Some precursors of glycogen in Ascaris suum females

Intensity of incorporation of the labelled carbon from glucose, glucosamine and leucine into the glycogen of somatic cells and reproductive organs of Ascaris suum females has been studied. Glucose was most intensively incorporated into the growing oocytes and into the uterine epithelial cells, whereas its incorporation into muscle glycogen was found to result in lowest rates. Radiocarbons from glucosamine and leucine were incorporated into tissue glycogen of female worms much less than glucose. Incorporation of isotopes into glycogen of the eggs depended on the formation of their primary shells. The ways of incorporation of isotopes into glycogen of the eggs after formation of all the shell layers are discussed.     

The effect of lead on photosynthesis, as determined by photoacoustics in Synechococcus leopoliensis (Cyanobacteria)

The effect of lead on photosynthetic light storage efficiency was measured by the photoacoustic method. The advantage of this method is in its directness, since the signal obtained by a hydrophone is proportional to that fraction of light energy that is dissipated as heat. This increases as less energy is stored photochemically if the photosynthetic apparatus is damaged. Cells of shape Synechococcus leopoliensis (Cyanobacteria) were grown in medium containing lead in concentrations of 0, 25, 50, 100, and 200 ppm. To avoid the co-precipitation of lead and phosphorus as lead phosphate, phosphorus was omitted from the media used during weeklong exposure to lead. Both chlorophyll concentration and photosynthetic energy storage efficiency decreased with time and with lead concentration. Reduction of photosynthesis progressed with time and increased with lead concentration, reaching up to 80% at the highest lead concentration after seven days.     

Interactions between commensal fungi and the C-type lectin receptor Dectin-1 influence colitis

The intestinal microflora, typically equated with bacteria, influences diseases such as obesity and inflammatory bowel disease. Here, we show that the mammalian gut contains a rich fungal community that interacts with the immune system through the innate immune receptor Dectin-1. Mice lacking Dectin-1 exhibited increased susceptibility to chemically induced colitis, which was the result of altered responses to indigenous fungi. In humans, we identified a polymorphism in the gene for Dectin-1 (CLEC7A) that is strongly linked to a severe form of ulcerative colitis. Together, our findings reveal a eukaryotic fungal community in the gut (the "mycobiome") that coexists with bacteria and substantially expands the repertoire of organisms interacting with the intestinal immune system to influence health and disease.     

Influence of Ascaridia-galli invasion on amino acid, protein and aminotransferase (GOP, GTP) levels and activities in chickens]

A negative influence of the helminths Ascaridia galli on the level of free plasma amino acids and aspartate and alanine aminotransferase activities was demonstrated in the host chick serum. Despite the above negative influence single experimental Ascaridia galli invasion failed to influence the serum protein level or weight increments in chicks. At low invasion intensity the experimental chicks were able to compensate for the pathogenic effect of the helminth Ascaridia galli, manifested by decreased amino acid and aminotransferase activity levels, provided that they were given a full-value and the chicks were kept under suitable zoohygienical conditions.     

Histologic changes in ruptured canine cranial cruciate ligament

OBJECTIVES: To determine changes to the cells and collagenous and amorphous extracellular matrix (ECM) structure in ruptured canine cranial cruciate ligaments (CCL). STUDY DESIGN: Prospective clinical study. ANIMALS: CCL specimens obtained from 29 dogs with ruptured CCL and 6 young dogs with intact CCL. METHODS: Ligament fibroblast number density and phenotype were determined in the core and epiligamentous regions. ECM birefringence and crimp structure in the core region were also studied. RESULTS: Loss of fibroblasts from the core region of ruptured CCL was seen (P <.001), whereas, in the epiligamentous region, cell number densities were similar in ruptured and intact CCL (P =.7). In ruptured CCL, numbers of typical ligament fibroblasts (fusiform and ovoid cells) were decreased, and numbers of cells exhibiting chondroid transformation (spheroid cells) were increased in the core region (P <.001). Expansion of the volume of the epiligamentous region was also seen, although bridging scar tissue was not seen between the ends of ruptured CCL. The structure of the ECM collagen in the core region was extensively disrupted in ruptured CCL. This was, in part, because of decreased birefringence and elongation of the crimp in the remaining collagen fibers when compared with intact CCL (P <.01). CONCLUSIONS: Extensive alterations to the cell populations and collagenous ECM structure were seen in ruptured CCL. Although a proliferative epiligamentous repair response was seen in ruptured CCL, there was a lack of any bridging scar between the ruptured ends of the CCL. CLINICAL RELEVANCE: The cellular and ECM changes in ruptured CCL that we have described appear to result from the cumulative effects of remodeling and adaptation to mechanical loading and microinjury. Treatment of early cruciate disease in dogs will need to inhibit or reverse these progressive changes to CCL tissue, which are directly associated with partial or complete structural failure of the CCL under conditions of normal activity.     

Reconstitution and phosphorylation of chloride channels from airway epithelium membranes

Airway epithelial chloride secretion is controlled by the apical-membrane chloride permeability. Purified apical-membrane vesicles from bovine tracheal epithelium have now been shown to contain functional chloride channels by using the planar-bilayer technique. Three types of chloride channels were observed; a voltage-dependent, calcium-independent, 71-picoSiemen (in 150 mM NaCl) channel accounted for more than 80 percent of the vesicular chloride conductance and was under strict control of phosphorylation. The channel underwent a fast rundown in less than 2 to 3 minutes of recording, and reactivation required in situ exposure to a phosphorylating "cocktail" containing the catalytic subunit of the adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase. Mean open time and open probability were increased after phosphorylation, whereas slope conductance remained unchanged. Thus, metabolic control of tracheal chloride single channels can now be studied in vitro.     

Effects of depth and eutrophication on the zooxanthella clades of Stylophora pistillata from the Gulf of Eilat (Red Sea)

• 1. The symbiotic association between corals and zooxanthellae has been a major contributing factor in the success of reef‐building corals.
• 2. The diversity of zooxanthellae harboured in the hermatypic coral Stylophora pistillata in the Gulf of Eilat (Aqaba), northern Red Sea, was investigated on the basis of the length and sequence variation of the 18S small subunit ribosomal DNA. Of several clades found worldwide, only clades A and C were found to be associated with this coral species in the Gulf.
• 3. No correlation between the pink and brown colour morphs of the coral S. pistillata and the zooxanthella clade was found. Shallow‐water colonies (5 m) harbour clade A while deeper‐water colonies (17 m) harbour either clade A or C. This coral is a brooding species that associates with different zooxanthellae at different depths.
• 4. Eutrophication from fish farms did not affect clade identity associated with Stylophora.

Copyright © 2008 John Wiley & Sons, Ltd.