712 research outputs found
Radial Color Gradients in K+A Galaxies in Distant Clusters of Galaxies
Galaxies in rich clusters with z 0.3 are observed to have a higher
fraction of photometrically blue galaxies than their nearby counterparts. This
raises the important question of what environmental effects can cause the
termination of star formation between z 0.3 and the present. The star
formation may be truncated due to ram-pressure stripping, or the gas in the
disk may be depleted by an episode of star formation caused by some external
perturbation. To help resolve this issue, surface photometry was carried out
for a total of 70 early-type galaxies in the cluster Cl1358+62, at z
0.33, using two-color images from the Hubble Archive. The galaxies were divided
into two categories based on spectroscopic criteria: 24 are type K+A (e.g.,
strong Balmer lines, with no visible emission lines), while the remaining 46
are in the control sample with normal spectra. Radial color profiles were
produced to see if the K+A galaxies show bluer nuclei in relation to their
surrounding disks. Specifically, a linear gradient was fit to the radial color
profile of each galaxy. We find that the K+A galaxies on average tend to have
slightly bluer gradients towards the center than the normals. A
Kolmogorov-Smirnov two-sample test has been applied to the two sets of color
gradients. The result of the test indicates that there is only a 2%
probability that the K+A and normal samples are drawn from the same parent
distribution. There is a possible complication from a trend in the apparent
magnitude vs. color gradient relation, but overall our results favor the
centralized star formation scenario as an important process in the evolution of
galaxies in dense clusters.Comment: 16 pages, 12 figures, accepted for publication in A
Abstracts of presentations on plant protection issues at the xth international congress of virology: August 11-16,1996 Binyanei haOoma, Jerusalem, Israel Part 2 Plenary Lectures
The regulation of IL-10 expression
Interleukin (IL)-10 is an important immunoregulatory cytokine and an understanding of how IL-10 expression is controlled is critical in the design of immune intervention strategies. IL-10 is produced by almost all cell types within the innate (including macrophages, monocytes, dendritic cells (DCs), mast cells, neutrophils, eosinophils and natural killer cells) and adaptive (including CD4(+) T cells, CD8(+) T cells and B cells) immune systems. The mechanisms of IL-10 regulation operate at several stages including chromatin remodelling at the Il10 locus, transcriptional regulation of Il10 expression and post-transcriptional regulation of Il10 mRNA. In addition, whereas some aspects of Il10 gene regulation are conserved between different immune cell types, several are cell type- or stimulus-specific. Here, we outline the complexity of IL-10 production by discussing what is known about its regulation in macrophages, monocytes, DCs and CD4(+) T helper cells
Genetic Variation and Recurrent Haplotypes on Chromosome 6q23-25 Risk Locus in Familial Lung Cancer
Although lung cancer is known to be caused by environmental factors, it has also been shown to have genetic components, and the genetic etiology of lung cancer remains understudied. We previously identified a lung cancer risk locus on 6q23-25 using microsatellite data in families with a history of lung cancer. To further elucidate that signal, we performed targeted sequencing on nine of our most strongly linked families. Two-point linkage analysis of the sequencing data revealed that the signal was heterogeneous and that different families likely had different risk variants. Three specific haplotypes were shared by some of the families: 6q25.3-26 in families 42 and 44, 6q25.2-25.3 in families 47 and 59, and 6q24.2-25.1 in families 30, 33, and 35. Region-based logarithm of the odds scores and expression data identified the likely candidate genes for each haplotype overlap
Whole Exome Sequencing of Highly Aggregated Lung Cancer Families Reveals Linked Loci for Increased Cancer Risk on Chromosomes 12q, 7p, and 4q
BACKGROUND: Lung cancer kills more people than any other cancer in the United States. In addition to environmental factors, lung cancer has genetic risk factors as well, though the genetic etiology is still not well understood. We have performed whole exome sequencing on 262 individuals from 28 extended families with a family history of lung cancer.
METHODS: Parametric genetic linkage analysis was performed on these samples using two distinct analyses-the lung cancer only (LCO) analysis, where only patients with lung cancer were coded as affected, and the all aggregated cancers (AAC) analysis, where other cancers seen in the pedigree were coded as affected.
RESULTS: The AAC analysis yielded a genome-wide significant result at rs61943670 in POLR3B at 12q23.3. POLR3B has been implicated somatically in lung cancer, but this germline finding is novel and is a significant expression quantitative trait locus in lung tissue. Interesting genome-wide suggestive haplotypes were also found within individual families, particularly near SSPO at 7p36.1 in one family and a large linked haplotype spanning 4q21.3–28.3 in a different family. The 4q haplotype contains potential causal rare variants in DSPP at 4q22.1 and PTPN13 at 4q21.3.
CONCLUSIONS: Regions on 12q, 7p, and 4q are linked to increased cancer risk in highly aggregated lung cancer families, 12q across families and 7p and 4q within a single family.
IMPACT: Functional work on these genes is planned for future studies and if confirmed would lead to potential biomarkers for risk in cancer
Multiple Merging Events in the Double Cluster A3128/A3125
Multi-fiber spectroscopy has been obtained for 335 galaxies in the field of
the double cluster A3128/A3125, using the 2dF multi-fiber positioner on the
AAT. A total of 532 objects in the double cluster now have known redshifts. We
have also obtained a 20 ks Chandra ACIS-I image of A3128 and radio imaging with
the MOST and the ATCA. The spatial-kinematic distribution of redshifts in the
field of A3128/A3125, when combined with the Chandra image of A3128, reveals a
variety of substructures present in the galaxy distribution and in the hot ICM.
The most striking large-scale feature in the galaxy distribution is an
underpopulated redshift zone ~4000 km/s on either side of the cluster velocity
at ~17500 km/s. We attribute this depletion zone to the effect of the extensive
Horologium-Reticulum Supercluster (HRS), within which A3128/A3125 is embedded.
In addition, numerous smaller groups of galaxies are identified, particularly
in the underpopulated region within +-4000 km/s of the cluster redshift. Due to
the large gravitational influence of the HRS, these groups arrive at A3128 with
a very high (hypersonic) infall velocity. Two of these groups appear as
elongated filaments in position-velocity diagrams, indicating that they are
tidally distended groups which have been disrupted after a close passage
through A3128. We have identified a primary NE-SW merger axis connecting A3128
with A3125, along which the filaments are also oriented. In addition, the
Chandra image reveals that the X-ray emission is split into two components,
each with very small core radii, that are separated by ~1 Mpc along the NE-SW
axis. We propose that the complex X-ray morphology is likely the result of the
hypersonic infall of a relatively small group into A3128. The group produces a
major disruption in the ICM due to its high infall velocity.Comment: 52 pages, 27 figures, accepted for publication in the Astronomical
Journal. A more easily down-loaded version with full resolution figures is
available at http://www.physics.unc.edu/~jim/a3128/LANL
Implementation of Whole-Body MRI (MY-RADS) within the OPTIMUM/MUKnine multi-centre clinical trial for patients with myeloma.
BACKGROUND: Whole-body (WB) MRI, which includes diffusion-weighted imaging (DWI) and T1-w Dixon, permits sensitive detection of marrow disease in addition to qualitative and quantitative measurements of disease and response to treatment of bone marrow. We report on the first study to embed standardised WB-MRI within a prospective, multi-centre myeloma clinical trial (IMAGIMM trial, sub-study of OPTIMUM/MUKnine) to explore the use of WB-MRI to detect minimal residual disease after treatment. METHODS: The standardised MY-RADS WB-MRI protocol was set up on a local 1.5 T scanner. An imaging manual describing the MR protocol, quality assurance/control procedures and data transfer was produced and provided to sites. For non-identical scanners (different vendor or magnet strength), site visits from our physics team were organised to support protocol optimisation. The site qualification process included review of phantom and volunteer data acquired at each site and a teleconference to brief the multidisciplinary team. Image quality of initial patients at each site was assessed. RESULTS: WB-MRI was successfully set up at 12 UK sites involving 3 vendor systems and two field strengths. Four main protocols (1.5 T Siemens, 3 T Siemens, 1.5 T Philips and 3 T GE scanners) were generated. Scanner limitations (hardware and software) and scanning time constraint required protocol modifications for 4 sites. Nevertheless, shared methodology and imaging protocols enabled other centres to obtain images suitable for qualitative and quantitative analysis. CONCLUSIONS: Standardised WB-MRI protocols can be implemented and supported in prospective multi-centre clinical trials. Trial registration NCT03188172 clinicaltrials.gov; registration date 15th June 2017 https://clinicaltrials.gov/ct2/show/study/NCT03188172
Impact of Multiple COVID-19 Waves on Gynaecological Cancer Services in the UK
Background: This study aimed to assess the impact of multiple COVID-19 waves on UK gynaecological-oncology services. Methods: An online survey was distributed to all UK-British-Gynaecological-Cancer-Society members during three COVID-19 waves from 2020 to2022. Results: In total, 51 hospitals (including 32 cancer centres) responded to Survey 1, 42 hospitals (29 centres) to Survey 2, and 39 hospitals (30 centres) to Survey 3. During the first wave, urgent referrals reportedly fell by a median of 50% (IQR = 25–70%). In total, 49% hospitals reported reduced staffing, and the greatest was noted for trainee doctors, by a median of 40%. Theatre capacity was reduced by a median of 40%. A median of 30% of planned operations was postponed. Multidisciplinary meetings were completely virtual in 39% and mixed in 65% of the total. A median of 75% of outpatient consultations were remote. By the second wave, fewer hospitals reported staffing reductions, and there was a return to pre-pandemic urgent referrals and multidisciplinary workloads. Theatre capacity was reduced by a median of 10%, with 5% of operations postponed. The third wave demonstrated worsening staff reductions similar to Wave 1, primarily from sickness. Pre-pandemic levels of urgent referrals/workload continued, with little reduction in surgical capacity. Conclusion: COVID-19 led to a significant disruption of gynaecological-cancer care across the UK, including reduced staffing, urgent referrals, theatre capacity, and working practice changes. Whilst disruption eased and referrals/workloads returned to normal, significant staff shortages remained in 2022, highlighting persistent capacity constraints.</p
Cost-efficiency assessment of Advanced Life Support (ALS) courses based on the comparison of advanced simulators with conventional manikins
<p>Abstract</p> <p>Background</p> <p>Simulation is an essential tool in modern medical education. The object of this study was to assess, in cost-effective measures, the introduction of new generation simulators in an adult life support (ALS) education program.</p> <p>Methods</p> <p>Two hundred fifty primary care physicians and nurses were admitted to ten ALS courses (25 students per course). Students were distributed at random in two groups (125 each). Group A candidates were trained and tested with standard ALS manikins and Group B ones with new generation emergency and life support integrated simulator systems.</p> <p>Results</p> <p>In group A, 98 (78%) candidates passed the course, compared with 110 (88%) in group B (p < 0.01). The total cost of conventional courses was €7689 per course and the cost of the advanced simulator courses was €29034 per course (p < 0.001). Cost per passed student was €392 in group A and €1320 in group B (p < 0.001).</p> <p>Conclusion</p> <p>Although ALS advanced simulator systems may slightly increase the rate of students who pass the course, the cost-effectiveness of ALS courses with standard manikins is clearly superior.</p
90Y Radioembolization for Hepatic Malignancy in Patients with Previous Biliary Intervention: Multicenter Analysis of Hepatobiliary Infections
PurposeTo determine the frequency of hepatobiliary infections after transarterial radioembolization (TARE) with yttrium 90 (90Y) in patients with liver malignancy and a history of biliary intervention.Materials and MethodsFor this retrospective study, records of all consecutive patients with liver malignancy and history of biliary intervention treated with TARE at 14 centers between 2005 and 2015 were reviewed. Data regarding liver function, 90Y dosimetry, antibiotic prophylaxis, and bowel preparation prophylaxis were collected. Primary outcome was development of hepatobiliary infection.ResultsOne hundred twenty-six patients (84 men, 42 women; mean age, 68.8 years) with primary (n = 39) or metastatic (n = 87) liver malignancy and history of biliary intervention underwent 180 procedures with glass (92 procedures) or resin (88 procedures) microspheres. Hepatobiliary infections (liver abscesses in nine patients, cholangitis in five patients) developed in 10 of the 126 patients (7.9%) after 11 of the 180 procedures (6.1%; nine of those procedures were performed with glass microspheres). All patients required hospitalization (median stay, 12 days; range, 2–113 days). Ten patients required percutaneous abscess drainage, three patients underwent endoscopic stent placement and stone removal, and one patient needed insertion of percutaneous biliary drains. Infections resolved in five patients, four patients died (two from infection and two from cancer progression while infection was being treated), and one patient continued to receive suppressive antibiotics. Use of glass microspheres (P = .02), previous liver resection or ablation (P = .02), and younger age (P = .003) were independently predictive of higher infection risk.ConclusionInfectious complications such as liver abscess and cholangitis are uncommon but serious complications of transarterial radioembolization with 90Y in patients with liver malignancy and a history of biliary intervention.© RSNA, 2018Online supplemental material is available for this article
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