165 research outputs found
Complex Patterns of Metabolic and Ca<sup>2+</sup> Entrainment in Pancreatic Islets by Oscillatory Glucose
Glucose-stimulated insulin secretion is pulsatile and driven by intrinsic oscillations in metabolism, electrical activity, and Ca(2+) in pancreatic islets. Periodic variations in glucose can entrain islet Ca(2+) and insulin secretion, possibly promoting interislet synchronization. Here, we used fluorescence microscopy to demonstrate that glucose oscillations can induce distinct 1:1 and 1:2 entrainment of oscillations (one and two oscillations for each period of exogenous stimulus, respectively) in islet Ca(2+), NAD(P)H, and mitochondrial membrane potential. To our knowledge, this is the first demonstration of metabolic entrainment in islets, and we found that entrainment of metabolic oscillations requires voltage-gated Ca(2+) influx. We identified diverse patterns of 1:2 entrainment and showed that islet synchronization during entrainment involves adjustments of both oscillatory phase and period. All experimental findings could be recapitulated by our recently developed mathematical model, and simulations suggested that interislet variability in 1:2 entrainment patterns reflects differences in their glucose sensitivity. Finally, our simulations and recordings showed that a heterogeneous group of islets synchronized during 1:2 entrainment, resulting in a clear oscillatory response from the collective. In summary, we demonstrate that oscillatory glucose can induce complex modes of entrainment of metabolically driven oscillations in islets, and provide additional support for the notion that entrainment promotes interislet synchrony in the pancreas
Ideal MHD theory of low-frequency Alfven waves in the H-1 Heliac
A part analytical, part numerical ideal MHD analysis of low-frequency Alfven
wave physics in the H-1 stellarator is given. The three-dimensional,
compressible ideal spectrum for H-1 is presented and it is found that despite
the low beta (approx. 10^-4) of H-1 plasmas, significant Alfven-acoustic
interactions occur at low frequencies. Several quasi-discrete modes are found
with the three-dimensional linearised ideal MHD eigenmode solver CAS3D,
including beta-induced Alfven eigenmode (BAE)- type modes in beta-induced gaps.
The strongly shaped, low-aspect ratio magnetic geometry of H-1 causes CAS3D
convergence difficulties requiring the inclusion of many Fourier harmonics for
the parallel component of the fluid displacement eigenvector even for shear
wave motions. The highest beta-induced gap reproduces large parts of the
observed configurational frequency dependencies in the presence of hollow
temperature profiles
Complex Patterns of Metabolic and Ca<sup>2+</sup> Entrainment in Pancreatic Islets by Oscillatory Glucose
Glucose-stimulated insulin secretion is pulsatile and driven by intrinsic oscillations in metabolism, electrical activity, and Ca(2+) in pancreatic islets. Periodic variations in glucose can entrain islet Ca(2+) and insulin secretion, possibly promoting interislet synchronization. Here, we used fluorescence microscopy to demonstrate that glucose oscillations can induce distinct 1:1 and 1:2 entrainment of oscillations (one and two oscillations for each period of exogenous stimulus, respectively) in islet Ca(2+), NAD(P)H, and mitochondrial membrane potential. To our knowledge, this is the first demonstration of metabolic entrainment in islets, and we found that entrainment of metabolic oscillations requires voltage-gated Ca(2+) influx. We identified diverse patterns of 1:2 entrainment and showed that islet synchronization during entrainment involves adjustments of both oscillatory phase and period. All experimental findings could be recapitulated by our recently developed mathematical model, and simulations suggested that interislet variability in 1:2 entrainment patterns reflects differences in their glucose sensitivity. Finally, our simulations and recordings showed that a heterogeneous group of islets synchronized during 1:2 entrainment, resulting in a clear oscillatory response from the collective. In summary, we demonstrate that oscillatory glucose can induce complex modes of entrainment of metabolically driven oscillations in islets, and provide additional support for the notion that entrainment promotes interislet synchrony in the pancreas
an ALWP-EBMT study
Background Allogeneic stem cell transplantation is the only curative option
for patients with acute myeloid leukemia (AML) experiencing relapse. Either
matched sibling donor (MSD) or unrelated donor (UD) is indicated. Methods We
analyzed 1554 adults with AML transplanted from MSD (n = 961) or UD (n = 593,
HLA-matched 10/10, n = 481; 9/10, n = 112). Compared to MSD, UD recipients
were older (49 vs 52 years, p = 0.001), transplanted more recently (2009 vs
2006, p = 0.001), and with a longer interval to transplant (10 vs 9 months, p
= 0.001). Conditioning regimen was more frequently myeloablative for patients
transplanted with a MSD (61 vs 46 %, p = 0.001). Median follow-up was 28
(range 3–157) months. Results Cumulative incidence (CI) of neutrophil
engraftment (p = 0.07), grades II–IV acute GVHD (p = 0.11), chronic GVHD (p =
0.9), and non-relapse mortality (NRM, p = 0.24) was not different according to
the type of donor. At 2 years, CI of relapse (relapse incidence (RI)) was 57
vs 49 % (p = 0.001). Leukemia-free survival (LFS) at 2 years was 21 vs 26 % (p
= 0.001), and overall survival (OS) was 26 vs 33 % (p = 0.004) for MSD vs UD,
respectively. Chronic GVHD as time-dependent variable was associated with
lower RI (HR 0.78, p = 0.05), higher NRM (HR 1.71, p = 0.001), and higher OS
(HR 0.69, p = 0.001). According to HLA match, RI was 57 vs 50 vs 45 %, (p =
0.001) NRM was 23 vs 23 vs 29 % (p = 0.26), and LFS at 2 years was 21 vs 27 vs
25 % (p = 0.003) for MSD, 10/10, and 9/10 UD, respectively. In multivariate
analysis adjusted for differences between the two groups, UD was associated
with lower RI (HR 0.76, p = 0.001) and higher LFS (HR 0.83, p = 0.001)
compared to MSD. Interval between diagnosis and transplant was the other
factor associated with better outcomes (RI (HR 0.62, p < 0.001) and LFS (HR
0.67, p < 0.001)). Conclusions Transplantation using UD was associated with
better LFS and lower RI compared to MSD for high-risk patients with AML
transplanted in first relapse
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
Mrk 609: resolving the circum-nuclear structure with near-infrared integral field spectroscopy
We present first results of near infrared J and H+K ESO-SINFONI integral
field spectroscopy of the composite starburst/Seyfert 1.8 galaxy Mrk 609. The
data were taken during the science verification period of SINFONI. We aim to
investigate the morphology and excitation conditions within the central 2 kpc.
Additional Nobeyama 45 m CO(1-0) data are presented, which we used to estimate
the molecular gas mass. The source was selected from a sample of adaptive
optics suitable, SDSS/ROSAT based, X-ray bright AGN with redshifts of 0.03 < z
< 1. This sample allows for a detailed study of the NIR properties of the
nuclear and host environments with high spectral and spatial resolution. Our
NIR data reveal a complex emission-line morphology, possibly associated with a
nuclear bar seen in the reconstructed continuum images. The detections of
[SiVI] and a broad Pa alpha component are clear indicators for the presence of
an accreting super-massive black hole at the center of Mrk 609. In agreement
with previous observations we find that the circum-nuclear emission is not
significantly extincted. The analysis of the high angular resolution
rotational-vibrational molecular hydrogen and forbidden [FeII] emission reveals
a LINER character of the nucleus. The large H_2 gas mass deduced from the
CO(1-0) observation provides the fuel needed to feed the starburst and Seyfert
activity in Mrk 609. High angular resolution imaging spectroscopy provides an
ideal tool to resolve the nuclear and starburst contribution in active
galaxies. We show that Mrk 609 exhibits LINER features, that appear to be
hidden in larger aperture visible/NIR spectra.Comment: published by A&A, 19 pages, 16 figures, version with high resolution
figures is available via http://www.ph1.uni-koeln.de/~zuther/mrk609.pd
Organ complications after CD19 CAR T-cell therapy for large B cell lymphoma: a retrospective study from the EBMT transplant complications and lymphoma working party.
We investigated ≥ grade 3 (CTC-AE) organ toxicities for commercial CD19 chimeric antigen receptor T cell (CAR-T cell) products in 492 patients (Axi-Cel; n = 315; Tisa-Cel; n = 177) with Large B-cell Lymphoma in the European Society for Blood and Marrow Transplantation (EBMT) CAR-T registry. The incidence of ≥ grade 3 organ toxicities during the first 100 days after CAR-T was low and the most frequent were: renal (3.0%), cardiac (2.3%), gastro-intestinal (2.3%) and hepatic (1.8%). The majority occurred within three weeks after CAR-T cell therapy. Overall survival was 83.1% [79.8-86.5; 95% CI] at 3 months and 53.5% [49-58.4; 95% CI] at one year after CAR-T. The most frequent cause of death was tumour progression (85.1%). Non-relapse mortality was 3.1% [2.3-4.1; 95% CI] at 3 months and 5.2% [4.1-6.5; 95% CI] at one year after CAR-T. The most frequent causes of non-relapse mortality were cell-therapy-related toxicities including organ toxicities (6.4% of total deaths) and infections (4.4% of total deaths). Our data demonstrates good safety in the European real-world setting
Outcome of Allogeneic Transplantation for Mature T-cell Lymphomas: Impact of Donor Source and Disease Characteristics
Mature T-cell lymphomas constitute the most common indication for allogeneic hematopoietic cell transplantation (allo-HCT) of all lymphomas. Large studies evaluating contemporary outcomes of allo-HCT in mature T-cell lymphomas relative to commonly used donor sources are not available. Included in this registry study were adult patients who had undergone allo-HCT for anaplastic large cell lymphoma, angioimmunoblastic T-cell lymphoma (AITL), or peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) between 2008 and 2018. Hematopoietic cell transplantation (HCT) platforms compared were posttransplant cyclophosphamidebased haploidentical (haplo-)HCT, matched sibling donor (MSD) HCT, matched unrelated donor HCT with in vivo T-cell depletion (MUD TCD+), and matched unrelated donor HCT without in vivo T-cell depletion (MUD TCD-). Coprimary end points were overall survival (OS) and progression-free survival (PFS); secondary end points included nonrelapse mortality (NRM), and relapse/progression incidence (RI). A total of 1942 patients were eligible (237 haplo-HCT; 911 MSD; 468 MUD TCD+; 326 MUD TCD-). Cohorts were comparable for baseline characteristics with the exception of higher proportions of patients with decreased performance status (PS) and marrow graft recipients in the haplo-HCT group. Using univariate and multivariate comparisons, OS, PFS, RI, and NRM were not significantly different among the haplo-HCT, MSD, MUD TCD+, and MUD TCD- cohorts, with 3-year OS and PFS of 60%, 63%, 59%, and 64%, respectively, and 50%, 50%, 48%, and 52%, respectively. Significant predictors of inferior OS and PFS on multivariate analysis were active disease status at HCT and decreased PS. AITL was associated with significantly reduced relapse risk and better PFS compared with PTCL-NOS. Allo-HCT can provide durable PFS in patients with mature T-cell lymphoma (TCL). Outcomes of haplo-HCT were comparable to those of matched donor allo-HCT
Final Evaluation of a Clinical Phase III Trial Comparing Treosulfan to Busulfan-Based Conditioning Therapy Prior to Allogeneic Hematopoietic Stem Cell Transplantation of Adult Acute Myeloid Leukemia and Myelodysplastic Syndrome Patients Ineligible to Standard Myeloablative Regimens
Background Allogeneic hematopoietic stem cell transplantation (HCT) remains a challenge in elderly and comorbid AML and MDS patients. This patient population is at increased risk for non-relapse mortality (NRM) when treated with standard myeloablative conditioning and was selected to compare a newly developed treosulfan-based with a well-established reduced intensity busulfan-based preparative regimen in a prospective randomized clinical phase III trial. Methods Adult patients with AML in remission or MDS scheduled for HCT from matched related or unrelated donors, aged ≥50 years or with a comorbidity index (HCT-CI) of >2 were enrolled by a central stratified randomization procedure. Treatment arms consisted of intravenous (IV) treosulfan (10 g/m²/day [d-4 to d-2]) or IV busulfan (3.2 mg/kg/day [d-4 to d-3]), both combined with IV fludarabine (30 mg/m²/day [d-6 to d-2]). The primary objective was to compare event-free survival (EFS) at two years with relapse/progression of disease, graft failure, or death reported as events. Secondary endpoints were safety evaluation (according to CTCAE v4.03), engraftment, chimerism, overall survival (OS), relapse/progression incidence (RI), NRM and acute or chronic GvHD. After a previously conducted confirmatory interim analysis (based on 476 patients), which resulted in early termination of patient accrual due to significant non-inferiority of treosulfan treatment with improved EFS, NRM and OS (Beelen et al., ASH 2017), results of the final analysis of all 570 randomized patients including post surveillance data are provided here. Results Median age of the 551 patients (352 AML; 199 MDS) included in the full analysis set (268 treosulfan; 283 busulfan) was 60 years (range: 31, 70). Frequencies of early adverse events (d-6 to d+28) and incidences of acute and chronic GvHD were largely comparable between the two regimens, while extensive chronic GvHD was numerically in favor of treosulfan (19.7% vs. 26.7%; p=0.0750). Primary neutrophil recovery at day +28 was comparable, while the rate of complete donor-type chimerism (day +28) was higher after treosulfan (93.2% vs. 83.3%; p Conclusions Final evaluation of this phase III trial substantiates the previous confirmatory analysis resulting in significantly improved survival after treosulfan-based conditioning. Due to the reduction of NRM a major clinical benefit of the new treosulfan conditioning regimen was demonstrated in the selected AML/MDS patient population
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