48 research outputs found
Tree species traits but not diversity mitigate stem breakage in a subtropical forest following a rare and extreme ice storm
Peer reviewedPublisher PD
Improving mental well-being in psychocardiology—a feasibility trial for a non-blended web application as a brief metacognitive-based intervention in cardiovascular disease patients
Background: Many patients with cardiovascular disease also show a high comorbidity of mental disorders, especially such as anxiety and depression. This is, in turn, associated with a decrease in the quality of life. Psychocardiological treatment options are currently limited. Hence, there is a need for novel and accessible psychological help. Recently, we demonstrated that a brief face-to-face metacognitive therapy (MCT) based intervention is promising in treating anxiety and depression. Here, we aim to translate the face-to-face approach into digital application and explore the feasibility of this approach. Methods: We translated a validated brief psychocardiological intervention into a novel non-blended web app. The data of 18 patients suffering from various cardiac conditions but without diagnosed mental illness were analyzed after using the web app over a two-week period in a feasibility trial. The aim was whether a non-blended web app based MCT approach is feasible in the group of cardiovascular patients with cardiovascular disease. Results: Overall, patients were able to use the web app and rated it as satisfactory and beneficial. In addition, there was first indication that using the app improved the cardiac patients’ subjectively perceived health and reduced their anxiety. Therefore, the approach seems feasible for a future randomized controlled trial. Conclusion: Applying a metacognitive-based brief intervention via a non-blended web app seems to show good acceptance and feasibility in a small target group of patients with CVD. Future studies should further develop, improve and validate digital psychotherapy approaches, especially in patient groups with a lack of access to standard psychotherapeutic care
Symptoms and Needs of Patients with Advanced Lung Cancer: Early Prevalence Assessment
Background: Little is known on symptom burden, psychosocial
needs, and perception of prognosis in advanced lung
cancer patients at the time of diagnosis, although early assessment
is strongly recommended within the setting of daily
routine care. Methods: Twelve study sites cross-sectionally
assessed symptoms and psychosocial needs of patients
suffering from newly diagnosed incurable lung cancer. Assessment
comprised NCCN distress thermometer, FACT-L,
SEIQoL-Q, PHQ-4, and shortened and modified SCNS-SF-34
questionnaires. Additional prognostic information from
both patients and physicians were collected. Results: A total
of 208 patients were evaluated. Mean age was 63.6 years,
58% were male, 84% suffered from stage IV lung cancer, and
71% had an ECOG performance status of 0–1. Mean distress
level was 5.4 (SD 2.5), FACT-L total score was 86 (21.5), and
TOI 50.5 (14.9). PHQ-4 was 4.6 (3.3), and shortened and modified
SCNS-SF-34 showed 9 (8.7) unmet needs per patient.
According to their physicians’ perspective, 98.1% of patients
were reflecting on and 85.2% were accepting incurability,
while 26.5% of patients considered the treatment to be of
curative intent. Conclusion: Our findings emphasize substantial
domains of symptom burden seen in newly diagnosed,
incurable lung cancer patients. Oncologists should
be aware of these features and address prognostic issues early in the disease trajectory to facilitate opportunities to
improve coping, advance care planning, and appropriate integration
of palliative care, thus improving quality of life
Neighbourhood species richness and drought-tolerance traits modulate tree growth and δ13C responses to drought
Mixed-species forests are promoted as a forest management strategy for climate change mitigation and adaptation because they are more productive and can be more resistant and resilient than monospecific forests under drought stress. However, the trait-based mechanisms driving these properties remain elusive, making it difficult to predict which functional identities of species best improve tree growth and decrease tree physiological water stress under drought. We investigated tree growth and physiological stress responses (i.e. increase in wood carbon isotopic ratio; δ13C) to changes in climate-induced water availability (wet-to-dry years) along gradients in neighbourhood tree species richness and drought-tolerance traits. Using tree cores from a large-scale biodiversity experiment, we tested the overarching hypothesis that neighbourhood species richness increases growth and decreases δ13C. We further hypothesized that the abiotic (i.e. climatic conditions) and the biotic context modulate these biodiversity-ecosystem functioning relationships. We characterized the biotic context using drought-tolerance traits of focal trees and their neighbours. These traits are related to cavitation resistance vs. resource acquisition and stomatal control. We found that tree growth increased with neighbourhood species richness. However, we did not observe a universal relief of water stress in species-rich neighbourhoods, nor an increase in the strength of the relationship between richness and growth and between richness and δ13C from wet-to-dry years. Instead, these relationships depended on both the traits of the focal trees and their neighbours. At either end of each drought-tolerance gradient, species responded in opposing directions during drought and non-drought years. Synthesis. We report that the biotic context can determine the strength and nature of biodiversity-ecosystem functioning relationships in experimental tree communities. We derive two key conclusions: (1) drought-tolerance traits of focal trees and their neighbours can explain divergent tree responses to drought and diversity, and (2) contrasting, trait-driven responses of tree species to wet vs dry climatic conditions can promote forest community stability. Mixing tree species with a range of drought-tolerance traits may therefore increase forest productivity and stability
Termite sensitivity to temperature affects global wood decay rates.
Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface
Hexokinase II integrates energy metabolism and cell survival regulation
Ziel der vorliegenden Arbeit war es die molekularen Mechanismen der
neuroprotektiven Wirkung der Hexokinase II in einem in vitro Modell der
zerebralen Ischämie zu untersuchen. Klassischerweise gehört die Hexokinase II
(HKII) zu den vier Hexokinase Isoenzymen, die den ersten obligatorischen
Schritt im Glukosestoffwechsel von Säugetieren katalysieren. Neben ihrer
zentralen Rolle im Energiemetabolismus kommt der HKII eine funktionelle
Bedeutung innerhalb der Apoptoseregulation zu. Zur Charakterisierung der
neuroprotektiven Eigenschaften der HKII wurden Expressionsvektoren mit
Punktmutationen in bereits bekannte, funktionell und strukturell wichtige HKII
Domänen generiert, in eine primäre Neuronenkultur transfiziert und im Rahmen
der kombinierten Sauerstoff- und Glukose-Deprivation (OGD) beziehungsweise
reinen Sauerstoff-Deprivation (OD) oder Glukose-Deprivation (GD) auf ihre
antiapoptotischen Effekte getestet. Die Ergebnisse demonstrieren die
essentielle Bedeutung der mitochondrialen HKII-Bindung für die Vermittlung des
neuronalen Zellschutzes im OGD-Modell, dargestellt durch die Aufhebung der
protektiven Effekte bei Überexpression einer mitochondrialen
Lokalisationssequenz defizienten HKII Mutante. Durch funktionelle Testung
einer Akt-Phosphorylierungsdefizienten HKII Mutante und Akt-Phosphomimetischen
HKII Mutante konnte eine apoptose-regulatorische Wirkung des HKII-Akt-
Phosphorylierungsmotifs unter hypoxischen Bedingungen nachgewiesen werden. Der
negative Effekt der HKII-BH-4 Domäne inaktivierten Mutante auf das
Neuronenüberleben bestätigt die Funktionalität einer im C-Terminus des HKII
Proteins postulierten HKII-BH-4 Domäne. In Zellkulturexperimenten mit einer
katalytisch-inaktiven HKII Doppelmutante zeigte sich eine Glukoseabhängigkeit
der antiapoptotischen Eigenschaften der HKII. Die katalytische Aktivität der
HKII ist maßgeblich an der zellschützenden Wirkung des glykolytischen Enzyms
beteiligt und macht die HKII zu einem interessanten Verknüpfungspunkt zwischen
Zellmetabolismus und Apoptoseregulation. Durch die strukturell-funktionelle
Charakterisierung der HKII-vermittelten Neuroprotektion erschließt sich ein
besseres Verständnis der ablaufenden molekularen Mechanismen innerhalb der
Apoptoseregulation. Diese Erkenntnisse bieten einen gezielteren Ansatz für die
Identifizierung und Entwicklung von neuen Wirkstofftargets zur Therapie von
neurodegenerativen- und Tumorerkrankungen. Da die HK neben ihrer ubiquitären
Expression eine allgemein große Bedeutung für den Glukosemetabolismus in
Säugetierzellen hat, könnten die nachgewiesenen funktionell- wichtigen HKII
Domänen auch über neuronale Zellen hinaus relevant sein und beispielsweise zur
Therapieoptimierung bei einem Myokardinfarkt beitragen.Hexokinase II (HKII) is one of 4 mammalian Hexokinase isoenzymes catalyzing
the first obligatory step of glucose metabolism. In addition to their
catalytical activity, HKII is also believed to play a role in regulating cell
death. In the state of ischemic tolerance Hexokinase II is upregulated by
Hypoxia inducible factor 1 (HIF-1). In order to investigate the role of HKII
in neuroprotective signaling, site directed mutagenesis was used to generate
several murine HKII expression vectors with mutations in domains relevant for
glucose metabolism and apoptosis regulation. The effect of HKII and its
mutants on neuronal survival was studied using a sensitive technique based on
co-transfecting embryonic rat primary cortical neurons with eGFP (green cells)
and HKII or HKII mutant vectors. These co-transfected cells were co-cultivated
with primary neurons expressing m-orange (orange cells) and subsequently
submitted to an in vitro model of cerebral ischemia (oxygen-glucose-
deprivation, OGD), (glucose-deprivation, GD) or (oxygen-deprivation, OD),
respectively. The ratio of green vs. orange neurons before and after the
damaging event was analysed. Thereby the effect of different HKII mutants on
neuronal survival could be determined. The data demonstrates that
mitochondrial binding of HKII is a dynamic and adaptive response mediated by
protein kinase B (PKB)/Akt kinase dependent phosphorylation, that protects
neurons from OGD induced apoptosis. It is proposed that HKII may serve as a
molecular switch regulating apoptosis in a glucose concentration depending
fashion and may those provide a link between cellular metabolism and survival.
These results might also have a therapeutic implication for vascualar diseases
like stroke