Reinnervation of arterial grafts by adrenergic nerves occurs in rats as indicated by increased levels of noradrenaline

To investigate the changes in noradrenaline concentrations in transplanted arterial grafts in rats, 31 female rats 4 to 6 weeks old of the AO/Ks:OC strain were operated on. Femoral arterial grafts were anastomosed to carotid arteries and compared with control femoral segments. Six rats were included in each follow-up group at 0, 1, 4, and 12 weeks, and there were seven rats in the 20-week follow-up group. High-performance liquid chromatography was used to determine the concentrations of noradrenaline. The operation itself decreased noradrenaline concentrations in the grafts to 76 percent of that in the control segments. One week after the operation, the noradrenaline concentration had fallen to 1.7 percent of the control values and started to recover thereafter. One month after the operation, it was 23 percent; at 3 months, it was 31 percent; and at 5 months, it was 43 percent of control values. The decrease from time 0 to 1 week was significant (p = 0.001), as was the increase from 1 week to 20 weeks (p = 0.004). Noradrenaline concentrations had fallen significantly 1 week after the operation and thereafter they increased to levels comparable to those seen in the immediate postoperative period.     

COMPARISON OF IN SITU PHOTOSYNTHETIC ACTIVITY OF EPIPHYTIC,EPIPELIC AND PLANKTONIC ALGAL COMMUNITIES IN AN OLIGOTROPHIC LAKE,SOUTHERN FINLAND1

The photosynthetic activity of different algal communities at the outer edge of an Equisetum fluviatile L. stand in an oligotrophic lake (Pääjärvi, in southern Finland) was investigated. Production by the algal communities was measured simultaneously using a modified ¹⁴C-method, and the results were related to the volume of algae and the available irradiance. The relative production rate (P/B quotient) of phytoplankton was ca. 3 × that of epiphyton and ca. 20 × that of epipelon. Epiphyton productivity remained almost constant although the algal volume varied greatly, suggesting that the surface layer of the algal community was mainly responsible for the photosynthetic activity. In the littoral area (at 1 m depth) primary production/m² of lake surface by phytoplankton, epiphyton and epipelon was similar but in the littoriprofundal area (2–4 m) phytoplankton production was twice that of epipelon. Primary productivity of epiphyton and epipelon/m² of substratum was about equal to phytoplankton productivity/m³ of water at the same irradiance. This relation provided a means of estimating the relative contributions of the different algal communities to the total algal production in the lake.     

Front Cover: Ultraviolet radiation oxidative stress affects eye health (J. Biophotonics 7/2018)

The role of ultraviolet radiation in oxidative stress‐related ocular pathologies is less known than its role in skin cancer. Excessive exposure to ultraviolet radiation is associated with increased oxidative stress in eye tissues, which may promote the development of photokeratitis, cataract, and retinal damages. Children are especially vulnerable: large pupils, transparent ocular media. Efficient everyday protection of the eye should be considered from early age. (Image: with permission from Carl Zeiss Vision International GmbH, Aalen, Germany) Further details can be found in the article by Iliya V. Ivanov, Timo Mappes, Patrick Schaupp, et al. ( e201700377 ).

     

Minor Changes in Vegetation and Carbon Gas Balance in a Boreal Mire under a Raised CO<Subscript>2</Subscript> or NH<Subscript>4</Subscript>NO<Subscript>3</Subscript> Supply

Increasing concentrations of carbon dioxide (CO₂) in the atmosphere or continuous nitrogen (N) deposition might alter the carbon (C) cycle in boreal mires and thus have significant impacts on the development of climate change. The atmospheric impact of the C cycle in mires is twofold: C accumulation attenuates and CH₄ release strengthens the natural greenhouse effect. We studied the effects of an increased supply of CO₂ or NH₄NO₃ on the vegetation and annual CO₂ exchange in lawns of a boreal oligotrophic mire in eastern Finland over a 2-year period. Ten study plots were enclosed with mini-FACE (Free Air Carbon Dioxide Enrichment) rings. Five plots were vented with CO₂-enriched air (target 560 ppmv), while their controls were vented with ambient air; five plots were sprayed with NH₄NO₃, corresponding to a cumulative addition of 3 g N m⁻² a⁻¹, while their controls were sprayed with distilled water only. A raised NH₄NO₃ supply seemed to affect the composition of the moss layer. Raised CO₂ did not affect the vegetation, but gross photosynthesis increased significantly. The change in net CO₂ exchange depended on the annual weather conditions. Our results suggest that C accumulation may increase in wet years and compensate for the warming effect caused by the increase in CH₄ release from this mire. In contrast, a relatively dry and warm growing period favors decomposition and can even make the CO₂ balance negative. Along with the increased CH₄ release under raised CO₂, the decreased C accumulation then increases the radiative forcing of boreal mires. Received 22 October 2001; accepted 13 May 2002.     

Genome Sequence of Lactobacillus crispatus ST1

Lactobacillus crispatus is a common member of the beneficial microbiota present in the vertebrate gastrointestinal and human genitourinary tracts. Here, we report the genome sequence of L. crispatus ST1, a chicken isolate displaying strong adherence to vaginal epithelial cells.Lactobacillus crispatus can persist in the vertebrate gastrointestinal tract and is among the most prevalent species of the Lactobacillus-dominated human vaginal microbiota (2, 9, 13, 14). It belongs to the so-called acidophilus group (3), which has attracted interest because some of its species are important factors in the production of fermented foods (12) and some can, at least transiently, colonize the human host (2, 9, 13, 14). Moreover, some specific strains, mainly L. acidophilus NCFM and L. johnsonii NCC 533, have received prominence as intestinal-health-promoting microbes (4). Although the genomes of seven members of the acidophilus complex have been sequenced to date (12), the genome sequences of L. crispatus and other predominant lactobacillar species in the urogenital flora have mostly remained obscure. Vaginal lactobacilli can have an important role in controlling the health of the host (2, 14). They can, for example, positively influence and stabilize the host''s vaginal microbiota via the production of compounds that are acidic or exert a direct inhibiting action toward pathogenic bacteria (2, 14). In addition to the antimicrobial compounds, the competitive exclusion of pathogens is another mechanism by which the host''s microbiota can be balanced (2). L. crispatus ST1 was originally isolated from the crop of a chicken, and PCR profiling of L. crispatus isolates has verified it to be an abundant colonizer of the chicken crop (6, 8). It also displays a strong protein-dependent adhesion to the epithelial cells of the human vagina and has been shown to inhibit the adhesion of avian pathogenic Escherichia coli (6, 7).The genome was sequenced (18× coverage) using a 454 pyrosequencer with GS FLX chemistry (Roche). The contig order was confirmed and gaps were filled by sequencing PCR fragments from the genomic DNA template using ABI 3730 and Big Dye chemistry (Applied Biosystems). Genomic data were processed using the Staden Package (11) and gsAssembler (Roche). Coding sequences (CDSs) were predicted using Glimmer3 (5) followed by manual curation of the start sites. The remaining intergenic regions were reanalyzed for missed CDSs by using BlastX (1). Annotation transfer was performed based on a BlastP search, followed by Blannotator analysis using default settings (http://ekhidna.biocenter.helsinki.fi/poxo/blannotator) and manual verification. Orthologous groups between the different lactobacillar proteomes were identified using OrthoMCL (10).The genome of L. crispatus ST1 consists of a single circular chromosome 2.04 Mbp in size, with an overall G+C content of 37%, without any plasmids. There are 64 tRNA genes, 4 rRNA operons, and 2 CRISPR loci. Out of the 2,024 predicted CDSs, a putative function was assigned to 77%, whereas 10% of the CDSs were annotated as conserved and 13% as novel. Based on the orthologous grouping, 302 (15%) of the CDSs encoded by ST1 have no detectable homologs in any of the Lactobacillus proteomes published to date.     

Characterization of legumain

The mammalian legumain, also called asparaginyl endopeptidase (AEP), is critically involved in the processing of bacterial antigens for MHC class II presentation. In order to investigate the substrate specificity of AEP in the P1' position, we created a peptide library and digested it with purified pig kidney AEP. Digestion was less efficient only when proline was in the P1' position. Maximum AEP activity was found in lysosomal fractions of different types of antigen presenting cells (APC). When the multiple sclerosis-associated autoantigen myelin basic protein (MBP) was digested with AEP, the immunodominant epitope 83-99 was destroyed. Myoglobin as an alternative substrate was AEP resistant. These results suggest an important, but not necessarily critical role for AEP in lysosomal antigen degradation.