184 research outputs found
HLA class II antibodies at the time of kidney transplantation and cardiovascular outcome : a retrospective cohort study
Background.
The negative role of HLA class II donor-specific antibody on graft outcome is well recognized. However, the potentially negative cardiovascular effects of preformed HLA class II antibodies and donor HLA in kidney transplant recipients (KTRs) remain unestablished.
Methods.
We conducted a single-center, retrospective cohort study including 1115 KTRs (2003–2016) with up to 4449 person-years of follow-up after transplantation and a median follow-up time of 5.1 years (interquartile range, 2.7–7.6). We evaluated the unadjusted and multivariable-adjusted association between pretransplant HLA class I and II antibodies, as well as HLA-DR1 donor/recipient genotype and the primary (major adverse cardiac and cerebrovascular event [MACCE] or all-cause mortality) and secondary (MACCE or cardiovascular mortality) outcome.
Results.
In a multivariate Cox proportional hazard model, HLA class II antibodies before transplantation were associated with increased adjusted hazard ratio (aHR) for MACCE or all-cause mortality (aHR, 1.71 [1.13–2.60]; P = 0.012) even after adjustment for time-varying covariate graft loss (aHR, 1.68 [1.08–2.62]; P = 0.022) and biopsy-proven acute rejection (aHR, 1.71 [1.13–2.60]; P = 0.012). HLA class II antibodies were also associated with increased aHR for the secondary outcome, MACCE, or cardiovascular mortality (aHR, 1.92 [1.12–3.30]; P = 0.018). We investigated the effect of donor and recipient HLA-DR1 on these outcome parameters and demonstrated that KTRs with HLA-DR1 positive donors had an increased aHR for MACCE with all-cause (aHR, 1.45 [1.09–1.94]; P = 0.012) and cardiovascular mortality (aHR, 1.49 [1.00–2.22]; P = 0.05).
Conclusions.
Prior sensitization against HLA class II antigens is associated with unfavorable long-term cardiovascular outcome in KTRs independent of graft loss or rejection. Recipients of an HLA-DR1 donor also have an impaired cardiovascular outcome
Recommendations for anesthesia and perioperative management in patients with Ehlers-Danlos syndrome(s)
Ehlers-Danlos syndrome (EDS, ORPHA98249) comprises a group of clinically and genetically heterogeneous heritable connective tissue disorders, chiefly characterized by joint hypermobility and instability, skin texture anomalies, and vascular and soft tissue fragility. As many tissues can be involved, the underlying molecular defect can manifest itself in many organs and with varying degrees of severity, with widespread implications for anesthesia and perioperative management. This review focuses on issues relevant for anesthesia for elective and emergency surgery in EDS. We searched the literature for papers related to all EDS variants; at the moment most of the published data deals with the vascular subtype and, to a lesser extent, classic and hypermobility EDS. Knowledge is fragmented and consists mostly of case reports, small case series and expert opinion. Because EDS patients commonly require surgery, we have summarized some recommendations for general, obstetrical and regional anesthesia, as well as for hemostatic therapy
3D simulations of AGB stellar winds -- II. Ray-tracer implementation and impact of radiation on the outflow morphology
Stars with an initial mass below ~ 8 Msun evolve through the asymptotic giant
branch (AGB) phase, during which they develop strong stellar winds. Recent
observations have revealed significant morphological complexities in their
outflows, most likely caused by a companion. We study the impact of the
radiation force on such companion-perturbed AGB outflows. We present the
implementation of a ray tracer for radiative transfer in smoothed particle
hydrodynamics (SPH) and compared four different descriptions of radiative
transfer: the free-wind, the geometrical, the Lucy, and the attenuation
approximation. For both low and high mass-loss rates, the velocity profile of
the outflow is modified when going from the free-wind to the geometrical
approximation, also resulting in a different morphology. In the case of a low
mass-loss rate, the effect of the Lucy and attenuation approximation is
negligible due to the low densities but morphological differences appear in the
high mass-loss rate regime. By comparing the radiative equilibrium temperature
and radiation force to full 3D radiative transfer, we show that the Lucy
approximation works best. Although, close to the companion, artificial heating
occurs and it fails to simulate the shadow cast by the companion. The
attenuation approximation produces a lower equilibrium temperature and weaker
radiation force, but it produces the shadow cast by the companion. From the
predictions of the 3D radiative transfer, we also conclude that a radially
directed radiation force is a reasonable assumption. The radiation force thus
plays a critical role in dust-driven AGB winds, impacting the velocity profile
and morphological structures. For low mass-loss rates, the geometrical
approximation suffices, while high mass-loss rates require a more rigorous
method, where the Lucy approximation provides the most accurate results
although not accounting for all effects
Recent Results of Solid-State Spectroscopy
Solid state spectroscopy continues to be an important source of information
on the mineralogical composition and physical properties of dust grains both in
space and on planetary surfaces. With only a few exceptions, artificially
produced or natural terrestrial analog materials, rather than 'real' cosmic
dust grains, are the subject of solid state astrophysics. The Jena laboratory
has provided a large number of data sets characterizing the UV, optical and
infrared properties of such cosmic dust analogs. The present paper highlights
recent developments and results achieved in this context, focussing on
'non-standard conditions' such as very low temperatures, very high temperatures
and very long wavelengths.Comment: 15 pages, 10 figures. Contribution to an IAU Conference "The
Molecular Universe" held in Toledo in June 201
Haemoptysis as the first presentation of COVID-19 : a case report
Background Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing pandemic that profoundly challenges healthcare systems all over the world. Fever, cough and fatigue are the most commonly reported clinical symptoms. Case presentation A 58-year-old man presented at the emergency department with acute onset haemoptysis. On the fifth day after admission, he developed massive haemoptysis. Computed tomography (CT) angiography of the chest revealed alveolar haemorrhage, more prominent in the left lung. Flexible bronchoscopy confirmed bleeding from the left upper lobe, confirmed by a bronchial arteriography, which was successfully embolized. Nasopharyngeal swabs (NPS) tested for SARS-CoV-2 using real-time polymerase chain reaction (RT-PCR) repeatedly returned negative. Surprisingly, SARS-CoV-2 was eventually detected in bronchoalveolar lavage (BAL) fluid. Conclusions Life-threatening haemoptysis is an unusual presentation of COVID-19, reflecting alveolar bleeding as a rare but possible complication. This case emphasises the added value of bronchoscopy with BAL in the diagnostic work-up in case of high clinical suspicion and negative serial NPS in patients presenting with severe symptoms
Five-Year Survival After Endosonography vs Mediastinoscopy for Mediastinal Nodal Staging of Lung Cancer.
Lung cancer accounts for the highest cancer-related mortality rate worldwide.1 Accurate mediastinal nodal staging is crucial in the management of non–small cell lung cancer (NSCLC) because it directs therapy and has prognostic value.2,
Effects of Landscape Structure on Movement Patterns of the Flightless Bush Cricket Pholidoptera griseoaptera
Because the viability of a population may depend on whether individuals can disperse, it is important for conservation planning to understand how landscape structure affects movement behavior. Some species occur in a wide range of landscapes differing greatly in structure, and the question arises of whether these species are particularly versatile in their dispersal or whether they are composed of genetically distinct populations adapted to contrasting landscapes. We performed a capture-mark-resight experiment to study movement patterns of the flightless bush cricket Pholidoptera griseoaptera (De Geer 1773) in two contrasting agricultural landscapes in France and Switzerland. The mean daily movement of P. griseoaptera was significantly higher in the landscape with patchily distributed habitat (Switzerland) than in the landscape with greater habitat connectivity (France). Net displacement rate did not differ between the two landscapes, which we attributed to the presence of more linear elements in the connected landscape, resulting in a more directed pattern of movement by P. griseoaptera. Significant differences in the movement patterns between landscapes with contrasting structure suggest important effects of landscape structure on movement and dispersal success. The possibility of varying dispersal ability within the same species needs to be studied in more detail because this may provide important information for sustainable landscape planning aimed at maintaining viable metapopulations, especially in formerly well-connected landscape
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