83 research outputs found
Oxidative stress and partial migration in brown trout (Salmo trutta)
During migration, animals are typically limited by their endogenous energetic resources that must be allocated to the physiological costs associated with locomotion, as well as avoiding and (or) compensating for oxidative stress. To date, there have been few attempts to understand the role of oxidative status in migration biology, particularly in fish. Semi-anadromous brown trout (Salmo trutta L., 1758) exhibit partial migration, where some individuals smoltify and migrate to sea, and others become stream residents, providing us with an excellent model to investigate the link between oxidative stress and migration. Using the brown trout, we obtained blood samples from juveniles from a coastal stream in Denmark in the fall prior to peak seaward migration that occurs in the spring, and assayed for antioxidant capacity (oxygen radical absorbance capacity) and oxidative stress levels (ratio of oxidized to reduced glutathione). We found that individuals that migrated had higher antioxidant capacity than residents and that future migration date was negatively correlated with both antioxidant capacity and body length in the fall. This study provides the first evidence that oxidative status is associated with migration strategy and timing, months in advance of the actual migration, and provides insight into the role of oxidative status in animal migration. </jats:p
Impact of natural killer cells on outcomes after allogeneic hematopoietic stem cell transplantation: A systematic review and meta-analysis.
Background: Natural killer (NK) cells play a vital role in early immune reconstitution following allogeneic hematopoietic stem cell transplantation (HSCT).
Methods: A literature search was performed on PubMed, Cochrane, and Clinical trials.gov through April 20, 2022. We included 21 studies reporting data on the impact of NK cells on outcomes after HSCT. Data was extracted following the PRISMA guidelines. Pooled analysis was done using the meta-package (Schwarzer et al.). Proportions with 95% confidence intervals (CI) were computed.
Results: We included 1785 patients from 21 studies investigating the impact of NK cell reconstitution post-HSCT (8 studies/1455 patients), stem cell graft NK cell content (4 studies/185 patients), therapeutic NK cell infusions post-HSCT (5 studies/74 patients), and pre-emptive/prophylactic NK cell infusions post-HSCT (4 studies/77 patients). Higher NK cell reconstitution was associated with a better 2-year overall survival (OS) (high: 77%, 95%CI 0.73-0.82 vs low: 55%, 95%CI 0.37-0.72; n=899), however, pooled analysis for relapse rate (RR) or graft versus host disease (GVHD) could not be performed due to insufficient data. Higher graft NK cell content demonstrated a trend towards a better pooled OS (high: 65.2%, 95%CI 0.47-0.81 vs low: 46.5%, 95%CI 0.24-0.70; n=157), lower RR (high: 16.9%, 95%CI 0.10-0.25 vs low: 33%, 95%CI 0.04-0.72; n=157), and lower acute GVHD incidence (high: 27.6%, 95%CI 0.20-0.36 vs low: 49.7%, 95%CI 0.26-0.74; n=157). Therapeutic NK or cytokine-induced killer (CIK) cell infusions for hematologic relapse post-HSCT reported an overall response rate (ORR) and complete response (CR) of 48.9% and 11% with CIK cell infusions and 82.8% and 44.8% with NK cell infusions, respectively. RR, acute GVHD, and chronic GVHD were observed in 55.6% and 51.7%, 34.5% and 20%, and 20.7% and 11.1% of patients with CIK and NK cell infusions, respectively. Pre-emptive donor-derived NK cell infusions to prevent relapse post-HSCT had promising outcomes with 1-year OS of 69%, CR rate of 42%, ORR of 77%, RR of 28%, and acute and chronic GVHD rates of 24.9% and 3.7%, respectively.
Conclusion: NK cells have a favorable impact on outcomes after HSCT. The optimal use of NK cell infusions post-HSCT may be in a pre-emptive fashion to prevent disease relapse
Genetic structuring across alternative life history tactics and small spatial scales in brown trout (Salmo trutta)
Facultative migration occurs when, in response to prevailing conditions, individuals in a population may (or may not) undertake a migration. The brown trout (Salmo trutta) is a species that exhibits facultative migration, where some individuals within populations may move to mainstem rivers (fluvialâadfluvial migration), lakes (lacustrineâadfluvial migration), estuaries (partial anadromy) or sea (anadromy) to feed, while others remain resident. This study attempts to separate two alternative hypotheses for the population structuring that underpins the expression of facultative migration in this species: (a) that anadromous and nonanadromous fish comprise two gene pools; (b) that individual genetic variation or individual variation in geneâenvironment interactions is responsible for the expression of different lifeâhistory tactics within the same gene pool. The study design involved sampling and analyses of anadromous and nonanadromous brown trout from three independent tributary rivers known to produce (seaârun) trout within the same catchment. Results indicate that, in all cases, population genetic divergence was linked to geographical location and not to lifeâhistory tactics. Two genetically distinct coexisting population pairs were identified in two separate tributaries. Despite similar environmental conditions in both tributaries, the frequency of each lifeâhistory tactic (anadromy vs. nonanadromous) within these population pairs differed significantly. The results of this study support the hypothesis that facultative migration in brown trout is likely to be driven by a quantitative threshold trait, where the threshold value varies both among populations and among individuals within populations
Medical student attitudes and educational interventions to prevent neurophobia: a longitudinal study
Two Chromogranin A-Derived Peptides Induce Calcium Entry in Human Neutrophils by Calmodulin-Regulated Calcium Independent Phospholipase A2
Background: Antimicrobial peptides derived from the natural processing of chromogranin A (CgA) are co-secreted with catecholamines upon stimulation of chromaffin cells. Since PMNs play a central role in innate immunity, we examine responses by PMNs following stimulation by two antimicrobial CgA-derived peptides. Methodology/Principal Findings: PMNs were treated with different concentrations of CgA-derived peptides in presence of several drugs. Calcium mobilization was observed by using flow cytometry and calcium imaging experiments. Immunocytochemistry and confocal microscopy have shown the intracellular localization of the peptides. The calmodulin-binding and iPLA2 activating properties of the peptides were shown by Surface Plasmon Resonance and iPLA2 activity assays. Finally, a proteomic analysis of the material released after PMNs treatment with CgA-derived peptides was performed by using HPLC and Nano-LC MS-MS. By using flow cytometry we first observed that after 15 s, in presence of extracellular calcium, Chromofungin (CHR) or Catestatin (CAT) induce a concentration-dependent transient increase of intracellular calcium. In contrast, in absence of extra cellular calcium the peptides are unable to induce calcium depletion from the stores after 10 minutes exposure. Treatment with 2-APB (2-aminoethoxydiphenyl borate), a store operated channels (SOCs) blocker, inhibits completely the calcium entry, as shown by calcium imaging. We also showed that they activate iPLA2 as the two CaM-binding factors (W7 and CMZ) and that the two sequences can be aligned with the two CaMbinding domains reported for iPLA2. We finally analyzed by HPLC and Nano-LC MS-MS the material released by PMNs following stimulation by CHR and CAT. We characterized several factors important for inflammation and innate immunity. Conclusions/Significance: For the first time, we demonstrate that CHR and CAT, penetrate into PMNs, inducing extracellular calcium entry by a CaM-regulated iPLA2 pathway. Our study highlights the role of two CgA-derived peptides in the active communication between neuroendocrine and immune systems
Comparative analysis of calcineurin-inhibitor-based methotrexate and mycophenolate mofetil-containing regimens for prevention of Graft-versus-Host Disease after reduced intensity conditioning allogeneic transplantation
The combination of a calcineurin inhibitor (CNI) such as tacrolimus (TAC) or cyclosporine (CYSP) with methotrexate (MTX) or with mycophenolate mofetil (MMF) has been commonly used for graft-versus-host disease (GVHD) prophylaxis after reduced-intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (alloHCT), but there are limited data comparing efficacy of the 2 regimens. We evaluated 1564 adult patients who underwent RIC alloHCT for acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL), chronic myelogenous leukemia (CML), and myelodysplastic syndrome (MDS) from 2000 to 2013 using HLA-identical sibling (matched related donor [MRD]) or unrelated donor (URD) peripheral blood graft and received CYSP or TAC with MTX or MMF for GVHD prophylaxis. Primary outcomes of the study were acute and chronic GVHD and overall survival (OS). The study divided the patient population into 4 cohorts based on regimen: MMF-TAC, MMF-CYSP, MTX-TAC, and MTX-CYSP. In the URD group, MMF-CYSP was associated with increased risk of grade II to IV acute GVHD (relative risk [RR], 1.78; P < .001) and grade III to IV acute GVHD (RR, 1.93; P = .006) compared with MTX-TAC. In the URD group, use of MMF-TAC (versus MTX-TAC) lead to higher nonrelapse mortality. (hazard ratio, 1.48; P = .008). In either group, no there was no difference in chronic GVHD, disease-free survival, and OS among the GVHD prophylaxis regimens. For RIC alloHCT using MRD, there are no differences in outcomes based on GVHD prophylaxis. However, with URD RIC alloHCT, MMF-CYSP was inferior to MTX-based regimens for acute GVHD prevention, but all the regimens were equivalent in terms of chronic GVHD and OS. Prospective studies, targeting URD recipients are needed to confirm these results
Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide
Post-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P =.002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P <.001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P =.01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P =.01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide
Post-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P = .002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P < .001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P = .01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P = .01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival
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