64 research outputs found
Peri-Operative Kinetics of Plasma Mitochondrial DNA Levels during Living Donor Kidney Transplantation
During ischemia and reperfusion injury (IRI), mitochondria may release mitochondrial DNA (mtDNA). mtDNA can serve as a propagator of further injury but in specific settings has anti-inflammatory capacities as well. Therefore, the aim of this study was to study the perioperative dynamics of plasma mtDNA during living donor kidney transplantation (LDKT) and its potential as a marker of graft outcome. Fifty-six donor-recipient couples from the Volatile Anesthetic Protection of Renal Transplants-1 (VAPOR-1) trial were included. Systemic venous, systemic arterial, and renal venous samples were taken at multiple timepoints during and after LDKT. Levels of mtDNA genes changed over time and between vascular compartments. Several donor, recipient, and transplantation-related variables significantly explained the course of mtDNA genes over time. mtDNA genes predicted 1-month and 24-month estimated glomerular filtration rate (eGFR) and acute rejection episodes in the two-year follow-up period. To conclude, mtDNA is released in plasma during the process of LDKT, either from the kidney or from the whole body in response to transplantation. While circulating mtDNA levels positively and negatively predict post-transplantation outcomes, the exact mechanisms and difference between mtDNA genes are not yet understood and need further exploration.</p
Homozygous whole body Cbs knockout in adult mice features minimal pathology during ageing despite severe homocysteinemia
Deficiencies in Cystathionine-β-synthase (CBS) lead to hyperhomocysteinemia (HHCy), which is considered a risk factor for cardiovascular, bone and neurological disease. Moreover, CBS is important for the production of cysteine, hydrogen sulfide (H2 S) and glutathione. Studying the biological role of CBS in adult mice has been severely hampered by embryological disturbances and perinatal mortality. To overcome these issues and assess the effects of whole-body CBS deficiency in adult mice, we engineered and characterized a Cre-inducible Cbs knockout model during ageing. No perinatal mortality occurred before Cbs-/- induction at 10 weeks of age. Mice were followed until 90 weeks of age and ablation of Cbs was confirmed in liver and kidney but not in brain. Severe HHCy was observed in Cbs-/- (289 ± 58 µM) but not in Cbs+/- or control mice (<10 µM). Cbs-/- showed impaired growth, facial alopecia, endothelial dysfunction in absence of increased mortality, and signs of liver or kidney damage. CBS expression in skin localized to sebaceous glands and epidermis, suggesting local effects of Cbs-/- on alopecia. Cbs-/- showed increased markers of oxidative stress and senescence but expression of other H2 S producing enzymes (CSE and 3-MST) was not affected. CBS deficiency severely impaired H2 S production capacity in liver, but not in brain or kidney. In summary, Cbs-/- mice presented a mild phenotype without mortality despite severe HHCy. The findings demonstrate that HHCy is not directly linked to development of end organ damage
Forest biodiversity, carbon sequestration, and wood production: modeling synergies and trade-offs for ten forest landscapes across Europe
Original ResearchEurope’s forests provide vital habitat for biodiversity and essential ecosystem services
whose provision must be sustained or enhanced over the coming century. However,
the potential to secure or increase forest ecosystem services, while securing the
habitat requirements of taxa remains unclear, especially within the context of uncertain
climate and socio-economic developments. To tease out the associated trade-offs
and synergies, we used 10 case study landscapes within nine countries throughout
Europe. Starting with the current status of the forests in the case study landscapes,
we simulated forest development 100 years into the future. Simulations were embedded
in three combined climate and socio-economic frame scenarios based on global and
European policies which varied in their climate change mitigation efficiency. Scenarios
were translated into country specific projections of climate variables, and resultant
demands for wood products. Forest management regimes were projected to vary in
response to these scenarios at local scales. The specific combinations of alternative
forest management practices were based on parallel research and input from local forest
stakeholders. For each case study, a specific forest growth simulator was used. In
general, the climate scenarios applied did not cause fundamentally different ecosystem
service outputs at the case study level. Our results revealed almost no reduction in outcomes for biodiversity indicators with an increase in wood production, and in some
cases synergistic results occurred when diversity was actively promoted as part of the
management concept. Net carbon uptake was not strongly correlated with biodiversity,
indicating that biodiversity-friendly forest management doesn’t need to curtail carbon
sequestration. Notably, we obtained heterogeneous results for the relation between
sustainable wood production and net carbon uptake. Most scenarios resulted in a
more or less reduced net carbon uptake over the long term, often due to stand age
class distribution shifts. Levels of sustainable wood production varied widely during
the simulation period, from significant increases (Sweden, Lithuania) to minor changes
(Slovakia, Turkey) and slight decreases (Ireland, Netherlands). We place our results
within the larger context of European forest policy and the challenges of simulating and
contrasting forest biodiversity and the ecosystem services that societies depend on outcomes for biodiversity indicators with an increase in wood production, and in some
cases synergistic results occurred when diversity was actively promoted as part of the
management concept. Net carbon uptake was not strongly correlated with biodiversity,
indicating that biodiversity-friendly forest management doesn’t need to curtail carbon
sequestration. Notably, we obtained heterogeneous results for the relation between
sustainable wood production and net carbon uptake. Most scenarios resulted in a
more or less reduced net carbon uptake over the long term, often due to stand age
class distribution shifts. Levels of sustainable wood production varied widely during
the simulation period, from significant increases (Sweden, Lithuania) to minor changes
(Slovakia, Turkey) and slight decreases (Ireland, Netherlands). We place our results
within the larger context of European forest policy and the challenges of simulating and
contrasting forest biodiversity and the ecosystem services that societies depend oninfo:eu-repo/semantics/publishedVersio
HSPB1, HSPB6, HSPB7 and HSPB8 Protect against RhoA GTPase-Induced Remodeling in Tachypaced Atrial Myocytes
BACKGROUND: We previously demonstrated the small heat shock protein, HSPB1, to prevent tachycardia remodeling in in vitro and in vivo models for Atrial Fibrillation (AF). To gain insight into its mechanism of action, we examined the protective effect of all 10 members of the HSPB family on tachycardia remodeling. Furthermore, modulating effects of HSPB on RhoA GTPase activity and F-actin stress fiber formation were examined, as this pathway was found of prime importance in tachycardia remodeling events and the initiation of AF. METHODS AND RESULTS: Tachypacing (4 Hz) of HL-1 atrial myocytes significantly and progressively reduced the amplitude of Ca²⁺ transients (CaT). In addition to HSPB1, also overexpression of HSPB6, HSPB7 and HSPB8 protected against tachypacing-induced CaT reduction. The protective effect was independent of HSPB1. Moreover, tachypacing induced RhoA GTPase activity and caused F-actin stress fiber formation. The ROCK inhibitor Y27632 significantly prevented tachypacing-induced F-actin formation and CaT reductions, showing that RhoA activation is required for remodeling. Although all protective HSPB members prevented the formation of F-actin stress fibers, their mode of action differs. Whilst HSPB1, HSPB6 and HSPB7 acted via direct prevention of F-actin formation, HSPB8-protection was mediated via inhibition of RhoA GTPase activity. CONCLUSION: Overexpression of HSPB1, as well as HSPB6, HSPB7 and HSPB8 independently protect against tachycardia remodeling by attenuation of the RhoA GTPase pathway at different levels. The cardioprotective role for multiple HSPB members indicate a possible therapeutic benefit of compounds able to boost the expression of single or multiple members of the HSPB family
Оптимизация конструкции захвата для детали «Барабан»
Грузозахватные приспособления обычно применяются при производстве работ по подъему и перемещению грузов с применением грузоподъемных машин. Использование приспособлений позволяет реализовать максимальное удобство и безопасность производственного процесса. Грузозахватные приспособления конструируются для определенного этапа технологического процесса, для конкретного изделия. При проектировании таких приспособлений необходимо учитывать основные показатели оптимальности конструкции: прочность, надежность, простота, удобство и безопасность при эксплуатации, эргономичность. Кроме того, нужно стремиться к наименьшей массе и, соответственно, металлоемкости захвата. Конструкция грузозахватного приспособления, в основном, будет зависеть от назначенных технологом поверхностей, за которые можно крепиться и от максимальной высоты подъема крюка крана. В статье описана задача по конструированию захвата для детали «Барабан¬ в новом технологическом процессе. Рассмотрена конструкция существующего захвата, взятого за прототип. Приведен анализ различных вариантов конструктивных решений, созданных в процессе проектирования. Выбран вариант конструкции захвата, который в наибольшей степени соответствует требованиям технического задания. Конструкция этого модернизированного приспособления представляет собой захват с тремя лапами, удерживающими деталь, и подвес в виде траверсы. Разработанная конструкторская документация утверждена производством и отделом промышленной безопасности
Firm's Evaluation of Location Quality: Evidence from East Germany
Our study provides evidence for firms' evaluation of location quality. We use a 2004 survey of 6,000 East German firms that contained questions on the importance and assessment of 15 different location factors ranging from closeness to customers and suppliers, transport infrastructure, and proximity to research institutions and universities, as well as questions about the local financial institutions and region's 'image'. The results show (1) a great deal of heterogeneity in terms of which firm- or regional-level characteristics are important in the evaluation of a specific location factor, (2) that the model's explanatory power is, overall, low and thus neither location characteristics nor internal factors are fully reflected in the perceptions, (3) that a firm's business situation and whether a location factor is considered important have explanatory power for perception. One policy-relevant conclusion that we derive from these findings is that location policy should consider firms' perception of a specific location in addition to improving the actual attributes of that location
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