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991.
992.
Samantha K. Barton Timothy J. M. Moss Stuart B. Hooper Kelly J. Crossley Andrew W. Gill Martin Kluckow Valerie Zahra Flora Y. Wong Gerhard Pichler Robert Galinsky Suzanne L. Miller Mary Tolcos Graeme R. Polglase 《PloS one》2014,9(11)
Background
The onset of mechanical ventilation is a critical time for the initiation of cerebral white matter (WM) injury in preterm neonates, particularly if they are inadvertently exposed to high tidal volumes (VT) in the delivery room. Protective ventilation strategies at birth reduce ventilation-induced lung and brain inflammation and injury, however its efficacy in a compromised newborn is not known. Chorioamnionitis is a common antecedent of preterm birth, and increases the risk and severity of WM injury. We investigated the effects of high VT ventilation, after chorioamnionitis, on preterm lung and WM inflammation and injury, and whether a protective ventilation strategy could mitigate the response.Methods
Pregnant ewes (n = 18) received intra-amniotic lipopolysaccharide (LPS) 2 days before delivery, instrumentation and ventilation at 127±1 days gestation. Lambs were either immediately euthanased and used as unventilated controls (LPSUVC; n = 6), or were ventilated using an injurious high VT strategy (LPSINJ; n = 5) or a protective ventilation strategy (LPSPROT; n = 7) for a total of 90 min. Mean arterial pressure, heart rate and cerebral haemodynamics and oxygenation were measured continuously. Lungs and brains underwent molecular and histological assessment of inflammation and injury.Results
LPSINJ lambs had poorer oxygenation than LPSPROT lambs. Ventilation requirements and cardiopulmonary and systemic haemodynamics were not different between ventilation strategies. Compared to unventilated lambs, LPSINJ and LPSPROT lambs had increases in pro-inflammatory cytokine expression within the lungs and brain, and increased astrogliosis (p<0.02) and cell death (p<0.05) in the WM, which were equivalent in magnitude between groups.Conclusions
Ventilation after acute chorioamnionitis, irrespective of strategy used, increases haemodynamic instability and lung and cerebral inflammation and injury. Mechanical ventilation is a potential contributor to WM injury in infants exposed to chorioamnionitis. 相似文献993.
Gerhard Pichler Po-Yin Cheung Corinna Binder Megan O’Reilly Bernhard Schwaberger Khalid Aziz Berndt Urlesberger Georg M. Schm?lzer 《PloS one》2014,9(12)
Objective
To describe temporal changes in systolic, diastolic, and mean blood pressure (SBP, DBP, and MBP, respectively) in term and preterm infants immediately after birth.Methods
Prospective observational two-center study. In term infants SBP, DBP, and MBP were assessed non-invasively every minute for the first 15 minutes, and in preterm infants every minute for the first 15 minutes, as well as at 20, 25, 30, 45, and 60 minutes after birth. Regression analyses were performed by gender and respiratory support in all neonates; and by mode of delivery, cord clamping time, and development of ultrasound-detected brain injury in preterm neonates.Results
Term infants (n = 54) had a mean (SD) birth weight of 3298 (442) g and gestational age of 38 (1) weeks, and preterm infants (n = 94) weighed 1340 (672) g and were 30 (3) weeks gestation. Term infants’ SBP, DBP and MBP within the first 15 minutes after birth were independent of gender or respiratory support. Linear mixed regression analysis showed that preterm infants, who were female, born vaginally, had delayed cord clamping and did not require positive pressure ventilation nor develop periventricular injury or ventriculomegaly, had significantly higher SBP, DBP, and MBP at some measurement points within the first hour after birth.Conclusions
We present novel reference ranges of BP immediately after birth in a cohort of term and preterm neonates. They may aid in optimization of cardiovascular support during early transition at all gestations. 相似文献994.
Oliver K. Hauck Jana Scharnberg Nieves Medina Escobar Gerhard Wanner Patrick Giavalisco Claus-Peter Witte 《The Plant cell》2014,26(7):3090-3100
Purine nucleotides can be fully catabolized by plants to recycle nutrients. We have
isolated a urate oxidase (uox) mutant of
Arabidopsis thaliana that accumulates uric acid in all tissues,
especially in the developing embryo. The mutant displays a reduced germination rate
and is unable to establish autotrophic growth due to severe inhibition of cotyledon
development and nutrient mobilization from the lipid reserves in the cotyledons. The
uox mutant phenotype is suppressed in a xanthine
dehydrogenase (xdh) uox double mutant,
demonstrating that the underlying cause is not the defective purine base catabolism,
or the lack of UOX per se, but the elevated uric acid concentration in the embryo.
Remarkably, xanthine accumulates to similar levels in the xdh mutant
without toxicity. This is paralleled in humans, where hyperuricemia is associated
with many diseases whereas xanthinuria is asymptomatic. Searching for the molecular
cause of uric acid toxicity, we discovered a local defect of peroxisomes
(glyoxysomes) mostly confined to the cotyledons of the mature embryos, which resulted
in the accumulation of free fatty acids in dry seeds. The peroxisomal defect explains
the developmental phenotypes of the uox mutant, drawing a novel link
between uric acid and peroxisome function, which may be relevant beyond plants. 相似文献
995.
Gerhard Anders 《The journal of the Royal Anthropological Institute》2014,20(3):426-444
This article examines how social anthropologists' expertise was employed in the international war crimes trials heard at the Special Court for Sierra Leone. It tracks how the anthropologists challenged the prosecution experts by raising concerns about their methodology and advancing a fundamental critique of abstract legal categories. The discussion between the experts centred on two contested issues: the character of the armed groups and the phenomenon of forced marriages during the civil war in Sierra Leone. The analysis of the experts' testimonies shows that the anthropologists were engaged in an epistemological contest with the prosecution experts. The article aims at understanding why the anthropologists' arguments had less resonance with the judges than the reports submitted by the prosecution experts. Beyond the courtroom, it also speaks to the general debate about expertise and ways to study it. 相似文献
996.
Hedieh Shahpasandzadeh Blagovesta Popova Alexandra Kleinknecht Paul E. Fraser Tiago F. Outeiro Gerhard H. Braus 《The Journal of biological chemistry》2014,289(45):31224-31240
Parkinson disease is associated with the progressive loss of dopaminergic neurons from the substantia nigra. The pathological hallmark of the disease is the accumulation of intracytoplasmic inclusions known as Lewy bodies that consist mainly of post-translationally modified forms of α-synuclein. Whereas phosphorylation is one of the major modifications of α-synuclein in Lewy bodies, sumoylation has recently been described. The interplay between α-synuclein phosphorylation and sumoylation is poorly understood. Here, we examined the interplay between these modifications as well as their impact on cell growth and inclusion formation in yeast. We found that α-synuclein is sumoylated in vivo at the same sites in yeast as in human cells. Impaired sumoylation resulted in reduced yeast growth combined with an increased number of cells with inclusions, suggesting that this modification plays a protective role. In addition, inhibition of sumoylation prevented autophagy-mediated aggregate clearance. A defect in α-synuclein sumoylation could be suppressed by serine 129 phosphorylation by the human G protein-coupled receptor kinase 5 (GRK5) in yeast. Phosphorylation reduced foci formation, alleviated yeast growth inhibition, and partially rescued autophagic α-synuclein degradation along with the promotion of proteasomal degradation, resulting in aggregate clearance in the absence of a small ubiquitin-like modifier. These findings suggest a complex interplay between sumoylation and phosphorylation in α-synuclein aggregate clearance, which may open new horizons for the development of therapeutic strategies for Parkinson disease. 相似文献
997.
998.
Nina Weller Petra Clowes Gerhard Dobler Elmar Saathoff Inge Kroidl Nyanda Elias Ntinginya Leonard Maboko Thomas L?scher Michael Hoelscher Norbert Heinrich 《PLoS neglected tropical diseases》2014,8(7)
Background
To date, Alphavirus infections and their most prominent member, chikungunya fever, a viral disease which first became apparent in Tanzania in 1953, have been very little investigated in regions without epidemic occurrence. Few data exist on burden of disease and socio-economic and environmental covariates disposing to infection.Methods
A cross-sectional seroprevalence study was undertaken in 1,215 persons from Mbeya region, South-Western Tanzania, to determine the seroprevalence of anti-Alphavirus IgG antibodies, and to investigate associated risk factors.Results
18% of 1,215 samples were positive for Alphavirus IgG. Seropositivity was associated with participant age, low to intermediate elevation, flat terrain and with IgG positivity for Rift Valley fever, Flaviviridae, and rickettsiae of the spotted fever group. When comparing the geographical distribution of Alphavirus seropositivity to that of Rift Valley fever, it was obvious that Alphaviruses had spread more widely throughout the study area, while Rift Valley fever was concentrated along the shore of Lake Malawi.Conclusion
Alphavirus infections may contribute significantly to the febrile disease burden in the study area, and are associated with several arthropod-borne infections. Their spread seems only limited by factors affecting mosquitoes, and seems less restricted than that of Rift Valley fever. 相似文献999.
Jelena Kornej Borislav Dinov Andrew D. Blann Sascha Rolf Arash Arya Josephine Schmidl Daniela Husser Gerhard Hindricks Andreas Bollmann Gregory Y. H. Lip 《PloS one》2014,9(11)
Background
Catheter ablation (CA) of atrial fibrillation (AF) is associated with inflammatory response, endothelial damage and with increased risk of thrombosis. However, whether these processes differ in peripheral and cardiac circulation is unknown.Methods
Plasma markers (von Willebrand factor (vWf), soluble P-selectin (sPsel) and interleukin-6 (IL-6)) were measured by ELISA at three time points in 80 patients (62±10 years, 63% males, 41% paroxysmal AF) undergoing CA. These were at baseline – from femoral vein (FV) and left atrium (LA) before ablation; directly after ablation – from the pulmonary vein (PV), LA and FV; and 24 hours after procedure – from a cubital vein (CV).Results
The levels of vWF and IL6 – but not sP-sel – increased significantly 24h after procedure (p<0.001). Baseline vWF was significantly associated with persistent AF (Beta = .303, p = 0.006 and Beta = .300, p = 0.006 for peripheral and cardiac levels, respectively), while persistent AF (Beta = .250, p = 0.031) and LAA flow pattern (Beta = .386, p<0.001) remained associated with vWF in cardiac blood after ablation. Advanced age was significantly associated with IL6 levels at baseline and after ablation in peripheral and cardiac blood. There were no clinical, procedural or anti-coagulation characteristics associated with sP-sel levels in cardiac blood, while peripheral sP-sel levels were associated with hypertension before (Beta = −.307, p = 0.007) and with persistent AF after ablation (Beta = −.262, p = 0.020).Conclusions
vWF levels are higher in persistent AF and are associated with LAA rheological pattern after AF ablation. Increase of peripheral vWF and IL6 levels after procedure supports current AF ablation management with careful control of post-procedural anticoagulation to avoid ablation-related thromboembolism. 相似文献1000.
Sebastian Steibl Robert Sigl Sanja Blaha Sophia Drescher Gerhard Gebauer Elif Gürkal Frederic Hüftlein Anna Satzger Michael Schwarzer Dimitri Seidenath Jana Welfenbach Raphael S. Zinser Christian Laforsch 《Ecology and evolution》2021,11(19):13128
Ecosystems are interconnected by energy fluxes that provide resources for the inhabiting organisms along the transition zone. Especially where in situ resources are scarce, ecosystems can become highly dependent on external resources. The dependency on external input becomes less pronounced in systems with elevated in situ production, where only consumer species close to the site of external input remain subsidized, whereas species distant to the input site rely on the in situ production of the ecosystem. It is largely unclear though if this pattern is consistent over different consumer species and trophic levels in one ecosystem, and whether consumer species that occur both proximate to and at a distance from the input site differ in their dependency on external resource inputs between sites. Using stable isotope analysis, we investigated the dependency on external marine input for common ground‐associated consumer taxa on small tropical islands with high in situ production. We show that marine input is only relevant for strict beach‐dwelling taxa, while the terrestrial vegetation is the main carbon source for inland‐dwelling taxa. Consumer species that occurred both close (beach) and distant (inland) to the site of marine input showed similar proportions of marine input in their diets. This supports earlier findings that the relevance of external resources becomes limited to species close to the input site in systems with sufficient in situ production. However, it also indicates that the relevance of external input is also species‐dependent, as consumers occurring close and distant to the input site depended equally strong or weak on marine input. 相似文献