36 resultados para DONOR ATOM SET
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Since the Moon is not shielded by a global magnetic field or by an atmosphere, solar wind plasma impinges onto the lunar surface almost unhindered. Until recently, it was assumed that almost all of the impinging solar wind ions are absorbed by the surface. However, recent Interstellar Boundary Explorer, Chandrayaan-1, and Kaguya observations showed that the interaction process between the solar wind ions and the lunar surface is more complex than previously assumed. In contrast to previous assumptions, a large fraction of the impinging solar wind ions is backscattered as energetic neutral atoms. Using the complete Chandrayaan-1 Energetic Neutral Analyzer data set, we compute a global solar wind reflection ratio of 0.16 ± 0.05 from the lunar surface. Since these backscattered neutral particles are not affected by any electric or magnetic fields, each particle's point of origin on the lunar surface can be determined in a straight-forward manner allowing us to create energetic neutral atom maps of the lunar surface. The energetic neutral atom measurements recorded by the Chandrayaan-1 Energetic Neutral Analyzer cover ˜89% of the lunar surface, whereby the lunar farside is almost completely covered. We analyzed all available energetic neutral atom measurements recorded by the Chandrayaan-1 Energetic Neutral Analyzer to create the first global energetic neutral hydrogen maps of the lunar surface.
Resumo:
In fetal alloimmune thrombocytopenia (FAIT), transplacental maternal antibodies cause destruction of fetal platelets. FAIT is similar to fetal Rhesus haemolytic disease, but half of the affected fetuses are born to primiparous women. In 10-20% of cases, prenatal and perinatal intracranial haemorrhages are reported. Different therapeutic approaches have been described, including maternally administered high-dose intravenous immunoglobulin (high dose IVIG) without or with steroids or intrauterine transfusion (IUT) of compatible platelets. For the latter, the use of plasma-free maternal and donor platelets has been described, but a comparison of these two sources of platelets has not been reported.
Resumo:
HIV virulence, i.e. the time of progression to AIDS, varies greatly among patients. As for other rapidly evolving pathogens of humans, it is difficult to know if this variance is controlled by the genotype of the host or that of the virus because the transmission chain is usually unknown. We apply the phylogenetic comparative approach (PCA) to estimate the heritability of a trait from one infection to the next, which indicates the control of the virus genotype over this trait. The idea is to use viral RNA sequences obtained from patients infected by HIV-1 subtype B to build a phylogeny, which approximately reflects the transmission chain. Heritability is measured statistically as the propensity for patients close in the phylogeny to exhibit similar infection trait values. The approach reveals that up to half of the variance in set-point viral load, a trait associated with virulence, can be heritable. Our estimate is significant and robust to noise in the phylogeny. We also check for the consistency of our approach by showing that a trait related to drug resistance is almost entirely heritable. Finally, we show the importance of taking into account the transmission chain when estimating correlations between infection traits. The fact that HIV virulence is, at least partially, heritable from one infection to the next has clinical and epidemiological implications. The difference between earlier studies and ours comes from the quality of our dataset and from the power of the PCA, which can be applied to large datasets and accounts for within-host evolution. The PCA opens new perspectives for approaches linking clinical data and evolutionary biology because it can be extended to study other traits or other infectious diseases.
Resumo:
This paper presents a kernel density correlation based nonrigid point set matching method and shows its application in statistical model based 2D/3D reconstruction of a scaled, patient-specific model from an un-calibrated x-ray radiograph. In this method, both the reference point set and the floating point set are first represented using kernel density estimates. A correlation measure between these two kernel density estimates is then optimized to find a displacement field such that the floating point set is moved to the reference point set. Regularizations based on the overall deformation energy and the motion smoothness energy are used to constraint the displacement field for a robust point set matching. Incorporating this non-rigid point set matching method into a statistical model based 2D/3D reconstruction framework, we can reconstruct a scaled, patient-specific model from noisy edge points that are extracted directly from the x-ray radiograph by an edge detector. Our experiment conducted on datasets of two patients and six cadavers demonstrates a mean reconstruction error of 1.9 mm
Donor effect on cortical perfusion intensity in renal allograft recipients: a paired kidney analysis
Resumo:
The contributions of donor- and recipient-related factors to renal allograft hemodynamics are difficult to dissect due to methodological reasons. We analyzed 28 pairs of kidneys (each pair from the same donor) transplanted to 56 different recipients in order to define the contributions of the donor and the recipient to allograft hemodynamics.
Resumo:
The in vivo autologous serum skin test (ASST) is the diagnostic gold standard to detect autoantibodies against FcεRI or IgE itself, as well as other autoreactive serum components, in patients with chronic spontaneous urticaria (CU). Coincubation of patient sera with donor basophils and measuring their degranulation in vitro could be a safe alternative but has shown inconsistent results.
Resumo:
SUMMARY: BACKGROUND: Recruitment of platelets (PLT) during donor PLT apheresis may facilitate the harvest of multiple units within a single donation. METHODS: We compared two PLT apheresis procedures (Amicus and Trima Accel) in a prospective, randomized, paired cross-over study in 60 donors. The 120 donations were compared for depletion of circulating PLT in the donors, PLT yields and PLT recruitment. A recruitment was defined as ratio of total PLT yield and donor PLT depletion > 1. RESULTS: Despite comparable differences of pre- and post-apheresis PLT counts (87 × 10(9)/l in Trima Accel vs. 92 × 10(9)/l in Amicus, p = 0.383), PLT yields were higher with Trima Accel (7.48 × 10(11) vs. 6.06 × 10(11), p < 0.001), corresponding to a higher PLT recruitment (1.90 vs. 1.42, p < 0.001). We observed a different increase of WBC counts after aphereses, which was more pronounced with Trima Accel than with Amicus (1.30 × 10(9)/l vs. 0.46 × 10(9)/l, p < 0.001). CONCLUSION: Both procedures induced PLT recruitment. This was higher in Trima Accel, contributing to a higher yield in spite of a comparable depletion of circulating PLT in the donors. This recruitment facilitates the harvest of multiple units within a single donation and seems to be influenced by the procedure utilized. The different increases of circulating donor white blood cells after donation need further investigation.