100 research outputs found
Fecundity limits in Frangula alnus (Rhamnaceae) relict populations at the species' southern range margin
The geographic range of many temperate plant species is constrained by climate, but it remains little known how climate affects population performance at low-latitude range margins. This study investigated the reproduction of the Eurasian tree Frangula alnus in relict populations near its southwestern range limit in southern Spain. The aim was to identify the principal stages and causes of ovule loss experienced by these marginal populations. More than 6,800 flowers were monitored over 2 years, insect observations and different experiments were carried out to assess levels of pollen and resource limitation, as well as the influence of flowering phenology on seed production. Most ovule losses occurred during flower anthesis and were due to strong cross-pollen limitation. Fruit set was affected by tree size, light regime and flowering phenology, probably through their effects on pollinator behaviour. Fruit set was almost zero throughout the first half of the flowering season. Then it increased paralleling changes in pollinator abundance but was soon overridden by increasing ovule desiccation due to summer drought. Successful seed production was mostly confined to a brief period near the end of the flowering season. Adverse weather during this period in the second study year resulted in a threefold bud and flower mortality and a 50% decrease of fruit production. Spring rainfalls in southwestern Spain have diminished more than 30% through past decades leading to an earlier onset of summer drought. This trend and its adverse effects on seed production may contribute to explaining the recent decline of F. alnus at its southwestern range limit. © Springer-Verlag 2005.Peer Reviewe
How Universal are the Young Cluster Sequences? - the Cases of LMC, SMC, M83 and the Antennae
Aims.Recently a new analysis of cluster observations in the Milky Way found
evidence that clustered star formation may work under tight constraints with
respect to cluster size and density, implying the presence of just two
sequences of young massive cluster. These two types of clusters each expand at
different rates with cluster age. Methods. Here we investigate whether similar
sequences exist in other nearby galaxies. Results:We find that while for the
extragalactic young stellar clusters the overall trend in the cluster-density
scaling is quite comparable to the relation obtained for Galactic clusters,
there are also possible difference. For the LMC and SMC clusters the densities
are below the Galactic data points and/or the core radii are smaller than those
of data points with comparable density. For M83 and the Antenna clusters the
core radii are possibly comparable to the Galactic clusters but it is not clear
whether they exhibit similar expansion speeds. These findings should serve as
an incentive to perform more systematic observations and analysis to answer the
question of a possible similarity between young galactic and extragalactic star
clusters sequences.Comment: 6 pages, 4 figures, A&A in pres
Analysis of reasons of insufficient wear resistance of pumps waterjet mixes
Проведен анализ недостаточной износостойкости деталей насосов для гидроабразивных смесей. Предложены пути повышения износостойкости деталей проточной части насосов на основе применения штампованных деталей взамен литых, а также композиционных материалов на основе углерод‐углерода.The analysis of the lack of wear parts pumps waterjet mixtures. Ways of improving the durability of the parts flow pump through the use of forged parts to replace the cast, as well as composite materials based on carbon‐carbon
The addition of rituximab to chemotherapy improves overall survival in mantle cell lymphoma—a pooled trials analysis
Mantle cell lymphoma (MCL) is a distinct subtype of B-cell lymphoma and commonly used induction immunochemotherapies include the anti-CD20 antibody rituximab. However, efficacy data for rituximab regarding overall survival (OS) in first line MCL therapy remain conflicting.
We report long-term outcomes of a pooled trials analysis comparing Cyclophosphamide, Doxorubicine, Vincristine, Prednisone (CHOP) to R-CHOP in MCL to confirm efficacy on failure free survival (FFS) and OS in relevant subgroups. Untreated, adult MCL patients of two prospective trials assigned to CHOP or R-CHOP were included. Primary endpoints were FFS and OS, secondary endpoints included duration of response (DOR), secondary malignancies and OS after relapse. Between 1996 and 2003, 385 MCL patients were assigned to CHOP (201) or R-CHOP (184). After a median follow-up of 13.4 years, the addition of Rituximab significantly improved FFS (1.36 vs. 2.07 years, HR 0.62 (0.50–0.77)), OS (4.84 vs. 5.81 years, HR 0.78 (0.61–0.99)) and DOR (1.48 vs. 2.08 years, HR 0.67 (0.53–0.86)). Furthermore, Rituximab improved survival across different MCL risk groups. In a post-hoc analysis of OS after relapse comparing patients receiving chemotherapy with / without rituximab, rituximab maintained efficacy with a median OS of 3.10 vs. 2.11 years (HR 0.70, 0.54–0.91). The rate of secondary malignancies was 0.5 and 3.9% for hematological and 7 and 8% for non-hematological malignancies for CHOP and R-CHOP patients, respectively. We present mature results of a pooled MCL cohort, demonstrating prolonged FFS, OS and DOR for the combined immuno-chemotherapy, confirming the standard of care in first line treatment
Low-dose Decitabine Vs best supportive care in older patients with AML and low blast counts: results of a subgroup analysis of the randomized phase III study 06011 of the EORTC leukemia cooperative group and german MDS study group
Early Versus Late Allogeneic Hematopoietic Cell Transplantation in Patients with AML - Results From the Randomized AML 2003 Trial
HLA-DRB3/4/5 Matching Improves Outcome of Unrelated Hematopoietic Stem Cell Transplantation
The HLA-DRB3/4/5 loci are closely linked to the HLA-DRB1 gene. Mismatches in these
loci occur with a frequency of about 8%–12% in otherwise 10/10 HLA-matched transplant
pairs. There is preliminary evidence that these disparities may associate with increased
acute graft-versus-host disease (GvHD) rates. The aim of this study was to analyze a large
cohort of German patients and their donors for HLA-DRB3/4/5 compatibility and to
correlate the HLA-DRB3/4/5 matching status with the outcome of unrelated
hematopoietic stem cell transplantation (uHSCT). To this end, 3,410 patients and their
respective donors were HLA-DRB3/4/5 and HLA-DPB1 typed by amplicon-based nextgeneration
sequencing (NGS). All patients included received their first allogeneic
transplant for malignant hematologic diseases between 2000 and 2014. Mismatches in
the antigen recognition domain (ARD) of HLA-DRB3/4/5 genes were correlated with
clinical outcome. HLA-DRB3/4/5 incompatibility was seen in 12.5% (n = 296) and 17.8%
(n = 185) of the 10/10 and 9/10 HLA-matched cases, respectively. HLA-DRB3/4/5
mismatches in the ARD associated with a worse overall survival (OS), as shown in
univariate (5-year OS: 46.1% vs. 39.8%, log-rank p = 0.038) and multivariate analyses
[hazard ratio (HR) 1.25, 95% CI 1.02–1.54, p = 0.034] in the otherwise 10/10 HLAmatched
subgroup. The worse outcome was mainly driven by a significantly higher nonrelapse
mortality (HR 1.35, 95% CI 1.05–1.73, p = 0.017). In the 9/10 HLA-matched
cases, the effect was not statistically significant. Our study results suggest that
mismatches within the ARD of HLA-DRB3/4/5 genes significantly impact the outcome
of otherwise fully matched uHSCT and support their consideration upon donor selection in
the future
HLA-DRB3/4/5 Matching Improves Outcome of Unrelated Hematopoietic Stem Cell Transplantation
The HLA-DRB3/4/5 loci are closely linked to the HLA-DRB1 gene. Mismatches in these
loci occur with a frequency of about 8%–12% in otherwise 10/10 HLA-matched transplant
pairs. There is preliminary evidence that these disparities may associate with increased
acute graft-versus-host disease (GvHD) rates. The aim of this study was to analyze a large
cohort of German patients and their donors for HLA-DRB3/4/5 compatibility and to
correlate the HLA-DRB3/4/5 matching status with the outcome of unrelated
hematopoietic stem cell transplantation (uHSCT). To this end, 3,410 patients and their
respective donors were HLA-DRB3/4/5 and HLA-DPB1 typed by amplicon-based nextgeneration
sequencing (NGS). All patients included received their first allogeneic
transplant for malignant hematologic diseases between 2000 and 2014. Mismatches in
the antigen recognition domain (ARD) of HLA-DRB3/4/5 genes were correlated with
clinical outcome. HLA-DRB3/4/5 incompatibility was seen in 12.5% (n = 296) and 17.8%
(n = 185) of the 10/10 and 9/10 HLA-matched cases, respectively. HLA-DRB3/4/5
mismatches in the ARD associated with a worse overall survival (OS), as shown in
univariate (5-year OS: 46.1% vs. 39.8%, log-rank p = 0.038) and multivariate analyses
[hazard ratio (HR) 1.25, 95% CI 1.02–1.54, p = 0.034] in the otherwise 10/10 HLAmatched
subgroup. The worse outcome was mainly driven by a significantly higher nonrelapse
mortality (HR 1.35, 95% CI 1.05–1.73, p = 0.017). In the 9/10 HLA-matched
cases, the effect was not statistically significant. Our study results suggest that
mismatches within the ARD of HLA-DRB3/4/5 genes significantly impact the outcome
of otherwise fully matched uHSCT and support their consideration upon donor selection in
the future
The Human Leukocyte Antigen-DPB1 Degree of Compatibility Is Determined by Its Expression Level and Mismatch Permissiveness: A German Multicenter Analysis
T-cell epitope matching according to the TCE3 algorithm classifies HLA-DPB1 mismatches in permissive and non-permissive. This classification has been shown to be predictive for mortality and acute GvHD (aGvHD) events in large international cohorts. We retrospectively genotyped HLA-DPB1 in 3523 patients transplanted in Germany between 2000 and 2014 and in their unrelated donors using an Illumina amplicon-NGS based assay. Aim of the study was to evaluate DP-compatibility beyond the established TCE3 algorithm by assessing the combined effect of several DP-mismatch parameters on post-transplant outcome. We implemented an extended DP-mismatch assessment model where TCE3, DP allotype expression with respect to rs9277534, mismatch vector and number of mismatches were conjointly taken into consideration. In this model, non-permissive HLA-DPB1 mismatches showed significantly increased aGvHD risk if they were accompanied by two HLA-DPB1 mismatches in GvH direction (HR: 1.46) or one mismatched highly expressed patient allotype (HR: 1.53). As previously reported, non-permissive HLA-DPB1 mismatches associated with a significantly higher risk of aGvHD and non-relapse mortality (HR 1.36 and 1.21, respectively), which in turn translated into worse GvHD and relapse free survival (HR 1.13). Effects on GvL and GvHD appeared strongest in GvH-directed non-permissive mismatches. Our study results support the consideration of additional HLA-DPB1 mismatch parameters along with the established TCE3 matching algorithm for refinement of future donor selection. In particular, our findings suggest that DP non-permissiveness associated with two HLA-DPB1 mismatches or at least on highly expressed mismatched patient allotype should be avoided
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