17 research outputs found
Courting virtual rivals increase ejaculate size in sticklebacks ( Gasterosteus aculeatus )
Sperm competition occurs when sperm of two or more males compete to fertilize a given set of eggs. Game-theory models of sperm competition predict that males, which face an increased risk of sperm competition, will invest more sperm in a mating. In the pair-spawning three-spined stickleback (Gasterosteus aculeatus), males attempt to steal fertilizations (i.e. to sneak) when they are in the courting phase, but not when they are parental. The behaviour of neighbouring males may therefore indicate the risk of sperm competition. We visually confronted males before spawning with computer animations of the same virtual stickleback showing two different behaviours: either courting (high risk of sperm competition) or brood-caring (low risk of sperm competition). We show that males invest significantly more sperm (absolutely and relatively with respect to available sperm in the testes) after the courting stimulus. The relative investment ratio between the courting and the brood-caring treatment was on average 1.75. Three-spined sticklebacks thus seem to assess the risk of sperm competition by the behaviour of neighbours and to adjust their ejaculate accordingly. This result suggests that the evolutionary force of sperm competition has led to precise mechanisms of future risk assessmen
IVDR: Analysis of the Social, Economic, and Practical Consequences of the Application of an Ordinance of the In Vitro Diagnostic Ordinance in Switzerland
IVDR regulation represents a major challenge for diagnostic microbiology laboratories. IVDR complicates a broad range of aspects and poses a risk given the high diversity of pathogens (including rare but highly virulent microbes) and the large variety of samples submitted for analysis. The regular emergence of new pathogens (including Echovirus E-11, Adenovirus 41, Monkeypox virus, Alongshan virus, and Enterovirus D68, as recent examples in Europe in the post SARS-CoV-2 era) is another factor that makes IVDR regulation risky, because its detrimental effect on production of in-house tests will negatively impact knowledge and expertise in the development of new diagnostic tests. Moreover, such regulations negatively impact the availability of diagnostic tests, especially for neglected pathogens, and has a detrimental effect on the overall costs of the tests. The increased regulatory burden of IVDR may thereby pose an important risk for public health. Taken together, it will have a negative impact on the financial balance of diagnostic microbiology laboratories (especially small ones). The already-high standards of quality management of all ISO-accredited and Swissmedic-authorized laboratories render IVDR law of little value, at least in Switzerland, while tremendously increasing the regulatory burden and associated costs. Eventually, patients will need to pay for diagnostic assays outside of the framework of their insurance in order to obtain a proper diagnostic assessment, which may result in social inequity. Thus, based on the risk assessment outlined above, the coordinated commission for clinical microbiology proposes adjusting the IvDO ordinance by (i) introducing an obligation to be ISO 15189 accredited and (ii) not implementing the IvDO 2028 milestone
Aerococcus urinae and Aerococcus sanguinicola:Susceptibility Testing of 120 Isolates to Six Antimicrobial Agents Using Disk Diffusion (EUCAST), Etest, and Broth Microdilution Techniques
Altering lamina assembly reveals lamina-dependent and -independent functions for A-type lamins
Lamins are intermediate filament proteins that form a fibrous meshwork, called the nuclear lamina, between the inner nuclear membrane and peripheral heterochromatin of metazoan cells. The assembly and incorporation of lamin A/C into the lamina, as well as their various functions, are still not well understood. Here, we employed designed ankyrin repeat proteins (DARPins) as new experimental tools for lamin research. We screened for DARPins that specifically bound to lamin A/C, and interfered with lamin assembly in vitro and with incorporation of lamin A/C into the native lamina in living cells. The selected DARPins inhibited lamin assembly and delocalized A-type lamins to the nucleoplasm without modifying lamin expression levels or the amino acid sequence. Using these lamin binders, we demonstrate the importance of proper integration of lamin A/C into the lamina for nuclear mechanical properties and nuclear envelope integrity. Finally, our study provides evidence for cell-type-specific differences in lamin functions
Simultaneous quantification of five bacterial and plant toxins from complex matrices using a multiplexed fluorescent magnetic suspension assay
Proteotoxins such as ricin, abrin, botulinum neurotoxins type A and B (BoNT/A, BoNT/B) and staphylococcal enterotoxin B (SEB) are regarded as potential biological warfare agents which could be used for bioterrorism attacks on the food chain. In this study we used a novel immunisation strategy to generate high-affinity monoclonal and polyclonal antibodies against native ricin, BoNT/A, and BoNT/B. The antibodies were used along with antibodies against SEB and abrin to establish a highly sensitive magnetic and fluorescent multiplex bead array with excellent sensitivities between 2 ng/L and 546 ng/L from a minimal sample volume of 50 µL. The assay was validated using 20 different related analytes and the assay precision was determined. Advancing the existing bead array technology, the novel magnetic and fluorescent microbeads proved amenable to enrichment procedures, by further increasing sensitivity to 0.3–85 ng/L, starting from a sample volume of 500 µL. Furthermore, the method was successfully applied for the simultaneous identification of the target toxins spiked into complex food matrices like milk, baby food and yoghurt. On the basis of our results, the assay appears to be a good tool for large-scale screening of samples from the food supply chain
Courting virtual rivals increase ejaculate size in sticklebacks ( Gasterosteus aculeatus )
Alpha-defensin lateral flow test does not appear to be useful in predicting shoulder periprosthetic joint infections
PURPOSE: Periprosthetic joint infections (PJIs) remain a challenging complication after shoulder arthroplasty. The antimicrobial peptide α-defensin has been proposed as a new synovial fluid biomarker in diagnosing PJIs. To date, only little data are available on the diagnostic accuracy of α-defensin in shoulder PJIs; thus, we aimed to evaluate its diagnostic value in a cohort of patients with a suspected shoulder PJI.
METHODS: Between June 2016 and June 2018, we prospectively enrolled patients with a diagnostic shoulder aspiration due to painful shoulder arthroplasty or planned revision surgery. PJI diagnostics were performed according to the Musculoskeletal Infection Society (MSIS) criteria. All patients with an antibiotic therapy within two weeks before enrollment, insufficient amount of synovial aspirate, or bloody aspiration were excluded. α-Defensin was measured in the synovial fluid using the α-defensin lateral flow (ADLF) test (Synovasure®).
RESULTS: Out of 60 patients, we could include 29 (59% female) patients with a mean age of 70 (range, 50-92) years. A shoulder PJI was detected in five cases (Staphylococcus aureus, n = 2; Staphylococcus epidermidis, n = 2; Cutibacterium acnes, n = 1). The ADLF test was positive in seven out of 29 cases. According to the MSIS criteria, the ADLF test was false-negative in two patients and false-positive in four patients, resulting in sensitivity, specificity, and positive and negative predictive value of 60%, 83%, 43%, and 91%, respectively. The overall accuracy was 79%.
CONCLUSION: The ALDF test does not appear to be useful in predicting shoulder PJIs but may be used as an additional diagnostic factor in rejecting these infections