Intake and digestion of horned guan Oreophasis derbianus diets measured in three Mexican zoos

We conducted nutritional analyses of diets offered to and ingested by seven pairs of horned guans (Oreophasis derbianus) in three zoos. Digestibility was calculated with individually housed birds (n=1 at each zoo). Diets offered varied widely among institutions, both in ingredients fed as well as in nutrient composition. Feeding selectivity was evident through differences in composition of diets offered vs. consumed, with fruit (bananas, grape, and/or plantain) and avocado (when offered) highly preferred; green leaves, poultry pellets, and other vegetables comprised lesser proportions of the diet. All facilities fed 2–3X more food than consumed, allowing a great degree of choice of preferred items and potentially consumption of nutritionally imbalanced diets—in particular, mineral constituents. Diets were highly digestible; dry matter (DM) digestion coefficients ranged from 70 to ∼90%; protein digestibility varied from 30 to 80%; fat was >90% digestible. Diet composition was compared with known nutritional requirements of domestic avian species, and feeding recommendations discussed. Despite the wide variability in nutrient composition of diets eaten (i.e. protein 6–10% of DM; fat 2–17% of DM), no overt health problems were noted and all pairs had successfully reproduced on these diets. It is suggested that horned guans may have nutrient requirements more similar to those suggested for other frugivorous birds than values determined for poultry as the physiologic model. Comparisons with native food items, as well as more detailed nutrient balance studies, may provide even better guidelines for captive management of this highly endangered species. Zoo Biol 28:319–330, 2009. © 2009 Wiley-Liss, Inc.     

Tree species richness and composition 15 years after strip clear-cutting in the Peruvian Amazon

Although strip clear-cutting has a long history of use in the temperate zone, it was only recently introduced for timber extraction in tropical rain forests, where it is known as the Palcazú Forest Management System. In this system heterogeneous tropical forests are managed for native gap-dependent timber species by simulating gap dynamics through clear-cutting long, narrow strips every 40 years. As part of an assessment of the sustainability of this system, we evaluated the recovery of tree basal area, species richness, and composition after 15 years of regeneration on two strips (30 × 150 m) clear-cut in 1989 in Jenaro Herrera, Peru. Timber stocking and the effects of silvicultural thinning were assessed in both strips. The strips recovered 58–73% of their original basal area and 45–68% of their original tree species richness. Although both strips recovered more than 50% of their original composition, commercial species had lower basal areas and lower densities than in the forest before the clearing. Pioneer species with high basal areas remained dominant 15 years after the cutting. Silvicultural thinning in 1996 reduced the abundance of pioneer species in both strips, and increased the abundance of commercial species in one of the strips. Half of one strip was harvested by deferment-cut (only commercial trees >30 cm dbh and “other” species >5 cm dbh were cut); regeneration here had greater abundance of commercial species and lower abundance of pioneer species. The low stocking of commercial trees challenges the sustainability claims for this forest management system.     

Rapid recycling of ClC‐2 chloride channels between plasma membrane and endosomes: Role of a tyrosine endocytosis motif in surface retrieval

ClC‐2 chloride channel is present in the brain and some transporting epithelia where its function is poorly understood. We have now demonstrated that the surface channels are rapidly internalised and approximately the 70% of the surface membrane protein recycles after 4‐ to 8‐min internalisation. Endocytosis of ClC‐2 was dependent upon tyrosine 179 located within an endocytic motif. Rapid recycling accompanied by an even faster internalisation could account for the abundant presence of ClC‐2 in intracellular membranous structures. At least a proportion of ClC‐2 resides in lipid rafts. Use of β‐cyclodextrin led to an increase in cell surface channel, but, surprisingly, a decrease in functionally active channels. We suggest that ClC‐2 requires residing in β‐cyclodextrin sensitive clusters with other molecules in order to remain active. Regulation of ClC‐2 trafficking to and within the membrane could be a means of modulating its activity. J. Cell. Physiol. 221: 650–657, 2009. © 2009 Wiley‐Liss, Inc.     

The genus Teliocrinus (Crinoidea,Echinodermata): a key taxon among pentacrinid stalked crinoids

The main characters of the stalked crinoids of the family Pentacrinitidae attributed to the genus Teliocrinus are re‐evaluated from a quantitative study of phenotype variation, new observations on arm and stalk articulations, and observation of ontogenetic trends. All of the specimens collected in the northern Indian Ocean belong to the same species, i.e. Teliocrinus springeri (Clark, 1909). However, two phenotypes living at different depths remain valid as subspecies: Teliocrinus springeri springeri (Clark, 1909) and Teliocrinus springeri liliaceus (Clark, 1909). Teliocrinus shares several ontogenetic trends with Endoxocrinus, especially in nonfunctional brachial articulations and stalk symplexies. Its assignment to the Diplocrininae is confirmed. A discussion of its affinities with pentacrinid fossil genera in which the crown is well preserved suggests that Diplocrininae could have first appeared during the Lower Cretaceous. A shortening of brachitaxes and a paedomorphic trend of stalk symplexies are the main other evolutionary traits. Nonfunctional articulations are frequently found at the paedomorphic pole of the heterochronic gradient, without clear derived characters. Classification of pentacrinids mainly based on such symplesiomorphy or paedomorphic characters must be definitively abandoned. However, in post‐Palaeozoic stalked crinoids the scarcity of well‐preserved fossils, the high frequency of paedomorphy, and convergent adaptive characters makes phylogenetic reconstruction only based on morphological characters very difficult and speculative. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 22–39.     

Comparison of linkage disequilibrium and haplotype diversity on macro- and microchromosomes in chicken

Background

Toll like receptors (TLR) play the central role in the recognition of pathogen associated molecular patterns (PAMPs). Mutations in the TLR1, TLR2 and TLR4 genes may change the ability to recognize PAMPs and cause altered responsiveness to the bacterial pathogens.

Results

The study presents association between TLR gene mutations and increased susceptibility to Mycobacterium avium subsp. paratuberculosis (MAP) infection. Novel mutations in TLR genes (TLR1- Ser150Gly and Val220Met; TLR2 – Phe670Leu) were statistically correlated with the hindrance in recognition of MAP legends. This correlation was confirmed subsequently by measuring the expression levels of cytokines (IL-4, IL-8, IL-10, IL-12 and IFN-γ) in the mutant and wild type moDCs (mocyte derived dendritic cells) after challenge with MAP cell lysate or LPS. Further in silico analysis of the TLR1 and TLR4 ectodomains (ECD) revealed the polymorphic nature of the central ECD and irregularities in the central LRR (leucine rich repeat) motifs.

Conclusion

The most critical positions that may alter the pathogen recognition ability of TLR were: the 9^th amino acid position in LRR motif (TLR1–LRR10) and 4^th residue downstream to LRR domain (exta-LRR region of TLR4). The study describes novel mutations in the TLRs and presents their association with the MAP infection.     

Do synovial biopsies help to support evidence for involvement of innate immunity in the immunopathology of Beh?et's disease?

Behçet's disease is a complex vasculitis of unknown etiology. Abundant neutrophils suggest the involvement of innate immunity. Cytokines are skewed to the T-helper-1 pattern. Few sterile organs are easily accessible for analysis in Behçet's disease. Cañete and coworkers identify inflamed joints as a feasible model and suggest the involvement of innate immunity in Behçet's disease.     

<Emphasis Type="Italic">Demodex gatoi</Emphasis> -associated contagious pruritic dermatosis in cats - a report from six households in Finland

Background  

Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation.     

Protein tyrosine phosphatases regulate arachidonic acid release, StAR induction and steroidogenesis acting on a hormone-dependent arachidonic acid-preferring acyl-CoA synthetase

The activation of the rate-limiting step in steroid biosynthesis, that is the transport of cholesterol into the mitochondria, is dependent on PKA-mediated events triggered by hormones like ACTH and LH. Two of such events are the protein tyrosine dephosphorylation mediated by protein tyrosine phosphatases (PTPs) and the release of arachidonic acid (AA) mediated by two enzymes, ACS4 (acyl-CoA synthetase 4) and Acot2 (mitochondrial thioesterase). ACTH and LH regulate the activity of PTPs and Acot2 and promote the induction of ACS4. Here we analyzed the involvement of PTPs on the expression of ACS4. We found that two PTP inhibitors, acting through different mechanisms, are both able to abrogate the hormonal effect on ACS4 induction. PTP inhibitors also reduce the effect of cAMP on steroidogenesis and on the level of StAR protein, which facilitates the access of cholesterol into the mitochondria. Moreover, our results indicate that exogenous AA is able to overcome the inhibition produced by PTP inhibitors on StAR protein level and steroidogenesis. Then, here we describe a link between PTP activity and AA release, since ACS4 induction is under the control of PTP activity, being a key event for AA release, StAR induction and steroidogenesis.     

Global and local mechanisms sustain axonal proteostasis of transmembrane proteins

The control of neuronal protein homeostasis or proteostasis is tightly regulated both spatially and temporally, assuring accurate and integrated responses to external or intrinsic stimuli. Local or autonomous responses in dendritic and axonal compartments are crucial to sustain function during development, physiology and in response to damage or disease. Axons are responsible for generating and propagating electrical impulses in neurons, and the establishment and maintenance of their molecular composition are subject to extreme constraints exerted by length and size. Proteins that require the secretory pathway, such as receptors, transporters, ion channels or cell adhesion molecules, are fundamental for axonal function, but whether axons regulate their abundance autonomously and how they achieve this is not clear. Evidence supports the role of three complementary mechanisms to maintain proteostasis of these axonal proteins, namely vesicular transport, local translation and trafficking and transfer from supporting cells. Here, we review these mechanisms, their molecular machineries and contribution to neuronal function. We also examine the signaling pathways involved in local translation and their role during development and nerve injury. We discuss the relative contributions of a transport‐controlled proteome directed by the soma (global regulation) versus a local‐controlled proteome based on local translation or cell transfer (local regulation).