New tetromycin derivatives with anti-trypanosomal and protease inhibitory activities

Four new tetromycin derivatives, tetromycins 1-4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001(T) cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV M(pro), and PL(pro). The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteases with K(i) values in the low micromolar range.     

Exploring the potential of intersectoral partnerships to improve the position of farmers in global agrifood chains: findings from the coffee sector in Peru

Despite their recent proliferation in global agricultural commodity chains, little is known about the potential of intersectoral partnerships to improve the position of smallholder farmers and their organizations. This article explores the potential of partnerships by developing a conceptual approach based on the sustainable livelihoods and linking farmers to market perspectives, which is applied in an exploratory study to six partnerships in the coffee sector in Peru. It is concluded that partnerships stimulate the application of standards to receive market access and therefore emphasize human capital development of farmers to facilitate certification. By transferring knowledge to farmers, partnerships present a new source of technological change, which, in combination with certification, holds potential for improved environmental management and price premiums for producers. However, the emphasis on certification results in a comparatively narrow target group of farmers and is associated with high financial burdens for producer organizations. At the same time, other assets of producer organizations are often not strengthened sufficiently for them to operate successfully without further external support. This suggests that preparing producers for certification is prioritized over empowering organizations toward self-dependence.     

Bioeconomic modeling of mixed Norway spruce—European beech stands: economic consequences of considering ecological effects

The study provides an improved bioeconomic model of mixed-species stands in order to test the economic consequences of tree species mixtures composed of spruce (Picea abies [L.] Karst.) and beech (Fagus sylvatica L.), when the impact of mixing tree species on stand resistance against hazards is considered. We used survival probabilities of spruce in mixed- and mono-species stands derived by Griess et al. (For Ecol Manag 267:284–296, 2012) to expand an existing bioeconomic model by Knoke and Seifert (Ecol Model 210:487–498, 2008). Monte-Carlo simulations showed the highest average net present value (sum of all net revenues during one rotation period discounted by 2 %) for spruce stands with a small beech admixture of 7 % of total stems. The net present value of this mixed stand type was 8 % higher than that reached with a spruce monoculture, while risk—measured as standard deviation of net present value—was 18 % lower than that of a pure spruce stand. A mixed stand with 51 % beech led to a decrease of 23 % of the average net present value when compared to a spruce monoculture. However, the stabilizing effect of this high proportion of beech trees on spruce together with general economic diversification effects (as a result from low correlation of hazard and market risks of both tree species) reduced the standard deviation of the net present value by 55 %. Generally, an intensive species mixture in groups, with interactions between species throughout the stand, led to higher net present values and lower risks when compared to mixtures of identical proportions in large homogenous blocks without species interactions. For calculating survival probability, data from Rhineland-Palatinate were used, for modeling growth, data were based on information gained in Bavaria. It can be assumed that susceptibility toward windthrow was underestimated with respect to Bavarian conditions or growth was overestimated with respect to Rhineland-Palatinate conditions. This narrows the explanatory power of the study at hand and—once again—highlights the importance of a standardization of inventory processes all over Europe. Still the strong potential of mixing species is proven by the results. The hypothesis, derived from simpler, more traditional bioeconomic models that mixed-species stands are economically inferior to mono-species stands, could therefore be rejected. Of particular relevance to practicing foresters is the result that even mild admixtures may lead to substantial positive economic consequences. With relatively small initial investments then, a considerable increase in efficiency can be expected. This finding makes the admixture of at least small proportions interesting for the privately owned forest sector.     

Antimicrobial peptides: agents of border protection for companion animals

Over the past 20 years, there have been significant inroads into understanding the roles of antimicrobial peptides in homeostatic functions and their involvement in disease pathogenesis. In addition to direct antimicrobial activity, these peptides participate in many cellular functions, including chemotaxis, wound healing and even determination of canine coat colour. Various biological and genetic approaches have helped to elucidate the role of antimicrobial peptides with respect to innate immunity and host defense. Associations of antimicrobial peptides with various skin diseases, including psoriasis, rosacea and atopic dermatitis, have been documented in humans. In the longer term, therapeutic modulation of antimicrobial peptide expression may provide effective new treatments for disease. This review highlights current knowledge about antimicrobial peptides of the skin and circulating leukocytes, with particular focus on relevance to physiology and disease in companion animals.     

Zu Ernährung und Beutefang einiger Weberknechte

Ohne Zusammenfassung     

Clinical and pathological findings in a HERDA-affected foal for 1.5 years of life

A Quarter horse filly bred from two horses affected with HERDA (hereditary equine regional dermal asthenia) was observed clinically and its skin histologically for the 1.5 years of its life. Severe signs of the disease did not manifest until 1.5 years of age, and were not temporally related to saddling. Histological comparison to an age-, breed- and sex-matched control did not show any consistent diagnostic features. Monitoring of the proband substantiated previous reports of (i) the autosomal recessive nature of the disease, (ii) mares affected with HERDA being able to foal without damage to the skin or reproductive tract, (iii) HERDA foals appearing phenotypically normal throughout the first year of life, and (iv) demonstrated that histological interpretation of skin specimens from grossly normal skin may be insufficient to differentiate HERDA-affected horses from controls.