50 research outputs found
Expression of key ion transporters in the gill and esophageal- gastrointestinal tract of euryhaline mozambique tilapia oreochromis mossambicus acclimated to fresh water, seawater and hypersaline water
10.1371/journal.pone.0087591PLoS ONE91-POLN
Glucosamine increases hyaluronic acid production in human osteoarthritic synovium explants
Background. Glucosamine (GlcN) used by patients with osteoarthritis was demonstrated to reduce pain, but the working mechanism is still not clear. Viscosupplementation with hyaluronic acid (HA) is also described to reduce pain in osteoarthritis. The synthesis of HA requires GlcN as one of its main building blocks. We therefore hypothesized that addition of GlcN might increase HA production by synovium tissue. Methods. Human osteoarthritic synovium explants were obtained at total knee surgery and pre-cultured for 1 day. The experimental conditions consisted of a 2 days continuation of the culture with addition of N-Acetyl-glucosamine (GlcN-Ac; 5 mM), glucosamine-hydrochloride (GlcN-HCl; 0.5 and 5 mM), glucose (Gluc; 0.5 and 5 mM). Hereafter HA production was measured in culture medium supernatant using an enzyme-linked binding protein assay. Real time RT-PCR was performed for hyaluronic acid synthase (HAS) 1, 2 and 3 on RNA isolated from the explants. Results. 0.5 mM
Comparison between two different experimental models of osteoarthritis in rabbits. Intra-articular collagenase injection and anterior cruciate ligament transection
A community-sourced glossary of open scholarship terms
Supplementary Information: This list of terms represents the ‘Open Scholarship Glossary 1.0’ (available at: https://forrt.org/glossary/. Glossary available under a CC BY NC SA 4.0 license at: https://static-content.springer.com/esm/art%3A10.1038%2Fs41562-021-01269-4/MediaObjects/41562_2021_1269_MOESM1_ESM.pdf).https://static-content.springer.com/esm/art%3A10.1038%2Fs41562-021-01269-4/MediaObjects/41562_2021_1269_MOESM1_ESM.pd
Predicting predatory impact of juvenile invasive lionfish (Pterois volitans) on a crustacean prey using functional response analysis: effects of temperature, habitat complexity and light regimes
The ecological implications of biotic interactions, such as predator-prey relationships, are often context-dependent. Comparative functional responses analysis can be used under different abiotic contexts to improve understanding and prediction of the ecological impact of invasive species. Pterois volitans (Lionfish) [Linnaeus 1758] is an established invasive species in the Caribbean and Gulf of Mexico, with a more recent invasion into the Mediterranean. Lionfish are generalist predators that impact a wide range of commercial and non-commercial species. Functional response analysis was employed to quantify interaction strength between lionfish and a generic prey species, the shrimp (Paleomonetes varians) [Leach 1814], under the contexts of differing temperature, habitat complexity and light wavelength. Lionfish have prey population destabilising Type II functional responses under all contexts examined. Significantly more prey were consumed at 26 °C than at 22 °C. Habitat complexity did not significantly alter the functional response parameters. Significantly more prey were consumed under white light and blue light than under red light. Attack rate was significantly higher under white light than under blue or red light. Light wavelength did not significantly change handling times. The impacts on prey populations through feeding rates may increase with concomitant temperature increase. As attack rates are very high at low habitat complexity this may elucidate the cause of high impact upon degraded reef ecosystems with low-density prey populations, although there was little protection conferred through habitat complexity. Only red light (i.e. dark) afforded any reduction in predation pressure. Management initiatives should account for these environmental factors when planning mitigation and prevention strategies
Cigarette taxation and price differentials in 195 countries during 2014-2018
INTRODUCTION: Raising tobacco prices via increased taxation may be undermined by tobacco industry tactics to keep budget cigarettes on the market. Price differentials between budget and premium cigarettes allow smokers to trade down in the face of average price rises thus attenuating health benefits. This study examines global trends of price differentials and associations with taxation. METHODS: Ecological analysis of country-level panel data of 195 countries' price differentials was performed and compared against total, specific excise, ad valorem and other taxation. Price differentials were expressed as the difference between budget cigarette and premium pack prices (as % of premium pack prices). Two-level linear regression models with repeated measurements (2014, 2016 and 2018) nested within each country assessed the association between country-level taxation structures and price differentials, adjusted for year, geographical region and income group. RESULTS: Worldwide, median price differential between budget and premium 20-cigarette packs was 49.4% (IQR 25.9%-70.0%) in 2014 and 44.4% (IQR 22.5%-69.4%) in 2018 with significant regional variation. The largest price differentials in 2018 were in Africa, with the lowest in Europe. Total taxation was negatively associated with price differentials (-1.5%, 95% CI -2.5% to -0.4% per +10% total taxation) as was specific excise taxation (-2.5%, 95% CI -3.7% to -1.2% per +10% specific excise tax). We found no statistically significant association between ad valorem taxation and price differentials. CONCLUSION: Total levels of taxation and specific excise taxes were associated with smaller price differentials. Implementing high specific excise taxes may reduce price differentials and improve health outcomes