183 research outputs found
The effectiveness of a large protected area to conserve a global endemism hotspot may vanish in the face of climate and land-use changes
Endemic vertebrates are a crucial component of biodiversity, yet face disproportionally high extinction risk as climate and land-use changes drive habitat loss. Large protected areas are therefore deemed necessary to mitigate biodiversity loss. In 2021, China's Giant Panda National Park (GPNP, 27,134 km(2)) was established in one of the global endemism hotspots. In this study we ask the question whether this large national park is able to conserve the many threatened endemic vertebrates occurring in the region in the face of climate and land-use changes, in order to assess the long-term effectiveness of the GPNP. We used species distribution modeling techniques to project the distributions of 40 threatened terrestrial (and freshwater) endemic vertebrates under land-use and climate change scenarios SSP2-4.5, SSP3-7.0 and SSP5-8.5 in 2081-2100, and assessed the extent to which their distributions are covered by the GPNP, now and in the future. We found that by 2081-2100, two thirds of the threatened endemic vertebrates are predicted to lose part (15-79%, N = 4) of or (nearly) their entire (80-100% loss, N = 23) range under all three climate and land-use change scenarios. Consequently, fewer species are predicted to occur in the GPNP than at present. Our findings confirm the high vulnerability of threatened endemic species to climate and land-use changes, despite protected areas. Habitat loss due to climate and land-use changes elevate extinction risk of species in endemism hotspots across the globe. Urgent, widespread and intensified mitigation measures and adaptation measures are required at a landscape scale for effective conservation efforts in the future
Time-trends in disease characteristics and comorbidities in patients with chronic hepatitis B in the period 1980–2020
Background & aims: The incidence of chronic hepatitis B (CHB) is declining due to successful implementation of vaccination programs and widespread use of antiviral therapy. We aimed to study time-trends in disease characteristics and comorbidities in newly referred CHB patients. Methods: : We collected information on hepatitis B virus (HBV) related disease characteristics (including hepatitis B e-antigen (HBeAg) status, viremia, stage of liver fibrosis and indication for treatment and/or hepatocellular carcinoma (HCC) surveillance) and presence of comorbidities in all CHB patients referred to our center from 1980 through 2020. Patient characteristics were compared according to referral date (before 2000, between 2000 and 2010 and after 2010). Results: : We identified 1515 eligible patients. Patients referred after 2010 were older (36 versus 34 years, p < 0.001), more often non-Caucasian (82.3% versus 55.0%, p < 0.001) and more frequently HBeAg negative (81.5% versus 49.8%, p < 0.001) when compared to patients referred before 2000. Adjusted for ethnicity, sex and age, patients referred after 2010 were less likely to have significant fibrosis (adjusted odds ratio [aOR]:0.178, p < 0.001) or indication for antiviral therapy (aOR:0.342, p < 0.001) but were more likely to be affected by the metabolic syndrome (aOR:1.985, p = 0.013), hepatic steatosis (aOR:1.727, p < 0.001) and metabolic dysfunction associated fatty liver disease (MAFLD) (aOR:1.438, p = 0.013). Conclusions: : The characteristics of the CHB populations are changing. Newly referred patients are older, have less active HBV related liver disease but are more likely to be co-affected by MAFLD. These findings provide guidance for adequate allocation of resources to cope with the changing characteristics of the CHB population
Long-term effects of treatment and response in patients with chronic hepatitis C on quality of life. An international, multicenter, randomized, controlled study
Background: Hepatitis C decreases health related quality of life (HRQL) which is further diminished by antiviral therapy. HRQL improves after successful treatment. This trial explores the course of and factors associated with HRQL in patients given individualized or standard treatment based on early treatment response (Ditto-study).
Methods: The Short Form (SF)-36 Health Survey was administered at baseline (n = 192) and 24 weeks after the end of therapy (n = 128).
Results: At baseline HRQL was influenced by age, participating center, severity of liver disease and income. Exploring the course of HRQL (scores at follow up minus baseline), only the dimension general health increased. In this dimension patients with a relapse or sustained response differed from non-responders. Men and women differed in the dimension bodily pain. Treatment schedule did not influence the course of HRQL.
Conclusions: Main determinants of HRQL were severity of liver disease, age, gender, participating center and response to treatment. Our results do not exclude a more profound negative impact of individualized treatment compared to standard, possibly caused by higher doses and extended treatment duration in the individualized group. Antiviral therapy might have a more intense and more prolonged negative impact on females
Dynamics of interferon-gamma release assay and cytokine profiles in blood and respiratory tract specimens from mice with tuberculosis and the effect of therapy
There are limitations on diagnostic methods to differentiate between active and latent tuberculosis (TB), and the prediction of latent progression to TB disease is yet complex. Traditionally, tuberculosis-specific host immune response was visualized using the tuberculin skin test. Nowadays, IFN-γ release assays (IGRA) provide a more specific and sensitive tool, by which exposure to Mtb could be determined. However, the merit of IGRA aids in diagnosing active TB is yet unclear. We adapted IGRA for use in mice, and quantifying bead-based flow cytometry techniques were used to assess cytokine profiles during the course of untreated infection and to investigate the value of IGRA and cytokines as biomarkers for therapy response. High variability of IGRA results during progression of active TB infection related to various phases of infection was obtained. However, a significant decrease in IGRA results and in levels of IFN-γ, IL-17, IP-10 or MIG was observed and appeared to be associated with successful therapy. This outcome does not support the value of IGRA to accurately diagnose active TB or to monitor infection progression. However, IGRA proved to be a useful biomarker to monitor therapy success. In addition, different cytokines might serve as biomarkers
Natuurverkenning 2010-2040 : visies op de ontwikkeling van natuur en landschap
De Natuurverkenning verschijnt in een turbulente tijd waarin natuur en landschap sterk gepolitiseerd zijn. Met de verkenning wil het PBL een bijdrage leveren aan het structureren van het debat over de vernieuwing van het langetermijnbeleid en een impuls geven aan de politieke afwegingen. Nieuw is het gebruik van normatieve toekomstscenario’s als hulpmiddel om de achterliggende drijfveren voor natuurbeleid te verhelderen
Activated CD4(+) T cells and highly differentiated alloreactive CD4(+) T cells distinguish operationally tolerant liver transplantation recipients
Spontaneous operational tolerance to the allograft develops in a proportion of liver transplantation (LT) recipients weaned off immunosuppressive (IS) drugs. Several studies have investigated whether peripheral blood circulating T cells could play a role in the development or identify operational tolerance, but never characterized alloreactive T cells in detail due to the lack of a marker for these T cells. In this study, we comprehensively investigated phenotypic and functional characteristics of alloreactive circulating T cell subsets in tolerant LT recipients (n = 15) using multiparameter flow cytometry and compared these with LT recipients on IS drugs (n = 23) and healthy individuals (n = 16). Activation-induced CD137 was used as a marker for alloreactive T cells upon allogenic stimulation. We found that central and effector memory CD4+ T cells were hyporesponsive against donor and third-party splenocyte stimulation in tolerant LT recipients, whereas an overall hyperresponsiveness was observed in alloreactive terminally differentiated effector memory CD4+ T cells. In addition, elevated percentages of circulating activated T helper cells were observed in these recipients. Lastly, tolerant and control LT recipients did not differ in donor-specific antibody formation. In conclusion, a combination of circulating hyperresponsive highly differentiated alloreactive CD4+ T cells and circulating activated T helper cells could discriminate tolerant recipients from a larger group of LT recipients.Transplantation and autoimmunit
Animal Perception of Seasonal Thresholds: Changes in Elephant Movement in Relation to Rainfall Patterns
Background: The identification of temporal thresholds or shifts in animal movement informs ecologists of changes in an animal\u2019s behaviour, which contributes to an understanding of species\u2019 responses in different environments.
In African savannas, rainfall, temperature and primary productivity influence the movements of large herbivores
and drive changes at different scales. Here, we developed a novel approach to define seasonal shifts in movement
behaviour by examining the movements of a highly mobile herbivore (elephant; Loxodonta africana), in relation to
local and regional rainfall patterns.
Methodology/Principal Findings: We used speed to determine movement changes of between 8 and 14 GPS-collared
elephant cows, grouped into five spatial clusters, in Kruger National Park, South Africa. To detect broad-scale
patterns of movement, we ran a three-year daily time-series model for each individual (2007\u20132009). Piecewise
regression models provided the best fit for elephant movement, which exhibited a segmented, waveform pattern
over time. Major breakpoints in speed occurred at the end of the dry and wet seasons of each year. During the
dry season, female elephant are constrained by limited forage and thus the distances they cover are shorter and
less variable. Despite the inter-annual variability of rainfall, speed breakpoints were strongly correlated with
both local and regional rainfall breakpoints across all three years. Thus, at a multi-year scale, rainfall
patterns significantly affect the movements of elephant. The variability of both speed and rainfall breakpoints
across different years highlights the need for an objective definition of seasonal boundaries.
Conclusions/Significance: By using objective criteria to determine behavioural shifts, we identified a
biologically meaningful indicator of major changes in animal behaviour in different years. We recommend the use of such criteria, from an animal\u2019s perspective, for delineating seasons or other extrinsic shifts in ecological studies, rather than arbitrarily fixed definitions based on convention or common practice
BioScore: A tool to assess the impacts of European Community policies on Europe's biodiversity
BioScore offers a European biodiversity impact assessment tool. The tool contains indicator values on the ecological preferences of more than 1000 species of birds, mammals, amphibians, reptiles, fish, butterflies, dragonflies, aquatic macro-invertebrates and vascular plants. These values are linked to policy-related pressures and environmental variables
Beoordeling natuurakkoord : globale toetsing van het onderhandelingsakkoord decentralisatie natuur
Het Planbureau voor de Leefomgeving (PBL) heeft op verzoek van het kabinet het ‘Onderhandelingsakkoord decentralisatie natuur’ getoetst. Het Rijk draagt, met het van kracht worden van dit akkoord, het natuurbeleid over aan de provincies. Daarvoor voegt het Rijk jaarlijks 100 miljoen euro toe aan het Provinciefonds. Een belangrijk onderdeel van dat beleid, de Ecologische Hoofdstructuur (EHS), wordt in 2021 afgerond, maar zal dan kleiner van omvang zijn dan oorspronkelijk gepland. De provincies worden verantwoordelijk voor het beheer van de EHS. Met al deze wijzigingen vermindert het Rijk zijn uitgaven voor natuur en landschap met twee derde deel. De vraag die het kabinet aan het PBL heeft gesteld, is of Nederland met de uitvoering van het akkoord en de voorgestelde bezuinigingen kan voldoen aan de internationale verplichtingen en doelstellingen, die voortvloeien uit onder andere de Europese Vogel- en Habitatrichtlijnen
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