The poor health of deep-water species in the context of fishing activity and a warming climate: will populations of Molva species rebuild or collapse?

Many deep-water fish populations, being K-selected species, have little resilience to overexploitation and may be at serious risk of depletion as a consequence. Sea warming represents an additional threat. In this study, the condition, or health, of several populations of common ling (Molva molva), blue ling (Molva dypterygia) and Mediterranean or Spanish ling (Molva macrophthalma) inhabiting different areas in the North Atlantic and the Mediterranean was evaluated, to shed light on the challenges these deep-water species are facing in the context of fishing activity and a warming climate. The data on the condition of Molva populations which are analysed here have been complemented with data on abundance and, for the southernmost species (Mediterranean ling), with two other health indicators (parasitism and hepato-somatic index). Despite some exceptions (e.g., common ling in Icelandic waters), this study shows that the condition of many populations of Molva species in the northeastern Atlantic and the Mediterranean Sea has worsened, a trend which, in recent decades, has usually been found to be accompanied by a decline in their abundance. In addition, the poor health status of most populations of common ling, blue ling and Mediterranean ling considered in this analysis points to a lower sustainability of these populations in the future. Overall, the health status and abundance of Molva populations in the northeastern Atlantic and the Mediterranean suggest that only some populations located in the North Atlantic may be able to rebuild, whereas the populations in southern North Atlantic and the Mediterranean, which are probably most at risk from sea warming, are facing serious difficulties in doing so. In the context of fisheries and global warming, this study's results strongly indicate that management bodies need to consider the health status of many of the populations of Molva species, particularly in southern European waters, before implementing their decisions.     

Understanding the key characteristics and challenges of pine barrens restoration: insights from a Delphi survey of forest land managers and researchers

Pine barrens are open‐canopy ecological communities once prevalent on sandy soils across the northern Great Lakes Region of the United States and Canada, though fire suppression and plantation forestry have now reduced them to a few isolated areas. Efforts to restore pine barrens are underway on some public lands, but lack of knowledge on the social and ecological issues and challenges that affect these projects impedes fuller progress. As a precursor to designing a public preference survey for pine barrens restoration, we sought input from those with expert knowledge about pine barrens. Using a three‐round modified Delphi survey, forest land managers and researchers identified the key characteristics of pine barrens and important current and future management challenges. Key characteristics were related to fire, landscape structure, plant and animal species, soils, and social themes. Current and future challenges were related to landscape, invasive species, social, economic, climate change, and science themes. Four social issues (education, fire acceptance, fire risk, aesthetics) were rated among the top current challenges but none of them maintained prominence as future challenges. Potential explanations for this shift are that the experts felt these social concerns would be resolved in time or that other issues, such as development pressures and budgets for carrying out restoration, would become greater future challenges. Our approach can be used by managers and researchers to better understand the ecosystems they seek to restore and to communicate with public stakeholders about restoration efforts.     

R-Spondin1 enhances wnt signaling and decreases weight loss in short bowel syndrome zebrafish

BackgroundR-spondins, including R-spondin 1 (RSPO1), are a family of Wnt ligands that help to activate the canonical Wnt/β-catenin pathway, which is critical for intestinal epithelial cell proliferation and maintenance of intestinal stem cells. This proliferation underpins the epithelial expansion, or intestinal adaptation (IA), that occurs following massive bowel resection and short bowel syndrome (SBS). The purpose of this study was to identify if recombinant human RSPO1 (rhRSPO1) could be serially administered to SBS zebrafish to enhance cellular proliferation and IA.MethodsAdult male zebrafish were assigned to four groups: sham + PBS, SBS + PBS, sham + rhRSPO1, and SBS + rhRSPO1. Sham fish had a laparotomy alone. SBS fish had a laparotomy with distal intestinal ligation and creation of a proximal stoma. Fish were weighed at initial surgery and then weekly. rhRSPO1 was administered post-operatively following either a one- or two-week dosing schedule with either 3 or 5 intraperitoneal injections, respectively. Fish were harvested at 7 or 14 days with intestinal segments collected for analysis.ResultsRepeated intraperitoneal injection of rhRSPO1 was feasible and well tolerated. At 7 days, intestinal epithelial proliferation was increased by rhRSPO1. At 14 days, SBS + rhRSPO1 fish lost significantly less weight than SBS + PBS fish. Measurements of intestinal surface area were not increased by rhRSPO1 administration but immunofluorescent staining for β-catenin and gene expression for cyclin D1 was increased.ConclusionsIntraperitoneal injection of rhRSPO1 decreased weight loss in SBS zebrafish with increased β-catenin + cells and cyclin D1 expression at 14 days, indicating improved weight maintenance might result from increased activation of the canonical Wnt pathway.     

Growth Response of Coyote Willow (Salix exigua) Cuttings in Relation to Alluvial Soil Texture and Water Availability

A common approach to re‐establishing cottonwood–willow habitat along regulated rivers is through installing dormant, rootless cuttings, yet there is little published information exploring floodplain characteristics that optimize growth of southwestern riparian willows planted in this manner. The goal of this project was to evaluate relationships between growth attributes of Salix exigua and soil texture and soil water availability. Monitoring plots were established in five willow swales planted with dormant S. exigua cuttings along the banks of the Middle Rio Grande in central New Mexico. Data analysis revealed significantly higher aerial cover, height, and stem density for S. exigua plants installed in plots with intermediate levels (15–25%) of fine textured soils distributed through the soil profile. Similar relationships were found in relation to soil water availability. Regression analysis of percent fines and available water at different depth increments provided limited explanation of variability in willow growth attributes at different plots. Findings indicate that S. exigua plants established from cuttings can achieve heights and aerial cover values similar to naturally established willow bars if the floodplain soil profile contains intermediate levels of fine textured soils and the maximum depth to groundwater is within 1.5 m of the ground surface. Where sites are dominated by coarse sand, S. exigua growth may be improved if maximum depth to groundwater is within 1 m of the ground surface.     

Experimental and modelling studies of drought‐adaptive root architectural traits in wheat (Triticum aestivum L.)

Abstract

This paper presents an interdisciplinary approach to crop improvement that links physiology with plant breeding and simulation modelling to enhance the selection of high‐yielding, drought‐tolerant varieties. In a series of field experiments in Queensland, Australia, we found that the yield of CIMMYT wheat line SeriM82 ranged from 6% to 28% greater than the current cultivar Hartog. Physiological studies on the adaptive traits revealed that SeriM82 had a narrower root architecture and extracted more soil moisture, particularly deep in the profile. Results of a simulation analysis of these adaptive root traits with the cropping system model APSIM for a range of rain‐fed environments in southern Queensland indicated a mean relative yield benefit of 14.5% in water‐deficit seasons. Furthermore, each additional millimetre of water extracted during grain filling generated an extra 55 kg ha^?1 of grain yield. Further root studies of a large number of wheat genotypes revealed that wheat root architecture is closely linked to the angle of seminal roots at the seedling stage – a trait which is suitable for large‐scale and cost‐effective screening programmes. Overall, our results suggest that an interdisciplinary approach to crop improvement is likely to enhance the rate of yield improvement in rain‐fed crops.     

Background levels of hydrogen cyanide in human breath measured by infrared cavity ring down spectroscopy

Hydrogen cyanide (HCN) in breath has been suggested as a diagnostic tool for cyanide poisoning and for cyanide-producing bacterial infections. To distinguish elevated levels of breath HCN, baseline data are needed. Background levels of HCN were measured in mixed exhaled air from 40 healthy subjects (26 men, 14 women, age 21–61 years; detection limit: 1.5?ppb; median: 4.4?ppb; range <1.5–14?ppb) by near-infrared cavity ring down spectroscopy (CRDS). No correlation was observed with smoking habits, recent meals or age. However, female subjects had slightly higher breath levels of HCN than male subjects. CRDS has not previously been used for this purpose.     

Adhesion molecules in subjects with COPD and healthy non-smokers: a cross sectional parallel group study

Background

The aim of the study was to investigate how the expression of adhesion molecules changes as neutrophils migrate from the circulation to the lung and if these changes differ between non-smoking subjects and smokers with and without COPD.

Methods

Non-smoking healthy subjects (n=22), smokers without (n=21) and with COPD (n=18) were included. Neutrophils from peripheral blood, sputum and bronchial biopsies were analysed for cell surface expression of adhesion molecules (CD11b, CD62L, CD162). Serum, sputum supernatant and BAL-fluid were analysed for soluble adhesion molecules (ICAM-1, -3, E-selectin, P-selectin, VCAM-1, PECAM-1).

Results

Expression of CD11b was increased on circulating neutrophils from smokers with COPD. It was also increased on sputum neutrophils in both smokers groups, but not in non-smokers, as compared to circulating neutrophils.Serum ICAM-1 was higher in the COPD group compared to the other two groups (p<0.05) and PECAM-1 was lower in smokers without COPD than in non-smoking controls and the COPD group (p<0.05). In BAL-fluid ICAM-1 was lower in the COPD group than in the other groups (p<0.05).

Conclusions

Thus, our data strongly support the involvement of a systemic component in COPD and demonstrate that in smokers neutrophils are activated to a greater extent at the point of transition from the circulation into the lungs than in non-smokers.     

The cell death protease Kex1p is essential for hypochlorite-induced apoptosis in yeast

Following microbial pathogen invasion, the human immune system of activated phagocytes generates and releases the potent oxidant hypochlorous acid (HOCl), which contributes to the killing of menacing microorganisms. Though tightly controlled, HOCl generation by the myeloperoxidase-hydrogen peroxide-chloride system of neutrophils/monocytes may occur in excess and lead to tissue damage. It is thus of marked importance to delineate the molecular pathways underlying HOCl cytotoxicity in both microbial and human cells. Here, we show that HOCl induces the generation of reactive oxygen species (ROS), apoptotic cell death and the formation of specific HOCl-modified epitopes in the budding yeast Saccharomyces cerevisiae. Interestingly, HOCl cytotoxicity can be prevented by treatment with ROS scavengers, suggesting oxidative stress to mediate the lethal effect. The executing pathway involves the pro-apoptotic protease Kex1p, since its absence diminishes HOCl-induced production of ROS, apoptosis and protein modification. By characterizing HOCl-induced cell death in yeast and identifying a corresponding central executor, these results pave the way for the use of Saccharomyces cerevisiae in HOCl research, not least given that it combines both being a microorganism as well as a model for programmed cell death in higher eukaryotes.