15 research outputs found
The origin of RXJ1856.5-3754 and RXJ0720.4-3125 -- updated using new parallax measurements
RXJ1856 and RXJ0720 are the only young isolated radio-quiet neutron stars
(NSs) for which trigonometric parallaxes were measured. Due to detection of
their thermal emission in X-rays they are important to study NS cooling and to
probe theoretical cooling models. Hence, a precise determination of their age
is essential. Recently, new parallax measurements of RXJ1856 and RXJ0720 were
obtained. Considering that NSs may originate from binary systems that got
disrupted due to an asymmetric supernova, we attempt to identify runaway stars
which may have been former companions to the NS progenitors. Such an
identification would strongly support a particular birth scenario with time and
place. We trace back each NS, runaway star and the centres of possible birth
associations to find close encounters. The kinematic age is then given by the
time since the encounter. We use Monte Carlo simulations to account for
observational uncertainties. Using the most recent parallax measurement of
8.16+/-0.80 mas for RXJ1856, we find that it originated in the U Sco
association 0.46+/-0.05 Myr ago. This is slightly larger than the value we
reported earlier (0.3 Myr). Our result is strongly supported by its current
radial velocity that we predict to be 6+19-20 km/s. This implies an inclination
angle of 88+/-6 deg consistent with the bow shock. No suitable runaway star was
found to be a potential former companion of RXJ1856. Making use of a recent
parallax measurement for RXJ0720 of 3.6+/-1.6 mas, we find that this NS was
possibly born in Tr 10 0.85+/-0.15 Myr ago. This is somewhat larger than the
one obtained using the old parallax value (0.5 Myr). We suggest the B0 runaway
supergiant HIP 43158 as a candidate for a former companion. Then, the current
distance of RXJ0720 to the Sun should be 286+27-23 pc, in agreement with recent
measurements. We then expect the radial velocity of RXJ0720 to be -76+34-17
km/s.Comment: accepted for publication in MNRAS additional supporting material can
be found at http://www.astro.uni-jena.de/~nina/supporting_info.pdf the
abstract has been adjusted to fit the length requirement (RXJ1856 =
RXJ1856.5-3754, RXJ0720 = RXJ0720.4-3125, U Sco = Upper Scorpius, Tr 10 =
Trumpler 10
Discovery of an OB Runaway Star Inside SNR S147
We present first results of a long term study: Searching for OB--type runaway
stars inside supernova remnants (SNRs). We identified spectral types and
measured radial velocities (RV) by optical spectroscopic observations and we
found an early type runaway star inside SNR S147. HD 37424 is a B0.5V type star
with a peculiar velocity of 748 km s. Tracing back the past
trajectories via Monte Carlo simulations, we found that HD 37424 was located at
the same position as the central compact object, PSR J0538+2817,
kyr ago. This position is only 4 arcmin away from the geometrical center
of the SNR. So, we suggest that HD 37424 was the pre--supernova binary
companion to the progenitor of the pulsar and the SNR. We found a distance of
1333 pc to the SNR. The zero age main sequence progenitor mass
should be greater than 13 . The age is kyr and the total
visual absorption towards the center is 1.280.06 mag. For different
progenitor masses, we calculated the pre--supernova binary parameters. The
Roche Lobe radii suggest that it was an interacting binary in the late stages
of the progenitor.Comment: Accepted to be published in MNRAS, 10 pages, 5 figure
Interprofessional collaboration in nursing homes (interprof): A grounded theory study of general practitioner experiences and strategies to perform nursing home visits
Background: Interprofessionalism, considered as collaboration between medical professionals, has gained prominence over recent decades and evidence for its impact has grown. The steadily increasing number of residents in nursing homes will challenge medical care and the interaction across professions, especially nurses and general practitioners (GPS). The nursing home visit, a key element of medical care, has been underrepresented in research. This study explores GP perspectives on interprofessional collaboration with a focus on their visits to nursing homes in order to understand their experiences and expectations. This research represents an aspect of the interprof study, which explores medical care needs as well as the perceived collaboration and communication by nursing home residents, their families, GPS and nurses. This paper focusses on GPS' views, investigating in particular their visits to nursing homes in order to understand their experiences. Methods: Open guideline-interviews covering interprofessional collaboration and the visit process were conducted with 30 GPS in three study centers and analyzed with grounded theory methodology. GPS were recruited via postal request and existing networks of the research partners. Results: Four different types of nursing home visits were found: visits on demand, periodical visits, nursing home rounds and ad-hoc-decision based visits. We identified the core category "productive performance" of home visits in nursing homes which stands for the balance of GPĆ individual efforts and rewards. GPS used different strategies to perform a productive home visit: preparing strategies, on-site strategies and investing strategies. Conclusion: We compiled a theory of GPS home visits in nursing homes in Germany. The findings will be useful for research, and scientific and management purposes to generate a deeper understanding of GP perspectives and thereby improve interprofessional collaboration to ensure a high quality of care
Interprofessional collaboration in nursing homes (interprof): A grounded theory study of general practitioner experiences and strategies to perform nursing home visits
Background: Interprofessionalism, considered as collaboration between medical professionals, has gained prominence over recent decades and evidence for its impact has grown. The steadily increasing number of residents in nursing homes will challenge medical care and the interaction across professions, especially nurses and general practitioners (GPS). The nursing home visit, a key element of medical care, has been underrepresented in research. This study explores GP perspectives on interprofessional collaboration with a focus on their visits to nursing homes in order to understand their experiences and expectations. This research represents an aspect of the interprof study, which explores medical care needs as well as the perceived collaboration and communication by nursing home residents, their families, GPS and nurses. This paper focusses on GPS' views, investigating in particular their visits to nursing homes in order to understand their experiences. Methods: Open guideline-interviews covering interprofessional collaboration and the visit process were conducted with 30 GPS in three study centers and analyzed with grounded theory methodology. GPS were recruited via postal request and existing networks of the research partners. Results: Four different types of nursing home visits were found: visits on demand, periodical visits, nursing home rounds and ad-hoc-decision based visits. We identified the core category "productive performance" of home visits in nursing homes which stands for the balance of GPĆ individual efforts and rewards. GPS used different strategies to perform a productive home visit: preparing strategies, on-site strategies and investing strategies. Conclusion: We compiled a theory of GPS home visits in nursing homes in Germany. The findings will be useful for research, and scientific and management purposes to generate a deeper understanding of GP perspectives and thereby improve interprofessional collaboration to ensure a high quality of care
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Effects of strategies to improve general practitioner-nurse collaboration and communication in regard to hospital admissions of nursing home residents (interprof ACT): study protocol for a cluster randomised controlled trial
Background: In Germany, up to 50% of nursing home residents are admitted to a hospital at least once a year. It is often unclear whether this is beneficial or even harmful. Successful interprofessional collaboration and communication involving general practitioners (GPs) and nurses may improve medical care of nursing home residents. In the previous interprof study, the six-component intervention package interprof ACT was developed to facilitate collaboration of GPs and nurses in nursing homes. The aim of this study is to evaluate the effectiveness of the interprof ACT intervention. Methods: This multicentre, cluster randomised controlled trial compares nursing homes receiving the interprof ACT intervention package for a duration of 12 months (e.g. comprising appointment of mutual contact persons, shared goal setting, standardised GPs' home visits) with a control group (care as usual). A total of 34 nursing homes are randomised, and overall 680 residents recruited. The intervention package is presented in a kick-off meeting to GPs, nurses, residents/relatives or their representatives. Nursing home nurses act as change agents to support local adaption and implementation of the intervention measures. Primary outcome is the cumulative incidence of hospitalisation within 12 months. Secondary outcomes include admissions to hospital, days admitted to hospital, use of other medical services, prevalence of potentially inappropriate medication and quality of life. Additionally, health economic and a mixed methods process evaluation will be performed. Discussion: This study investigates a complex intervention tailored to local needs of nursing homes. Outcomes reflect the healthcare and health of nursing home residents, as well as the feasibility of the intervention package and its impact on interprofessional communication and collaboration. Because of its systematic development and its flexible nature, interprof ACT is expected to be viable for large-scale implementation in routine care services regardless of local organisational conditions and resources available for medical care for nursing home residents on a regular basis. Recommendations will be made for an improved organisation of primary care for nursing home residents. In addition, the results may provide important knowledge and data for the development and evaluation of further strategies to improve outpatient care for elderly care-receivers
Additional file 1: of Interprofessional collaboration in nursing homes (interprof): development and piloting of measures to improve interprofessional collaboration and communication: a qualitative multicentre study
Interview guidelines study part 1. (PDF 192 kb
Implementation, mechanisms of change and contextual factors of a complex intervention to improve interprofessional collaboration and the quality of medical care for nursing home residents: study protocol of the process evaluation of the interprof ACT intervention package
Background: To improve interprofessional collaboration between registered nurses (RNs) and general practitioners (GPs) for nursing home residents (NHRs), the interprof ACT intervention package was developed. This complex intervention includes six components (e.g., shared goal setting, standardized procedures for GPsâ nursing home visits) that can be locally adapted. The clusterârandomized interprof ACT trial evaluates the effects of this intervention on the cumulative incidence of hospital admissions (primary outcome) and secondary outcomes (e.g., length of hospital stays, utilization of emergency care services, and quality of life) within 12 months. It also includes a process evaluation which is subject of this protocol. The objectives of this evaluation are to assess the implementation of the interprof ACT intervention package and downstream effects on nurseâphysician collaboration as well as preconditions and prospects for successive implementation into routine care.
Methods: This study uses a mixed methods triangulation design involving all 34 participating nursing homes (clusters). The quantitative part comprises paperâbased surveys among RNs, GPs, NHRs, and nursing home directors at baseline and 12 months. In the intervention group (17 clusters), data on the implementation of preplanned implementation strategies (training and supervision of nominated IPAVs, interprofessional kickâoff meetings) and local implementation activities will be recorded. Major outcome domains are the dose, reach and fidelity of the implementation of the intervention package, changes in interprofessional collaboration, and contextual factors. The qualitative part will be conducted in a subsample of 8 nursing homes (4 per study group) and includes repeated nonâparticipating observations and semistructured interviews on the interaction between involved health professionals and their work processes. Quantitative and qualitative data will be descriptively analyzed and then triangulated by means of joint displays and mixed methods informed regression models.
Discussion: By integrating a variety of qualitative and quantitative data sources, this process evaluation will allow comprehensive assessment of the implementation of the interprof ACT intervention package, the changes induced in interprofessional collaboration, and the influence of contextual factors. These data will reveal expected and unexpected changes in the procedures of interprofessional care delivery and thus facilitate accurate conclusions for the further design of routine care services for NHRs