The influence of season, hunting mode, and habitat specialization on riparian spiders as key predators in the aquatic-terrestrial linkage

Freshwater ecosystems subsidize riparian zones with high-quality nutrients via the emergence of aquatic insects. Spiders are dominant consumers of these insect subsidies. However, little is known about the variation of aquatic insect consumption across spiders of different hunting modes, habitat specializations, seasons, and systems. To explore this, we assembled a large stable isotope dataset (n > 1000) of aquatic versus terrestrial sources and six spider species over four points in time adjacent to a lotic and a lentic system. The spiders represent three hunting modes each consisting of a wetland specialist and a habitat generalist. We expected that specialists would feed more on aquatic prey than their generalist counterparts. Mixing models showed that spiders' diet consisted of 17-99% of aquatic sources, with no clear effect of habitat specialization. Averaged over the whole study period, web builders (WB) showed the highest proportions (78%) followed by ground hunters (GH, 42%) and vegetation hunters (VH, 31%). Consumption of aquatic prey was highest in June and August, which is most pronounced in GH and WBs, with the latter feeding almost entirely on aquatic sources during this period. Additionally, the elevated importance of high-quality lipids from aquatic origin during fall is indicated by elemental analyses pointing to an accumulation of lipids in October, which represent critical energy reserves during winter. Consequently, this study underlines the importance of aquatic prey irrespective of the habitat specialization of spiders. Furthermore, it suggests that energy flows vary substantially between spider hunting modes and seasons.

[Exposure of Pupils to Recreational Noise from Portable Listening Devices and Possible Preventive Measures]

Background and Objectives: Exposure to recreational noise is becoming increasingly important due to a change in leisure behavior amongst children and adolescents. The aim of this pilot study was to assess exposure of 6^th grade pupils to recreational noise from portable listening devices (PLD). Furthermore, preventive measures to reduce recreational noise exposure should be identified. Methods: In "Ohrkan Kids", 38 Bavarian pupils aged 11 to 14 were interviewed regarding their music listening behavior using a standardized questionnaire. In addition, measurements of commonly used volume settings on the children's portable listening devices were carried out. Furthermore, the German Social Accident Insurance (DGUV), health insurance companies as well as health and education ministries of the German federal states were surveyed regarding their activities in the prevention of recreational noise exposure. Results: Based on the questionnaire data for weekly usage, 10 out of 31 children (32.3%) exceeded the upper exposure value of 85 dB recommended by labor protection law. Taking actually measured values, 9 out of 31 children (29%) exceeded this level. The DGUV and some federal states carry out specific projects for the prevention of recreational noise exposure. Conclusion: The large number of children with hazardous music consumption indicates that measures for the prevention of noise-induced hearing loss are already required for 11 to 14 year olds. To maximize the number of children addressed, age-appropriate and target-group-specific preventive measures are needed. As there are only few studies which examined the effectiveness of awareness campaigns for the prevention of recreational noise, any future prevention projects should be evaluated with an increased focus on estimating their effectiveness.

[Taking Care of Asylum Seekers: Occupational Health Aspects with a Special Focus on Vaccination]

Employees and volunteers often feel insecure about the potential transmission of infectious diseases when taking care of asylum seekers. It could be shown that overall only a minor risk of infection emanates from asylum seekers. However, aspects of occupational health and vaccination should be kept in mind.Besides the standard vaccination the Standing Committee on Vaccination (STIKO) recommends for occupational indication, which is given for employees and volunteers in asylum facilities, vaccination against hepatitis A, hepatitis B, polio (if the last vaccination was more than 10 years before) as well as influenza (seasonal).According to the German Occupational Safety and Health Act taking care of the employer has to determine which exposures might occur at the workplace (risk assessment) and define necessary protection measures. Depending on task and exposure when taking care of asylum seekers different acts (e. g. biological agents regulation) and technical guidelines for the handling biological agents (e. g. TRBA 250 or TRBA 500) have to be applied.The Bavarian Health and Food Safety Authority (LGL) has published several information sheets regarding "asylum seekers and health management" for employees and volunteers from the non-medical as well as the medical area (www.lgl.bayern.de search term "Asylbewerber"). With theses publications insecurities in taking care of asylum seekers should be prevented. Furthermore the employer gets support in the implementation of legal obligations to ensure occupational safety for the employees.

First detection of Borrelia burgdorferi-antibodies in free-living birds of prey from Eastern Westphalia, Germany

Borrelia (B.) burgdorferi sensu lato, the causative agent of Lyme disease, is the most important arthropod-borne zoonosis-pathogen in the Northern hemisphere. Besides small mammals, birds, primarily Passeriformes and sea birds, play an important role in the transmission, distribution and maintenance of this disease. Previous studies on birds have focused mainly on the detection of Borrelia-infected ticks. However, the presence or absence of an infected tick cannot be taken as an indicator of the infective status of the avian host; to date this area of research has not been explored. In this study, serological analyses of blood collected from free-living birds of prey (n = 29) at the rehabilitation centre in Eastern Westphalia, Germany, highlights that birds of prey are also susceptible to B. burgdorferi and react immunologically to an infection. Increased antibody-levels could be found by using a modified Indirect Immunofluorescent-testing in two common buzzards, Buteo buteo, and two eagle owls, Bubo bubo. Further research regarding the serological diagnostics of B. burgdorferi within the avian host is required. In the future, it should be taken into account that birds of prey can be reservoirs for B. burgdorferi, as well as carriers of infected ticks; although at present their epidemiological importance is still to be confirmed.

Trends in the incidence of visual impairment certification secondary to diabetic retinopathy in the Leeds metropolitan area, 2005-2010

AIM

This study reports the incidence of visual impairment certification due to diabetic retinopathy in Leeds between 2008 and 2010 and makes a comparison with data from 2005, immediately before the introduction of a comprehensive screening service.

METHODS

The primary causes of visual impairment certification between 2008 and 2010 were collected and reviewed. Mid-year population estimates and a diabetes prevalence model were used to determine the incidence of certification secondary to diabetic retinopathy.

RESULTS

Diabetic retinopathy was the primary cause of visual impairment certification in 33 of 446 (7.4%) certificates in 2008, 34 of 410 (8.3%) certificates in 2009 and 24 of 392 (6.1%) in 2010. For the total population in 2008, 2009 and 2010, the combined incidence of either sight impairment or severe sight impairment due to diabetic retinopathy was 42.3, 43.2 and 30 per million per year, respectively. For the population with diagnosed diabetes mellitus, the combined incidence of either sight impairment or severe sight impairment secondary to diabetic retinopathy was 1227, 1192 and 796 per million per year, respectively. For each year, the incidence of visual impairment was lower than the corresponding figure for 2005.

CONCLUSION

Following the introduction of a comprehensive retinal screening service, the incidence of visual impairment certification secondary to diabetic retinopathy in the Leeds Metropolitan area appears to be decreasing. However, a multifaceted approach, addressing all the avoidable risk factors, may be required to maintain this trend in view of the increasing prevalence of Type 2 diabetes.

The predictive value of OCT characteristics for the visual outcome in neovascular AMD

BACKGROUND

The intravitreal injection of an anti-VEGF compound is the current standard of care in neovascular AMD. The response to this therapy varies greatly. To date it was not possible to determine clear predictive factors in regard to therapy response, thus making it difficult when counselling patients regarding the probability for visual improvement. The aim of this study was to evaluate baseline OCT characteristics in regard to their predictive value on the outcome of visual acuity (VA) after 12 months.

PATIENTS AND METHODS

A retrospective analysis of 75 eyes with neovascular AMD treated with intravitreal anti-VEGF injections at the University Hospital of Zurich with a documented follow-up of at least 12 months. Measurement and comparison of the following OCT structures were undertaken: central retinal thickness (CRT), integrity of the IS/OS junction, and presence of intra- or subretinal fluid. VA at baseline and after 12 months was evaluated. OCT findings were compared between eyes that gained ≥ 5 letters ETDRS (group 1) and eyes that did not (group 2).

RESULTS

75 eyes with a mean baseline VA of 57.2 ± 15 letters and a mean baseline CRT of 430 ± 226 μm were analyzed. Although baseline VA did not differ statistically significantly, eyes in group 2 had a higher VA than eyes in group 1 (60.2 ± 16.2 vs. 54.9 ± 13.6, p = 0.123). In group 1 the change of VA after 12 months was 12.6 ± 8.0 letters while it was -5.0 ± 7.8 letters in group 2. No statistically significant differences between the two groups with respect to the analyzed OCT parameters were found. None of the analyzed OCT factors had a predictive value regarding the VA outcome at month 12.

CONCLUSIONS

Our study was not able to find baseline OCT parameters that could predict the course of VA after 12 months. However, eyes with a thicker central retinal thickness at presentation showed a greater reduction in CRT during the analyzed period. This was associated with a more favourable course in VA. Perhaps this might be due to a less pronounced initial morphological retinal damage.

The phosphatidylserine receptor mediates phagocytosis by vascular smooth muscle cells

Apoptosis participates in every step of atherogenesis, but the process of clearance of apoptotic cells by phagocytosis has been underestimated. Rapid removal of apoptotic cells is critical for tissue homeostasis, in order to avoid accumulation of necrotic material and subsequent inflammation in the pathological vascular wall. We have demonstrated by RT-PCR, western blot and immunocytofluorescence that vascular smooth muscle cells (VSMCs) express the phosphatidylserine receptor (PSR). We then tested the involvement of PSR in the ability of VSMCs to bind and engulf apoptotic cells. We used a model of senescent erythrocytes, which expose PS after 4 days of culture (85% of cells relative to 8% in freshly isolated erythrocytes). The pseudo-peroxidase activity of haemoglobin contained within erythrocytes allowed us to quantify per se both binding and phagocytosis by VSMCs. We have also shown by light and confocal microscopy that VSMCs were able to ingest aged erythrocytes. Addition of a blocking antibody or transfection of VSMCs by a siRNA directed against PSR reduced the binding and engulfment of aged erythrocytes by more than 90%. These results suggest that PSR is involved in phagocytosis of PS-presenting cells. Incubation of aged erythrocytes with VSMCs also significantly increased the expression of PSR, suggesting that the tethering/ingestion of apoptotic cells triggers this process. Immunostaining for PSR in complicated atherosclerotic plaques shows positivity in the media and macrophage-rich areas. The mechanisms underlying phagocytosis and involving PSR in vivo, within the pathological arterial wall, deserve further investigation.

HMGA1 controls transcription of insulin receptor to regulate cyclin D1 translation in pancreatic cancer cells

The HMGA1 proteins act as architectural transcription factors and are involved in the regulation of genes important in the process of carcinogenesis. Although HMGA1 proteins are overexpressed in most types of cancer, signaling circuits regulated by HMGA1 are not clarified in detail. In this study, we show that HMGA1 proteins promote proliferation of pancreatic cancer cells by accelerating G(1) phase progression. Transfection of HMGA1-specific small interfering RNA (siRNA) activates the RB-dependent G(1)-phase checkpoint due to the impaired expression of cyclin D1. Down-regulation of cyclin D1 after the HMGA1 knockdown is due to translational control and involves the repressor of the eukaryotic translation initiation factor 4E (eIF4E) 4E-BP1. We show that 4E-BP1 and cyclin D1 act downstream of the insulin receptor (IR) in pancreatic cancer cells. At the molecular level transcription of the IR is controlled by a CAAT/enhancer binding protein beta (C/EBPbeta)/HMGA1 complex. Together, this work defines a novel pathway regulated by HMGA1, which contributes to the proliferation of pancreatic cancer cells.

European dissemination of a web- and case-based learning system for occupational medicine: NetWoRM Europe

OBJECTIVE

Occupation has a large impact on health in Europe. In order to prevent and recognize occupational diseases, medical students and physicians should know about the potentially causal relationship between profession and diseases as well as the basic legal aspects of occupational medicine (OM). However, the opportunity of bedside teaching, the students' most favoured way of teaching, is limited.

METHODS

One possibility to complete and improve traditional training in OM is computer-oriented case-based learning. Using the authoring system "CASUS" (INSTRUCT AG) cases can be created and handled without knowledge in computer sciences.

RESULTS

So far, 19 cases have been created and evaluated by students of German universities. Due to the great efforts arising from the creation of such multimedia cases it is desirable and cost-effective to use the existing cases at several medical universities. Therefore, the Net-based Training in Work-Related Medicine (NetWoRM) project shares cases on an international base. In February and April 2005, 13 case-authors from 12 centres were trained in the basics of case creation during a 3 week programme in Munich. The overall evaluation of the participants indicated that this way of teaching case creation is very efficient. Up to now, nine cases were translated into English and five into Spanish. First implementation of the cases in Spain and Finland showed a good acceptance by the students but more evaluation has still to be done.

CONCLUSION

Based on these results we conclude that exchange of case-based e-learning in OM is feasible and rewarding on an international base.

Maternal predictors of subcutaneous fat in the term newborn

AIM

To determine the relative influences of some maternal factors on skinfold thickness. The effects of age, parity, height, body mass index (BMI) and pregnancy weight gain (PWG) of the mother on the subscapular skinfold thickness (SST) of the newborn were estimated, and compared with their effects on birthweight (BW), crown-heel length (CHL) and head circumference (HC).

METHODS

A sample of 13, 972 healthy, term singletons was selected at the Clamart Maternity Hospital (France). Stepwise regressions were used to determine the most predictive maternal factors for each parameter in the newborn. The respective effects of the mother's age and parity on each newborn dimension were tested by analysis of variance.

RESULTS

The SST is a singular parameter, influenced by the mother's BMI and PWG, but not by her height. In contrast, the main predictor of BW, CHL and HC is the height of the mother, and to a lesser extent her PWG and BMI. Parity and maternal age have a smaller effect, except on SST, and essentially between the first and second pregnancies.

CONCLUSION

These results clearly separate SST from other newborn dimensions. The skinfold thickness depends only on the nutritional status of the mother, while other dimensions are markedly influenced by the genetic background. This study is the first to demonstrate the singularity of skinfold thickness in newborn infants as a marker of the mother's nutritional status.

A maize-specifically expressed gene cluster in Ustilago maydis

The corn pathogen Ustilago maydis requires its host plant maize for development and completion of its sexual cycle. We have identified the fungal mig2-1 gene as being specifically expressed during this biotrophic stage. Intriguingly, mig2-1 is part of a gene cluster comprising five highly homologous and similarly regulated genes designated mig2-1 to mig2-5. Deletion analysis of the mig2-1 promoter provides evidence for negative and positive regulation. The predicted polypeptides of all five genes lack significant homologies to known genes but have characteristic N-terminal secretion sequences. The secretion signals of mig2-1 and mig2-5 were shown to be functional, and secretion of a full length Mig2-1-eGFP fusion protein to the extracellular space was demonstrated. The central domains of the Mig2 proteins are highly variable whereas the C-termini are strongly conserved and share a characteristic pattern of eight cysteine residues. The mig2 gene cluster was conserved in a wide collection of U. maydis strains. Interestingly, some U. maydis isolates from South America had lost the mig2-4 gene as a result of a homologous recombination event. Furthermore, the related Ustilago scitaminea strain, which is pathogenic on sugar cane, appears to lack the mig2 cluster. We describe a model of how the mig2 cluster might have evolved and discuss its possible role in governing host interaction.

Germline mutations in the p73 gene do not predispose to familial prostate-brain cancer

BACKGROUND

Analysis of high-risk prostate cancer (PC) families with at least one confirmed case of primary brain cancer (BC) has identified a region of genetic linkage on chromosome 1p36 termed CAPB. The p36 region of chromosome one has been reported to have frequent loss of heterozygosity (LOH) in brain and central nervous system (CNS) tumors and epidemiological studies have shown an increased relative risk of BC and tumors of the CNS in PC families. In 1997 a reported tumor suppressor with high homology to p53, termed p73, was mapped to the p36 region of chromosome one. Here, we examine the p73 gene as a potential candidate for CAPB.

METHODS

Ninety-four members from the 12 prostate-brain cancer families in which linkage was originally found were examined. The complete coding region and intron-exon boundaries of the p73 gene were analyzed for germline mutations by Single Stranded Conformational Polymorphism analysis (SSCP) and direct DNA sequencing.

RESULTS

Silent nucleotide substitutions only were detected within the coding regions of the gene in affected individuals. Nucleotide changes were detected in introns 1, 6, 8, 9, and 10, but all were located >or=16 base pairs from the splice site, and are thus unlikely to be deleterious mutations.

CONCLUSIONS

Germline mutations in the p73 gene are unlikely to be critical for inherited susceptibility to PC in this specified subset of families.

Clinical characteristics of prostate cancer in an analysis of linkage to four putative susceptibility loci

PURPOSE

Hereditary prostate cancer is an etiologically heterogeneous disease with six susceptibility loci mapped to date. We aimed to describe a collection of high-risk prostate cancer families and assess linkage to multiple markers at four loci: HPC1 (1q24-25), PCaP (1q42.2-43), HPCX (Xq27-28), and CAPB (1p36).

EXPERIMENTAL DESIGN

Medical record data on 505 affected men in 149 multiply-affected prostate cancer families were reviewed, and correlations of clinical traits within each family were calculated. Logarithm of odds (LOD) score and nonparametric (NPL) linkage analyses were performed; white families were stratified by age of diagnosis, grade and stage of disease, and evidence of linkage to the other loci to increase genetic homogeneity.

RESULTS

Age at diagnosis was the most correlated clinical trait within families. A maximum NPL score of 2.61 (P = 0.007) appeared to confirm HPC1 linkage for families that had a prevalence of high-grade or advanced-stage prostate cancer and which were not likely to be linked to PCaP, HPCX, or CAPB. Because the NPL scores improved when families more likely to be linked to the other loci were excluded, HPC1 may act independently of the other loci. The relationship of HPC1 and aggressive disease was strongest in families with median age at diagnosis > or =65 years (NPL, 3.48; P = 0.0008).

CONCLUSIONS

The current results suggest that HPC1 linkage may be most common among families with more severe prostate cancer. Stratification by clinical characteristics may be a useful tool in prostate cancer linkage analyses and may increase our understanding of hereditary prostate cancer.

Optimal cell source for cardiovascular tissue engineering: venous vs. aortic human myofibroblasts

Arterial vascular cells have been successfully utilized for tissue engineering in human cardiovascular structures, such as heart valves. The present study evaluates saphenous vein-derived myofibroblasts as an alternative, easy-to-access cell source for human cardiovascular tissue engineering. Biodegradable polyurethane scaffolds were seeded with human vascular myofibroblasts. Group A consisted of scaffolds seeded with cells from ascending aortic tissue; in group B, saphenous vein-derived cells were used. Analysis included histology, electron microscopy, mechanical testing, and biochemical assays for cell proliferation (DNA) and extracellular matrix (collagen). DNA content was comparable in both groups. Collagen and stress at maximum load was significantly higher in group B. Morphology showed viable, layered cellular tissue in all samples, with collagen fibrils most pronounced in group B. In conclusion, saphenous vein myofibroblasts cultured on biodegradable scaffolds showed excellent in vitro tissue generation. Collagen formation and mechanical properties were superior to aortic tissue derived constructs. Therefore, the easy-to-access vein cells represent a promising alternative cell source for cardiovascular tissue engineering.