Sickness Absence from Work among Persons with New Physician-Diagnosed Carpal Tunnel Syndrome: A Population-Based Matched-Cohort Study

Background

Carpal tunnel syndrome is common among employed persons. Data on sickness absence from work in relation to carpal tunnel syndrome have been usually based on self-report and derived from clinical or occupational populations. We aimed to determine sickness absence among persons with physician-diagnosed carpal tunnel syndrome as compared to the general population.

Methods

In Skåne region in Sweden we identified all subjects, aged 17–57 years, with new physician-made diagnosis of carpal tunnel syndrome during 5 years (2004–2008). For each subject we randomly sampled, from the general population, 4 matched reference subjects without carpal tunnel syndrome; the two cohorts comprised 5456 and 21,667 subjects, respectively (73% women; mean age 43 years). We retrieved social insurance register data on all sickness absence periods longer than 2 weeks from 12 months before to 24 months after diagnosis. Of those with carpal tunnel syndrome 2111 women (53%) and 710 men (48%) underwent surgery within 24 months of diagnosis. We compared all-cause sickness absence and analyzed sickness absence in conjunction with diagnosis and surgery.

Results

Mean number of all-cause sickness absence days per each 30-day period from 12 months before to 24 months after diagnosis was significantly higher in the carpal tunnel syndrome than in the reference cohort. A new sickness absence period longer than 2 weeks in conjunction with diagnosis was recorded in 12% of the women (n = 492) and 11% of the men (n = 170) and with surgery in 53% (n = 1121) and 58% (n = 408) of the surgically treated, respectively; median duration in conjunction with surgery was 35 days (IQR 27–45) for women and 41 days (IQR 28–50) for men.

Conclusions

Persons with physician-diagnosed carpal tunnel syndrome have substantially more sickness absence from work than age and sex-matched persons from the general population from1 year before to 2 years after diagnosis. Gender differences were small.     

Failed protective effort of ex situ conservation of River Vistula trout (Salmo trutta) in Sweden

Environmental Biology of Fishes - Ex situ conservation comprises some of the oldest and best-known conservation methods and it has been applied for different fish stocks. This study describes...     

Neuronal dynamics underlying high- and low-frequency EEG oscillations contribute independently to the human BOLD signal

Work on animals indicates that BOLD is preferentially sensitive to local field potentials, and that it correlates most strongly with gamma band neuronal synchronization. Here we investigate how the BOLD signal in humans performing a cognitive task is related to neuronal synchronization across different frequency bands. We simultaneously recorded EEG and BOLD while subjects engaged in a visual attention task known to induce sustained changes in neuronal synchronization across a wide range of frequencies. Trial-by-trial BOLD fluctuations correlated positively with trial-by-trial fluctuations in high-EEG gamma power (60-80 Hz) and negatively with alpha and beta power. Gamma power on the one hand, and alpha and beta power on the other hand, independently contributed to explaining BOLD variance. These results indicate that the BOLD-gamma coupling observed in animals can be extrapolated to humans performing a task and that neuronal dynamics underlying high- and low-frequency synchronization contribute independently to the BOLD signal.     

Multilocus genotyping of human Giardia isolates suggests limited zoonotic transmission and association between assemblage B and flatulence in children

Background

Giardia intestinalis is one of the most common diarrhea-related parasites in humans, where infection ranges from asymptomatic to acute or chronic disease. G. intestinalis consists of eight genetically distinct genotypes or assemblages, designated A–H, and assemblages A and B can infect humans. Giardiasis has been classified as a possible zoonotic disease but the role of animals in human disease transmission still needs to be proven. We tried to link different assemblages and sub-assemblages of G. intestinalis isolates from Swedish human patients to clinical symptoms and zoonotic transmission.

Methodology/Principal Findings

Multilocus sequence-based genotyping of 207 human Giardia isolates using three gene loci: ß-giardin, glutamate dehydrogenase (gdh), and triose phosphate isomerase (tpi) was combined with assemblage-specific tpi PCRs. This analysis identified 73 patients infected with assemblage A, 128 with assemblage B, and six with mixed assemblages A+B. Multilocus genotypes (MLGs) were easily determined for the assemblage A isolates, and most patients with this genotype had apparently been infected through anthroponotic transmission. However, we also found evidence of limited zoonotic transmission of Giardia in Sweden, since a few domestic human infections involved the same assemblage A MLGs previously reported in Swedish cats and ruminants. Assemblage B was detected more frequently than assemblage A and it was also more common in patients with suspected treatment failure. However, a large genetic variability made determination of assemblage B MLGs problematic. Correlation between symptoms and assemblages was found only for flatulence, which was significantly more common in children less than six years of age infected with assemblage B.

Conclusions/Significance

This study shows that certain assemblage A subtypes are potentially zoonotic and that flatulence is connected to assemblage B infections in young children. Determination of MLGs from assemblages A and B can be a valuable tool in outbreak situations and to help identify possible zoonotic transmission.     

The effects of arg-vasopressin on osteoblast-like cells in endothelial nitric oxide synthase-knockout mice and their wild type counterparts

In the present study, we investigated whether nitric oxide (NO) could be involved in the effects of arg-vasopressin (AVP) on osteoblast-like cells. Cells derived from endothelial nitric oxide synthase (eNOS)-knockout mice and their wild type (WT) counterparts, and an osteosarcoma cell line (SaOS-2) were used. AVP (10-100 pmol/l) increased proliferation of osteoblast-like cells from WT mice. The effect was abolished by an AVP V1-receptor antagonist. AVP increased proliferation of cells from eNOSKO mice only when a NO donor, SNAP, was added. A nitric oxide synthase-inhibitor, L-NAME, antagonized the increase in cell proliferation in response to AVP in SaOS-2 cells. In conclusion, this study indicates that NO is involved in the effects of AVP on cell proliferation in osteoblast-like cells.     

Characterization of phase separation in film forming biopolymer mixtures

Enhanced, tailor-made films can be achieved by combining the good gas barrier of the hydrophilic high amylose maize starch (hylon) with the water resistance of the hydrophobic protein zein. Two polymers are not always miscible in solution, and the phase separation behavior of the mixture is therefore important for the final film structure and its properties. Phase separation of a mixture of these two biopolymers was induced either by cooling, which was observed as growing droplets of the hylon phase which in some cases also formed small aggregates, or by solvent evaporation and studied in real-time in a confocal laser scanning microscope. Solvent evaporation had a much stronger effect on phase separation. During the early stage of phase separation, hylon formed large aggregates and subsequently smaller droplets coalesced with other droplets or large hylon aggregates. The later part of the separation seemed to take place through spinodal decomposition.     

Effects of acute hyperosmolality on blood-brain barrier function in ovine fetuses and lambs

We examined the effects of hyperosmolality on blood-brain barrier (BBB) permeability during development to test the vulnerability of the immature barrier to stress. The BBB response to hyperosmolality was quantified using the blood-to-brain transfer constant (Ki) with alpha-aminoisobutyric acid in fetuses at 60% and 90% gestation, premature, newborn, and older lambs. Ki plotted against osmolality increased as a function of increases in osmolality in all groups and brain regions. The relationship was described (P < 0.05) by a segmented regression model. At lower osmolalities, changes in Ki were minimal, but after a break point (threshold) was reached, the increase (P < 0.05) was linear. We examined the responses of Ki to hyperosmolality within each brain region by comparing the thresholds and slopes of the second regression segment. Lower thresholds and higher slopes imply greater vulnerability to hyperosmolality in the younger groups. Thresholds increased (P < 0.05) with development in the thalamus, superior colliculus, pons, and spinal cord, and slopes of the second regression segment decreased (P < 0.05) in the cerebellum, hippocampus, inferior colliculus, medulla, and spinal cord. BBB resistance to hyperosmolality increased (P < 0.05) with development in most brain regions. The pattern of the Ki plotted against osmolality was (P < 0.05) heterogenous among brain regions in fetuses and premature and newborn lambs, but not in older lambs. We conclude that 1) BBB permeability increased as a function of changes in osmolality, 2) the barrier becomes more resistant to hyperosmolality during development, and 3) the permeability response to hyperosmolality is heterogenous among brain regions in fetuses and premature and newborn lambs.     

Crystal structure of a SEA variant in complex with MHC class II reveals the ability of SEA to crosslink MHC molecules

Although the biological properties of staphylococcal enterotoxin A (SEA) have been well characterized, structural insights into the interaction between SEA and major histocompatibilty complex (MHC) class II have only been obtained by modeling. Here, the crystal structure of the D227A variant of SEA in complex with human MHC class II has been determined by X-ray crystallography. SEA(D227A) exclusively binds with its N-terminal domain to the alpha chain of HLA-DR1. The ability of one SEA molecule to crosslink two MHC molecules was modeled. It shows that this SEA molecule cannot interact with the T cell receptor (TCR) while a second SEA molecule interacts with MHC. Because of its relatively low toxicity, the D227A variant of SEA is used in tumor therapy.     

Spatial and Temporal Analysis of Contact Rates in Female White-Tailed Deer

Abstract: White-tailed deer (Odocoileus virginianus) are important game mammals and potential reservoirs of diseases of domestic livestock; thus, diseases of deer are of great concern to wildlife managers. Contact, either direct or indirect, is necessary for disease transmission, but we know little about the ecological contexts that promote intrasexual contact among deer. Using pair-wise direct contacts estimated from Global Positioning System collar locations and joint utilization distributions (JUDs), we assessed habitats in which contacts occur to test whether direct contact rates among female white-tailed deer in different social groups differs among land-cover types. We also tested whether contact rates differed among seasons, lunar phases, and times of day. We obtained locations from 27 female deer for periods of 0.5–17 months during 2002–2006. We designated any simultaneous pair of locations for 2 deer <25 m apart as a direct contact. For each season, we used compositional analysis to compare land-cover types where 2 deer had contact to available land-cover weighted by their JUD. We used mixed-model logistic regression to test for effects of season, lunar phase, and time of day on contact rates. Contact rates during the gestation season were greater than expected from random use in forest and grassland cover, whereas contact rates during the fawning period were greater in agricultural fields than in other land-cover types. Contact rates were greatest during the rut and lowest in summer. Diel patterns of contact rates varied with season, and contact rates were elevated during full moon compared to other lunar periods. Both spatial and temporal analyses suggest that contact between female deer in different social groups occurs mainly during feeding, which highlights the potential impact of food distribution and habitat on contact rates among deer. By using methods to associate contacts and land-cover, we have created beneficial tools for more elaborate and detailed studies of disease transmission. Our methods can offer information necessary to develop spatially realistic models of disease transmission in deer.