Cost of In-Patient Care over 7 Years among Surgically and Conventionally Treated Obese Patients

Objective: Bariatric surgery improves cardiovascular risk factors and quality of life, but few studies have directly addressed the relation between obesity treatment and hospitalization costs. This prospective controlled study compares in-patient care between surgically and conventionally treated obese patients. Research Methods and Procedures: A total of 962 surgically and conventionally treated obese patients from the intervention study, Swedish Obese Subjects, were followed for 6 years. Changes in days of hospitalization and hospitalization costs were analyzed. Information on hospitalizations for each subject were obtained from the Swedish Hospital Discharge Register. Results: After 6 years, weight change was −16.7% in the surgical group and +0.9% in the control group (p < 0.0001). The cumulated hospital stay over 6 years was 23.4 days in the surgical group and 6.9 days in the control group (p < 0.0001). The average hospital cost for the surgical intervention was US$4300. Incremental costs that could be attributable to obesity surgery averaged US$1200 per year. After exclusion of hospitalizations for the surgical intervention and conditions common after bariatric surgery, there were no significant differences between the groups in number of hospital days or hospitalization costs. Discussion: Our experience from bariatric surgery indicates that average weight reductions of 16% will not reduce hospitalization costs over 6 years. Costs of bariatric surgery are limited and seem to be motivated given the marked improvements of cardiovascular risk factors, cardiac structure, and function and health-related quality of life.     

Brown trout Salmo trutta released to support recreational fishing in a Norwegian fjord

One- and two-year-old hatchery reared juveniles of seven freshwater resident and anadromous populations of Scandinavian brown trout were released in the outer and inner part of the Oslofjord and in the River Akerselva, flowing through the city of Oslo. Recapture rates were highest (mean 20.3%) for river released fish and lowest for those released in the outer (16.8%) and inner (12.1%) fjord. In general, recapture rate increased with fish size at release (r=0.76). When released in fresh water, most of the recaptures were from fresh water and when released in the fjord, most recaptures were from the fjord. In general, freshwater resident stocks showed a higher degree of freshwater residency than anadromous stocks. However, mean migratory distance was longer for freshwater resident than anadromous fish. Trout moved longer distances at sea when released in the outer than in the inner fjord. Specific growth rate and size at recapture varied among release sites and stocks; they were highest for fish released in the outer fjord and lowest for river-released trout. There was no consistent difference in sea growth between freshwater resident and anadromous stocks. Estimated total yield was highest for fish released in the outer fjord, whereas there was no significant difference in yields between trout released in the river and the inner Oslofjord.     

The influence of exogenous PMS and HCG on the arachidonic acid content of the immature rat ovary.

The influence of exogenous PMS and/or HCG, on the arachidonic acid (C 20:4omega6) content of the immature rat ovary was examined. Changes in ovarian arachidonate content associated with hormone administration were assessed in total lipid extracts, and in several neutral and phospholipid fractions. Both relative percentage and absolute amounts of arachidonic acid in several lipids were measured as well as uptake of radioactivity into total lipid resulting from the administration of 3H-labeled arachidonic acid in vivo. On the basis of these studies, we conclude (1) PMS, with or without HCG promotes increased uptake of exogenous arachidonic acid into ovarian total lipids; (2) Arachidonic acid is a mojor fatty acid constituent from noncholine containing phosphatides at the onset of normal estrous (ca. 38 days) even in the animals which received no PMS or HCG; (3) Changes in ovarian arachidonic acid levels following gonadotropin administration are more striking in the two phospholipid fractions than in the two neutral lips examined; (4) PMS is associated with a rapid outpouring of ovarian lipid, accompanied by a high turnover of arachidonic acid which is enhanced or modified temporally by added HCG in vivo. These results provide the first quantitative evidence that gonadotropins may regulate prostaglandin biosynthesis in the ovary by their effects on the uptake, storage, or release of arachidonic acid, a major PG precursor, from specific ovarian lipids. While the data strongly suggest that the regulation of one or more ovarian esterases (cholesterol esterase, lipase, phospholipase) is the mechanism by which gonadotropins regulate PG biosynthesis, a direct action on PG synthetase is not ruled out.     

Production of diaspores at the landscape level regulates local colonization: an experiment with a spore‐dispersed moss

Effective dispersal is crucial to species inhabiting transient substrates in order for them to be able to persist in a landscape. Bryophytes, pteridophytes, lichens and fungi all have wind‐dispersed small diaspores and can be efficiently dispersed if their diaspores reach air masses above canopy height. However, empirical data on dispersal over landscape scales are scarce. We investigated how the colonization of an acrocarpous clay‐inhabiting pioneer moss, Discelium nudum, varied between sites that differed in connectivity to potential dispersal sources at spatial scales from 1 to 20 km in a region in northern Sweden. We recorded the colonization on ?25 introduced clay heaps at each of 14 experimental sites some months after the dispersal period. The colonization rate ranged from 0–82% and had a statistically significant relationship with a proxy for potential habitats (amount of clay‐dominated soil) in a buffer of 20 km radius surrounding the experimental sites (and also weakly with the amount of substrate in a 10 km buffer). There were no significant relationships between colonization rate and connectivity at smaller scales (1 and 5 km). We made a rough estimate of the number of spores available for dispersal in a landscape, given the amount of clay‐dominated soil, by recording the number of Discelium nudum colonies in two 25 × 25 km landscapes. The estimated available spore numbers in the different 20 km buffers were of the same order of magnitude as the deposition densities at the experimental sites calculated from the colonization rates. The results suggest that the spores of species with scattered occurrences and small diaspores (25 μm) in open landscapes can be deposited over extensive areas, at rates high enough to drive colonization patterns. This also implies that regional connectivity may be more important than local connectivity for these kinds of species.     

Trophic interactions affect the population dynamics and risk of extinction of basal species in food webs

This paper addresses effects of trophic complexity on basal species, in a Lotka–Volterra model with stochasticity. We use simple food web modules, with three trophic levels, and expose every species to random environmental stochasticity and analyze (1) the effect of the position of strong trophic interactions on temporal fluctuations in basal species’ abundances and (2) the relationship between fluctuation patterns and extinction risk. First, the numerical simulations showed that basal species do not simply track the environment, i.e. species dynamics do not simply mirror the characteristics of the applied environmental stochasticity. Second, the extinction risk of species was related to the fluctuation patterns of the species.More specifically, we show (i) that despite being forced by random stochasticity without temporal autocorrelation (i.e. white noise), there is significant temporal autocorrelation in the time series of all basal species’ abundances (i.e. the spectra of basal species are red-shifted), (ii) the degree of temporal autocorrelation in basal species time series is affected by food web structure and (iii) the degree of temporal autocorrelation tend to be correlated to the extinction risks of basal species.Our results emphasize the role of food web structure and species interactions in modifying the response of species to environmental variability. To shed some light on the mechanisms we compare the observed pattern in abundances of basal species with analytically predicted patterns and show that the change in the predicted pattern due to the addition of strong trophic interactions is correlated to the extinction risk of the basal species. We conclude that much remain to be understood about the mechanisms behind the interaction among environmental variability, species interactions, population dynamics and vulnerability before we quantitatively can predict, for example, effects of climate change on species and ecological communities. Here, however, we point out a new possible approach for identifying species that are vulnerable to environmental stochasticity by checking the degree of temporal autocorrelation in the time series of species. Increased autocorrelation in population fluctuations can be an indication of increased extinction risk.     

Anti-HMGB1 auto-Abs influence fatigue in patients with Crohn’s disease

Fatigue is common in all chronic inflammatory and autoimmune diseases. A conceptual model for understanding the biological basis of fatigue describes it as being a part of the sickness behaviour response generated by pro-inflammatory cytokines and other mediators. We hypothesised that the pro-inflammatory high mobility group box 1 (HMGB1) protein is a fatigue-inducing molecule and that auto-Abs against HMGB1 reduce fatigue. We measured Abs against disulphide (ds) HMGB1 and fully reduced (fr) HMGB1 in plasma from 57 patients with Crohn’s disease. Fatigue was rated using the fatigue visual analogue scale (fVAS) and disease activity with faecal calprotectin, C-reactive protein and the Simple Endoscopic Score for Crohn’s disease. Multivariable regression models identified anti-dsHMGB1 and anti-frHMGB1 Abs as the strongest contributing factors for fVAS scores (B = −29.10 (P = 0.01), R² = 0.17, and B = −17.77 (P = 0.01), R² = 0.17, respectively). Results indicate that anti-HMGB1 auto-Abs alleviate fatigue possibly by down-regulating HMGB1-induced sickness behaviour.     

Comparative Genetic Structure of the Threatened Tenebrionid Beetle Oplocephala haemorrhoidalis and its Common Relative Bolitophagus reticulatus

We used RAPD and allozyme genetic markers to compare the genetic structures of a threatened saproxylic tenebrionid beetle, Oplocephala haemorrhoidalis, and its common relative (different subfamilies), Bolitophagus reticulatus, to evaluate the relative importance of habitat fragmentation on the occurrence of the two species. O. haemorrhoidalis showed significantly higher levels of genetic differentiation between sites than B. reticulatus for both types of genetic marker. Patterns of isolation by distance were consistent with (B. reticulatus) or close to (O. haemorrhoidalis) theoretical expectations for equilibrium between gene flow and genetic drift. For O. haemorrhoidalis, the RAPD-patterns also showed a steeper increase in isolation by distance where geographic distances were small than at larger distances. This suggests that gene flow between the populations of O. haemorrhoidalis has declined as an effect of recent habitat fragmentation and is probably relatively restricted at present. For B. reticulatus, levels of genetic differentiation were low, suggesting that B. reticulatus readily moves over large areas. Genetic variability was not low in either species. Genetic differentiation among and relatedness within fruiting bodies varied substantially within sites for both species. This variation was probably due to founder events: when levels of relatedness were close to zero, genetic differentiation was also low.     

Influences of river regulation and environmental variables on upland bird assemblages in northern Sweden

Most large rivers in Sweden are regulated to produce hydropower. This transformation from free-flowing rivers to chains of elongate run-of-river impoundments has been shown to have consequences for aquatic, riparian and adjacent upland environments, and for the emergence patterns of aquatic insects that are important for terrestrial consumers. In this study, we investigated bird assemblages in upland-forest environments along seven large rivers (three heavily impounded and four free flowing) in northern Sweden. Bird densities were assessed by point counts in the breeding and post-breeding seasons. While we observed no significant differences in bird species richness between regulated and free-flowing rivers, cumulative densities of two feeding groups of birds (those feeding on seeds and/or large insects and those feeding on small insects) were higher along free-flowing rivers than along regulated rivers in the breeding season, consistent with known differences in aquatic-insect emergence. Further, ordination analyses showed seasonal shifts in bird assemblage structure, and that these shifts differed between regulated and free-flowing rivers and between the two feeding groups. However, the variables explaining the most variance (11?C28?%) in bird assemblage structure were related to a gradient of agricultural-to-forest land use. River regulation contributed to the model in the post-breeding season, but was of relatively low importance. Nevertheless, the observed contrasting seasonal shifts in upland-forest bird assemblage structure between regulated and free-flowing rivers suggest that regulation-induced modifications of aquatic-insect emergence and subsequent changes in prey availability to the birds are also important considerations.