological profiles deviating from the others. These compounds were trichloromethane, 1,2‐dichloroethane, 1,1,2,2‐tetrachloroethane and 2‐chloropropane. By identifying compounds with deviating/unique biological profiles, the present work forms a basis for future quantitative structure‐activity relationships analysis of these data. [ABSTRACT FROM PUBLISHER]