1,526 research outputs found
Ăber die Moderation schenller Neutronen in PolyĂ€theylen und ihre Anwendung in der Neotronendosimetrie. EUR 4540. = The moderation of fast neutrons in polyethylene and their use in neutron dosimetry. EUR 4540.
Staging for distant metastases in operable breast cancer: a suggested expansion of the ESMO guideline recommendation for staging imaging of node-negative, hormonal receptor-negative disease
We evaluated the impact of staging procedures to detect asymptomatic distant metastases (DM) in the management of women with operable invasive breast cancer (BC, entire cohort: n = 866). Out of 472 patients with lymph node (LN)-negative disease (pN0), DM were found in four cases (detection rate: 0.8%). All four patients presented with established risk factors: hormone receptor (HR)-negative status, HER2-positive status, n = 3; âtriple-negative' disease, n = 1. Considering the subgroup of LN-negative patients whose tumors showed the risk factor ânegative HR status' (n = 66), the detection rate of DM was 6%. The detection rates of DM in higher pN categories were as follows: pN1:1.7%; pN2:9.5%; pN3:13.5%. We generally support the international guidelines, including those published by the European Society for Medical Oncology (ESMO) which emphasize that patients with early-stage BC do not profit from radiological staging for the detection of DM and recommend refraining from this. However, we would expand these guidelines and propose that screening should be carried out in node-negative patients whose tumors show established tumor-related risk factors (e.g. HR-negative and HER2-positive status), since in this particular subcohort, the detection rate of DM is with 6% similarly high as that of patients with four to nine positive LN
The optical system of the H.E.S.S. imaging atmospheric Cherenkov telescopes, Part II: mirror alignment and point spread function
Mirror facets of the H.E.S.S. imaging atmospheric Cherenkov telescopes are
aligned using stars imaged onto the closed lid of the PMT camera, viewed by a
CCD camera. The alignment procedure works reliably and includes the automatic
analysis of CCD images and control of the facet alignment actuators. On-axis,
80% of the reflected light is contained in a circle of less than 1 mrad
diameter. The spot widens with increasing angle to the telescope axis. In
accordance with simulations, the spot size has roughly doubled at an angle of
1.4 degr. from the axis. The expected variation of spot size with elevation due
to deformations of the support structure is visible, but is completely
non-critical over the usual working range. Overall, the optical quality of the
telescope exceeds the specifications.Comment: 23 pages, 13 figure
Antibody-based immunotherapy for ovarian cancer: where are we at?
Cytoreductive surgery and chemotherapy continue to be the mainstay of ovarian cancer treatment. However, as mortality from advanced ovarian cancer remains very high, novel therapies are required to be integrated into existing treatment regimens. Immunotherapy represents an alternative and rational therapeutic approach for ovarian cancer based on a body of evidence supporting a protective role of the immune system against these cancers, and on the clinical success of immunotherapy in other malignancies. Whether or not immunotherapy will have a role in the future management of ovarian cancer is too early to tell, but research in this field is active. This review will discuss recent clinical developments of selected immunotherapies for ovarian cancer which fulfil the following criteria: (i) they are antibody-based, (ii) target a distinct immunological pathway, and (iii) have reached the clinical trial stage. Specifically, the focus is on Catumaxomab (anti-EpCAM Ă anti-CD3), Abagovomab, Oregovomab (anti-CA125), Daclizumab (anti-CD25), Ipilimumab (anti-CTLA-4), and MXD-1105 (anti-PD-L1). Catumaxomab has reached phase III clinical trials and exhibits promise with reports, showing that it can cause a significant and sustained reduction in ascites. Phase I-III clinical trials continue to be conducted on the other antibodies, some of which have had encouraging reports. We will also provide our perspective on the future of immunotherapy for ovarian cancer, and how it may be best employed in treatment regimen
The metastatic potential of seminomatous germ cell tumours is associated with a specific microRNA pattern
Background
Seminomatous germ cell tumours (SGCT) are the most frequent malignancy in young men. Reliable prognostic biomarkers for the prediction of metastasis at diagnosis and the risk of relapse in clinical stage I (CSI) are lacking. Adjuvant therapies carry a risk of overtreatment, whereas salvage therapies have a risk of high toxicities. Thus, the identification of reliable prognostic biomarkers is highly desirable to identify patients who will benefit from early adjuvant treatment. MicroRNAs (miRNAs) regulate tumour development and progression, and their potential as biomarkers has already been proven in a variety of malignancies.
Objectives
The aim of our study was to define a specific miRNA expression pattern that discriminates metastatic from nonâmetastatic primary SGCT.
Materials and methods
Total RNA was isolated from 24 formalinâfixed paraffinâembedded (FFPE) primary SGCT tumours (10 nonâmetastatic, five metachronously and nine synchronously metastatic) and from 10 normal testicular tissue samples. Microarray analysis was performed for global miRNA expression profiling. The results were validated by quantitative realâtime polymerase chain reaction (qRTâPCR). Statistical analysis was performed using SPSS.
Results
Microarray analyses revealed a specific miRNA pattern that distinguishes metastatic from nonâmetastatic SGCT. Sixtyâthree miRNAs were differentially expressed in metastatic compared to nonâmetastatic tumours (P < .01). Microarray results were confirmed by qRTâPCR for three out of five selected miRNAs (miRâ29câ5p, miRâ506â3p and miRâ371aâ5p; P < .05). All five miRNAs (miRâ29câ5p, miRâ506â3p, miRâ1307â5p, miRâ371aâ5p and miRâ371aâ3p) showed differential expression between tumour and normal tissues (P < .05).
Conclusion
Metastatic primary SGCTs are characterized by a specific miRNA expression pattern. Therefore, specific miRNAs could represent a new tool to predict the metastatic potential in SGCT patients
An unidentified TeV source in the vicinity of Cygnus OB2
Deep observation (âŒ113 hrs) of the Cygnus region at TeV energies using the HEGRA stereoscopic system of air Äerenkov telescopes has serendipitously revealed a signal positionally inside the core of the OB association Cygnus OB2, at the edge of the 95% error circle of the EGRET source 3EG J2033+4118, and âŒ0.5° north of Cyg X-3. The source centre of gravity is RA αJ2000: 20hr32m07s± 9.2stats±2.2syss, Dec ÎŽJ2000: +41°30âČ30âł2.0stat±0.4âČsys. The source is steady, has a post-trial significance of +4.6Ï, indication for extension with radius 5.6âČ at the âŒ3Ï level, and has a differential power-law flux with hard photon index of - 1.9 ± 0.3stat ± 0.3sys. The integral flux above 1 TeV amounts âŒ3% that of the Crab. No counterpart for the TeV source at other wavelengths is presently identified, and its extension would disfavour an exclusive pulsar or AGN origin. If associated with Cygnus OB2, this dense concentration of young, massive stars provides an environment conducive to multi-TeV particle acceleration and likely subsequent interaction with a nearby gas cloud. Alternatively, one could envisage Îł-ray production via a jet-driven termination shock.F. A. Aharonian, ... G. P. Rowell, ... [et al
Single-boson exchange functional renormalization group application to the two-dimensional Hubbard model at weak coupling
We illustrate the algorithmic advantages of the recently introduced
single-boson exchange (SBE) formulation for the one-loop functional
renormalization group (fRG), by applying it to the two-dimensional Hubbard
model on a square lattice. We present a detailed analysis of the fermion-boson
Yukawa couplings and of the corresponding physical susceptibilities by studying
their evolution with temperature and interaction strength, both at half filling
and finite doping. The comparison with the conventional fermionic fRG
decomposition shows that the rest functions of the SBE algorithm, which
describe correlation effects beyond the SBE processes, play a negligible role
in the weak-coupling regime above the pseudo-critical temperature, in contrast
to the rest functions of the conventional fRG. Remarkably, they remain finite
also at the pseudo-critical transition, whereas the corresponding rest
functions of the conventional fRG implementation diverge. As a result, the SBE
formulation of the fRG flow allows for a substantial reduction of the numerical
effort in the treatment of the two-particle vertex function, paving a promising
route for future multiboson and multiloop extensions
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