Predation by the isopod Saduria entomon on the amphipods Monoporeia affinis and Pontoporeia femorata: experiments on prey vulnerability

Summary Predation by Saduria entomon on the depositfeeding amphipods Monoporeia (=Pontoporeia) affinis and Pontoporeia femorata was studied in laboratory experiments. Prey vulnerabilities were compared in singleprey treatments and in mixed-prey treatments, where the proportions of the two species were varied at one total density. In a pilot experiment, P. femorata was the more vulnerable prey, both in single-prey and mixed-prey treatments. In later experiments, the amphipod species were equally vulnerable in single-prey treatments, while in mixed-prey treatments Saduria preyed preferentially on M. affinis, even when this prey was rare, i.e. it did not switch. We suggest that the different result in the later experiments may have been due to a change in the search mode of the isopods.     

Endotoxins from Cyanobacteria and Gram-negative Bacteria as the Cause of an Acute Influenza-like Reaction after Inhalation of Aerosols

Endotoxins (lipopolysaccharides) in aerosols, originating from cyanobacteria and gram-negative bacteria, were the likely etiological agent behind outbreaks of a transient, flu-like syndrome, described from four Scandinavian towns and Harare, Zimbabwe. The syndrome with fever, malaise, muscle pains, tightness of the chest and respiratory-tract symptoms, also known as toxic pneumonitis, occurred 1.5–6 hours after taking a bath or shower. The outbreaks were associated with mass developments of cyanobacteria in the drinking water reservoirs. Cyanobacterial cells and elevated levels of endotoxins were detected in the Harare tap water when human subjects reported symptoms. In a field study of 21 water bodies, the concentrations of endotoxins were much higher in water dominated by cyanobacteria, compared to water with dominance of eukaryotic algae. This observation may partially be explained by the fact that cyanobacteria possess endotoxins and partially by our findings that endotoxin-possessing bacteria inhabit the mucilage of several mass developing cyanobacterial taxa.     

Property Rights in Fisheries: Iceland’s Experience with ITQs

The fundamental problem of economic inefficiency in fisheries, the so-called common property problem, may be seen to be caused by inadequate or lacking property rights in the underlying natural resources. The introduction of Individual Transferable Quotas (ITQs) into fisheries represents an attempt to correct this failure. ITQs, however, are not property rights in the relevant natural resources, i.e. the fish stocks and their habitat. They are merely harvesting rights and thus far from ideal as property rights. Nevertheless, ITQs have been introduced in numerous fisheries around the world, apparently with generally, even consistently, good economic results. This paper outlines the basic theory of property rights and the strengths and weaknesses of ITQs as property rights in fisheries. The paper goes on to discuss the Icelandic ITQ system and compares its property rights value with that of the New Zealand ITQ system and the Norwegian IQ system. Finally, the paper reviews some measures of the economic outcomes of the ITQ system in Iceland.     

Detection of TIMP-2-like protein in Atlantic cod (Gadus morhua) muscle using two-dimensional real-time reverse zymography

Matrix metalloproteinases (MMPs) have been proposed to participate in postmortem degradation of fish muscle connective tissues during storage. In the extracellular matrix (ECM) of mammals, a group of specific tissue inhibitors of metalloproteinases (TIMPs) contributes in regulating the MMPs present. However, little information exists on the presence of TIMPs in fish. In this paper, the presence of TIMPs in the muscle of Atlantic cod (Gadus morhua) was investigated using gelatin affinity chromatography, real-time reverse zymography (RTRZ) and mass spectrometry (MS). Using RTRZ inhibitory action against cod muscle, proteinases binding to gelatin were detected in the muscle. The inhibitor had similar molecular weight (21 kDa) as a human recombinant TIMP-2 used as a reference sample. Because isoforms of TIMP-2 homologues with similar molecular weight have been suggested in fish, a two-dimensional RTRZ (2D RTRZ) method was designed. The new method showed the existence of only one form with inhibitory action against cod muscle proteinases. Finally, de novo sequencing of two peptides derived from the cod muscle inhibitor showed high homology to TIMP-2s both from human and other teleosts.     

Purification and characterization of Atlantic salmon (Salmo salar) fibrinogen

This study describes a purification protocol of salmon fibrinogen that gives a consumable and highly clottable fibrinogen. Some characteristics of salmon and human fibrinogen are compared. Fibrinogen was purified from barium sulphate adsorbed plasma of Atlantic salmon, using two steps of 25% ammonium sulphate precipitation followed by ultrafiltration. The clottability of the purified salmon fibrinogen was 91%. The Aalpha chains of salmon fibrinogen were heterogeneous with a molecular mass of 90-110 kDa, compared to approximately 67 kDa of human fibrinogen Aalpha chains. The Bbeta and gamma chains of salmon and human fibrinogen had molecular masses of approximately 55 and 50 kDa, respectively. Western blotting revealed that polyclonal rabbit anti-human fibrinogen antibodies had affinity for the gamma chains of salmon fibrinogen, making it possible to study factor XIII activity in purified salmon fibrinogen. Cross-linking of either gamma-gamma or gamma-alpha chains was not detected upon incubation of the purified fibrinogen with thrombin and calcium alone, but was detected when clotting was performed in plasma indicating absence of factor XIII activity in the purified product.     

Effect of Facilitation of Local Stakeholder Groups on Equity in Neonatal Survival; Results from the NeoKIP Trial in Northern Vietnam

Background

To operationalize the post-MDG agenda, there is a need to evaluate the effects of health interventions on equity. The aim of this study is to evaluate the effect on equity in neonatal survival of the NeoKIP trial (ISRCTN44599712), a population-based, cluster-randomized intervention trial with facilitated local stakeholder groups for improved neonatal survival in Quang Ninh province in northern Vietnam.

Methods

Semi-structured interviews were conducted with all mothers experiencing neonatal mortality and a random sample of 6% of all mothers with a live birth in the study area during the study period (July 2008-June 2011). Multilevel regression analyses were performed, stratifying mothers according to household wealth, maternal education and mother’s ethnicity in order to assess impact on equity in neonatal survival.

Findings

In the last year of study the risk of neonatal death was reduced by 69% among poor mothers in the intervention area as compared to poor mothers in the control area (OR 0.31, 95% CI 0.15–0.66). This pattern was not evident among mothers from non-poor households. Mothers with higher education had a 50% lower risk of neonatal mortality if living in the intervention area during the same time period (OR 0.50, 95% CI 0.28–0.90), whereas no significant effect was detected among mothers with low education.

Interpretation

The NeoKIP intervention promoted equity in neonatal survival based on wealth but increased inequity based on maternal education.     

The role of parental motivation in family-based treatment for childhood obesity

This study investigated the role of parental motivation (importance, confidence and readiness) for predicting dropout and outcome from family-based behavioral treatment for childhood obesity. Parent and child demographics, adherence to treatment, and weight loss parameters were also explored as potential predictors. Eighty-four obese children (BMI-standard deviation scores (SDS) >2.14) and a participating parent with each child started treatment consisting of 12 weeks of group and individual treatment sessions (24 sessions total) delivered over a period of 18 weeks. Sixty-one families (73%) completed treatment and attended follow-up at 1 year after treatment. Child session attendance and completion of self-monitoring records served as measures of adherence. In regression analyses, parent reports (pretreatment) of confidence for doing well in treatment was the strongest predictor of treatment completion (P = 0.003) as well as early treatment response (weight loss at week 5) (P = 0.003). This variable remained a significant predictor of child weight loss at post-treatment (P = 0.014), but was not associated with child outcome at 1-year follow-up (P > 0.05). The only significant predictor of child weight loss at that point was child baseline weight (P = 0.001). However, pretreatment parent ratings of importance of and readiness for treatment did not predict dropout or weight loss at any point. The results underscore the importance of addressing parental motivation, specifically parental confidence for changing lifestyle related behaviors, early in the treatment process. Doing so may reduce treatment dropout and enhance treatment outcome.