512 research outputs found
Huge Transverse Magnetization in the Field-Induced Phase of the Antiferromagnetic Molecular Wheel CsFe8
The 1H-NMR spectrum and nuclear relaxation rate 1/T_1 in the
antiferromagnetic wheel CsFe8 were measured to characterize the previously
observed magnetic field-induced low-temperature phase around the level crossing
at 8 T. The data show that the phase is characterized by a huge staggered
transverse polarization of the electronic Fe spins, and the opening of a gap,
providing microscopic evidence for the interpretation of the phase as a
field-induced magneto-elastic instability.Comment: 5 pages, 4 figures, REVTEX4, to appear in PR
The effect of neoadjuvant therapy on PD-L1 expression and CD8+lymphocyte density in non-small cell lung cancer.
PD-L1 expression is the routine clinical biomarker for the selection of patients to receive immunotherapy in non-small cell lung cancer (NSCLC). However, the application and best timing of immunotherapy in the resectable setting is still under investigation. We aimed to study the effect of chemotherapy on PD-L1 expression and tumor infiltrating lymphocytes (TILs), which is to date still poorly understood. Our retrospective, single-centre neoadjuvant cohort comprised 96 consecutive patients with NSCLC resected 2000-2016 after neoadjuvant therapy, including paired diagnostic chemo-naïve specimens in 53 cases. A biologically matched surgical cohort of 114 primary resected cases was included. PD-L1 expression, CD8 + TILs density and tertiary lymphoid structures were assessed on whole slides and correlated with clinico-pathological characteristics and survival. Seven/53 and 12/53 cases had lower respectively higher PD-L1 expressions after neoadjuvant therapy. Most cases (n = 34) showed no changes in PD-L1 expression, the majority of these harboring PD-L1 < 1% in both samples (21/34 [61.8%]). Although CD8 + TILs density was significantly higher after chemotherapy (p = 0.031) in resections compared to diagnostic biopsies, this might be due to sampling and statistical bias. No difference in PD-L1 expression or CD8 + TILs density was detected when comparing the neoadjuvant and surgical cohort. In univariable analyses, higher CD8 + TILs density, higher numbers of tertiary lymphoid structures but not PD-L1 expression were significantly associated with longer survival. Increased PD-L1 expression after neoadjuvant chemotherapy was not significantly associated with shorter 5-year survival, but the number of cases was very low. In multivariable analysis, only pT category and age remained independent prognostic factors. In summary, PD-L1 expression was mostly unchanged after neoadjuvant chemotherapy compared to diagnostic biopsies. The sample size of cases with changed PD-L1 expression was too small to draw conclusions on any prognostic value
Protective T Cell–Independent Antiviral Antibody Responses Are Dependent on Complement
Complement is part of the innate immune system and one of the first lines of host defense against infections. Its importance was evaluated in this study in virus infections in mice deficient either in soluble complement factors (C3−/−, C4−/−) or in the complement signaling complex (complement receptor [CR]2−/−, CD19−/−). The induction of the initial T cell–independent neutralizing immunoglobulin (Ig)M antibody response to vesicular stomatitis virus (VSV), poliomyelitis virus, and recombinant vaccinia virus depended on efficient antigen trapping by CR3 and -4–expressing macrophages of the splenic marginal zone. Neutralizing IgM and IgG antibody responses were largely independent of CR2-mediated stimulation of B cells when mice were infected with live virus. In contrast, immunizations with nonreplicating antigens revealed an important role of B cell stimulation via CR2 in the switch to IgG. The complement cascade was activated after infection with VSV via the classical pathway, and active complement cleavage products augmented the effector function of neutralizing IgM and IgG antibodies to VSV by a factor of 10–100. Absence of the early neutralizing antibody responses, together with the reduced efficiency of neutralizing IgM in C3−/− mice, led to a drastically enhanced susceptibility to disease after infection with VSV
A prognostic score for non-small cell lung cancer resected after neoadjuvant therapy in comparison with the tumor-node-metastases classification and major pathological response.
Studies validating the prognostic accuracy of the tumor-node-metastases (TNM) classification in patients with lung cancer treated by neoadjuvant therapy are scarce. Tumor regression, particularly major pathological response (MPR), is an acknowledged prognostic factor in this setting. We aimed to validate a novel combined prognostic score. This retrospective single-center study was conducted on 117 consecutive patients with non-small cell lung cancer resected after neoadjuvant treatment at a Swiss University Cancer Center between 2000 and 2016. All cases were clinicopathologically re-evaluated. We assessed the prognostic performance of a novel prognostic score (PRSC) combining T-category, lymph node status, and MPR, in comparison with the eighth edition of the TNM classification (TNM8), the size adapted TNM8 as proposed by the International Association for the Study of Lung Cancer (IASLC) and MPR alone. The isolated ypT-category and the combined TNM8 stages accurately differentiated overall survival (OS, stage p = 0.004) and disease-free survival (DFS, stage p = 0.018). Tumor regression had a prognostic impact. Optimal cut-offs for MPR emerged as 65% for adenocarcinoma and 10% for non-adenocarcinoma and were statistically significant for survival (OS p = 0.006, DFS p < 0.001). The PRSC differentiated between three prognostic groups (OS and DFS p < 0.001), and was superior compared to the stratification using MPR alone or the TNM8 systems, visualized by lower Akaike (AIC) and Bayesian information criterion (BIC) values. In the multivariate analyses, stage III tumors (HR 4.956, p = 0.003), tumors without MPR (HR 2.432, p = 0.015), and PRSC high-risk tumors (HR 5.692, p < 0.001) had significantly increased risks of occurring death. In conclusion, we support 65% as the optimal cut-off for MPR in adenocarcinomas. TNM8 and MPR were comparable regarding their prognostic significance. The novel prognostic score performed distinctly better regarding OS and DFS
Near and mid-IR sub-arcsecond structure of the dusty symbiotic star R Aqr
The results of a high-resolution interferometric campaign targeting the
symbiotic long-period variable (LPV) R~Aqr are reported. With both
near-infrared measurements on baselines out to 10m and mid-infrared data
extending to 32m, we have been able to measure the characteristic sizes of
regions from the photosphere of the LPV and its extended molecular atmosphere,
out to the cooler circumstellar dust shell. The near-infrared data were taken
using aperture masking interferometry on the Keck-I telescope and show R~Aqr to
be partially resolved for wavelengths out to 2.2 microns but with a marked
enlargement, possibly due to molecular opacity, at 3.1 microns. Mid-infrared
interferometric measurements were obtained with the U.C. Berkeley Infrared
Spatial Interferometer (ISI) operating at 11.15 microns from 1992 to 1999.
Although this dataset is somewhat heterogeneous with incomplete coverage of the
Fourier plane and sampling of the pulsation cycle, clear changes in the
mid-infrared brightness distribution were observed, both as a function of
position angle on the sky and as a function of pulsation phase. Spherically
symmetric radiative transfer calculations of uniform-outflow dust shell models
produce brightness distributions and spectra which partially explain the data,
however limitations to this approximation are noted. Evidence for significant
deviation from circular symmetry was found in the mid-infrared and more
tentatively at 3.08 microns in the near-infrared, however no clear detection of
binarity or of non-LPV elements in the symbiotic system is reported.Comment: Accepted to Astrophysical Journal. To appear in volume 534. 14 pages;
3 postscript figure
TREM-1 links dyslipidemia to inflammation and lipid deposition in atherosclerosis.
Triggering receptor expressed on myeloid cells-1 (TREM-1) is a potent amplifier of pro-inflammatory innate immune responses, but its significance in non-infectious diseases remains unclear. Here, we demonstrate that TREM-1 promotes cardiovascular disease by exacerbating atherosclerosis. TREM-1 is expressed in advanced human atheromas and is highly upregulated under dyslipidemic conditions on circulating and on lesion-infiltrating myeloid cells in the Apoe(-/-) mouse model. TREM-1 strongly contributes to high-fat, high-cholesterol diet (HFCD)-induced monocytosis and synergizes with HFCD serum-derived factors to promote pro-inflammatory cytokine responses and foam cell formation of human monocyte/macrophages. Trem1(-/-)Apoe(-/-) mice exhibit substantially attenuated diet-induced atherogenesis. In particular, our results identify skewed monocyte differentiation and enhanced lipid accumulation as novel mechanisms through which TREM-1 can promote atherosclerosis. Collectively, our findings illustrate that dyslipidemia induces TREM-1 surface expression on myeloid cells and subsequently synergizes with TREM-1 to enhance monopoiesis, pro-atherogenic cytokine production and foam cell formation
New Observations and Analysis of the Bright Semi-Detached Eclipsing Binary mu1 Sco
Using new and published photometric observations of mu1 Sco (HR 6247),
spanning 70 years, a period of 1.4462700(5) days was determined. It was found
that the epoch of primary minimum suggested by Shobbrook at HJD 2449534.178
requires an adjustment to HJD 2449534.17700(9) to align all the available
photometric datasets. Using the resulting combined-data light-curve, radial
velocities derived from IUE data and the modelling software PHOEBE, a new
system solution for this binary was obtained. It appears that the secondary is
close to, or just filling, its Roche-lobe.Comment: 4 figures, 6 tables, 9 pages, uses mn2e.sty, to be published in MNRA
1318 New Variable Stars in a 0.25 Square Degree Region of the Galactic Plane
We have conducted a deep photometric survey of a 0.5 deg x 0.5 deg area of
the Galactic Plane using the WFI instrument on the 2.2-m ESO telescope on La
Silla, Chile. The dataset comprises a total of 267 R-band images, 204 from a 16
day observation run in 2005, supplemented by 63 images from a six week period
in 2002. Our reduction employed the new numerical kernel difference image
analysis method as implemented in the PYSIS3 code and resulted in more than
500,000 lightcurves of stars down to a magnitude limit of R ~ 24.5. A search
for variable stars resulted in the detection of 1318 variables of different
types. 1011 of these are eclipsing or contact binary stars. A number of the
contact binaries have low mass-ratios and several of the detached binaries
appear to have low-mass components. Three candidate contact binaries have
periods at the known cut off including two with periods lower than any
previously published. Also identified are 3 possible pre-main sequence detached
eclipsing binaries.Comment: 54 pages, 17 figures, 11 tables, accepted by A&A. Photometry will be
available through CD
Kinematic parameters and membership probabilities of open clusters in the Bordeaux PM2000 catalogue
We derive lists of proper-motions and kinematic membership probabilities for
49 open clusters and possible open clusters in the zone of the Bordeaux PM2000
proper motion catalogue (). We test
different parametrisations of the proper motion and position distribution
functions and select the most successful one. In the light of those results, we
analyse some objects individually. The segregation between cluster and field
member stars, and the assignment of membership probabilities, is accomplished
by applying a new and fully automated method based on both parametrisations of
the proper motion and position distribution functions, and genetic algorithm
optimization heuristics associated with a derivative-based hill climbing
algorithm for the likelihood optimization. We present a catalogue comprising
kinematic parameters and associated membership probability lists for 49 open
clusters and possible open clusters in the Bordeaux PM2000 catalogue region. We
note that this is the first determination of proper motions for five open
clusters. We confirm the non-existence of two kinematic populations in the
region of 15 previously suspected non-existent objects.Comment: 14 pages, 6 figures, 4 tables. Accepted for publication in Astronomy
& Astrophysic
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