188 research outputs found
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Restriction Spectrum Imaging Differentiates True Tumor Progression From Immune-Mediated Pseudoprogression: Case Report of a Patient With Glioblastoma.
Immunotherapy is increasingly used in the treatment of glioblastoma (GBM), with immune checkpoint therapy gaining in popularity given favorable outcomes achieved for other tumors. However, immune-mediated (IM)-pseudoprogression is common, remains poorly characterized, and renders conventional imaging of little utility when evaluating for treatment response. We present the case of a 64-year-old man with GBM who developed pathologically proven IM-pseudoprogression after initiation of a checkpoint inhibitor, and who subsequently developed true tumor progression at a distant location. Based on both qualitative and quantitative analysis, we demonstrate that an advanced diffusion-weighted imaging (DWI) technique called restriction spectrum imaging (RSI) can differentiate IM-pseudoprogression from true progression even when conventional imaging, including standard DWI/apparent diffusion coefficient (ADC), is not informative. These data complement existing literature supporting the ability of RSI to estimate tumor cellularity, which may help to resolve complex diagnostic challenges such as the identification of IM-pseudoprogression
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AAPM medical physics practice guideline 10.a.: Scope of practice for clinical medical physics.
The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline (MPPG) represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiation requires specific training, skills, and techniques as described in each document. As the review of the previous version of AAPM Professional Policy (PP)-17 (Scope of Practice) progressed, the writing group focused on one of the main goals: to have this document accepted by regulatory and accrediting bodies. After much discussion, it was decided that this goal would be better served through a MPPG. To further advance this goal, the text was updated to reflect the rationale and processes by which the activities in the scope of practice were identified and categorized. Lastly, the AAPM Professional Council believes that this document has benefitted from public comment which is part of the MPPG process but not the AAPM Professional Policy approval process. The following terms are used in the AAPM's MPPGs: Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances
Recurrent Lymphocytic Meningitis Positive for Herpes Simplex Virus Type 2
We found the prevalence of recurrent lymphocytic meningitis associated with herpes simplex virus type 2 (HSV-2) was 2.2/100,000 population in Finland during 1996–2006, higher than previous estimates. PCR was most sensitive in detecting HSV-2 DNA from cerebrospinal fluid if the sample was taken 2–5 days after symptom onset
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Agent orange exposure and prostate cancer risk in the million veteran program
BackgroundThe US government considers veterans to have been exposed to Agent Orange if they served in Vietnam while the carcinogen was in use, and these veterans are often deemed at high risk of prostate cancer (PCa). Here, we assess whether presumed Agent Orange exposure is independently associated with increased risk of any metastatic or fatal PCa in a diverse Veteran cohort still alive in the modern era (at least 2011), when accounting for race/ethnicity, family history, and genetic risk.Patients and methodsParticipants in the Million Veteran Program (MVP; enrollment began in 2011) who were on active duty during the Vietnam War era (August 1964-April 1975) were included (n = 301,470). Agent Orange exposure was determined using the US government definition. Genetic risk was assessed via a validated polygenic hazard score. Associations with age at diagnosis of any PCa, metastatic PCa, and death from PCa were assessed via Cox proportional hazards models.Results and interpretationOn univariable analysis, exposure to Agent Orange was not associated with increased PCa (hazard ratio [HR]: 1.02, 95% confidence interval [CI]: 1.00-1.04, p = 0.06), metastatic PCa (HR: 0.98, 95% CI: 0.91-1.05, p = 0.55), or fatal PCa (HR: 0.94, 95% CI: 0.79-1.09, p = 0.41). When accounting for race/ethnicity and family history, Agent Orange exposure was independently associated with slightly increased risk of PCa (HR: 1.06, 95% CI: 1.04-1.09, <10-6) but not with metastatic PCa (HR: 1.07, 95% CI: 0.98-1.15, p = 0.10) or PCa death (HR: 1.02, 95% CI: 0.83-1.23, p = 0.09). Similar results were found when accounting for genetic risk. Agent Orange exposure history may not improve modern PCa risk stratification
Prostate-Specific Antigen Screening and 15-year Prostate Cancer Mortality:A Secondary Analysis of the CAP Randomized Clinical Trial
Key PointsQuestion In men aged 50 to 69 years, does a single invitation for a prostate-specific antigen (PSA) screening test reduce prostate cancer mortality at 15-year follow-up compared with no invitation for testing?Findings In this secondary analysis of a randomized clinical trial of 415 357 men aged 50 to 69 years randomized to a single invitation for PSA screening (n = 195 912) or a control group without PSA screening (n = 219 445) and followed up for a median of 15 years, risk of death from prostate cancer was lower in the group invited to screening (0.69% vs 0.78%; mean difference, 0.09%) compared with the control group.Meaning Compared with no invitation for routine PSA testing, a single invitation for a PSA screening test reduced prostate cancer mortality at a median follow-up of 15 years, but the absolute mortality benefit was small.AbstractIMPORTANCE The Cluster randomized trial of PSA testing for Prostate cancer (CAP) reported no effect of prostate specific antigen (PSA) screening on prostate cancer mortality at median 10-year follow-up (primary outcome), but the long-term effects of PSA screening on prostate cancer mortality remain unclear.OBJECTIVE To evaluate the effect of a single invitation for PSA screening on the pre-specified secondary outcome of prostate cancer-specific mortality at a median of 15 years’ follow-up, compared to a control group not invited for screening. DESIGN, SETTING, PARTICIPANTS Cluster randomized trial of men aged 50-69 identified from 573 primary-care practices in England and Wales. Primary-care practices were randomized between 09/25/2001 and 08/24/2007 and men were enrolled between 01/08/2002 and 01/20/2009. Follow-up was completed on 03/31/2021. INTERVENTION A single invitation for a PSA screening test with subsequent diagnostic tests if PSA≥3.0ng/ml, compared to standard practice (control). MAIN OUTCOMES AND MEASURES The primary outcome was reported previously. Of eight prespecified secondary outcomes, results of four were reported previously. The four remaining pre-specified secondary outcomes at 15-year follow-up were prostate cancer-specific mortality, all-cause mortality, and prostate cancer stage and Gleason grade at diagnosis.RESULTS Of 415,357 randomized men (mean [SD] age: 59.0 [5.6] years), 98% were analyzed in these analyses. Overall, 12,013 and 12,958 men with prostate cancers were diagnosed in the intervention and control groups (15-year cumulative risks 7.1% and 6.9% respectively). At a median 15-year follow-up, 1,199 (0.69%) men in the intervention group and 1,451 (0.78%) men in the control group died of prostate cancer (rate ratio [RR] 0.92 [95% CI 0.85, 0.99]; p=0.03). Compared to the control group, the PSA screening intervention increased detection of low-grade (Gleason score [GS]≤6; 2.2% versus 1.6%;p<0.001) and localized (T1/T2; 3.6% versus 3.1%;p<0.001) disease, but not intermediate (GS=7), high-grade (GS≥8), locally-advanced (T3) or distally-advanced (T4/N1/M1) tumors. There were 45,084 all-cause deaths (23.2%) in the intervention group and 50,336 deaths (23.3%) in the control group respectively (RR 0.97 [95% CI 0.94, 1.01]; p=0.11). Eight deaths in the intervention and seven deaths in the control group were related to a diagnostic biopsy or prostate cancer treatment.CONCLUSIONS AND RELEVANCE A single invitation for PSA screening, compared to standard practice without routine screening, reduced the secondary outcome of prostate cancer deaths at a median follow-up of 15-years. However, the absolute reduction in deaths was small.<br/
Ultraviolet-to-Far Infrared Properties of Lyman Break Galaxies and Luminous Infrared Galaxies at z ~ 1
We present the first large, unbiased sample of Lyman Break Galaxies (LBGs) at
z ~ 1. Far ultraviolet-dropout (1530 A) galaxies in the Chandra Deep Field
South have been selected using GALEX data. This first large sample in the z ~ 1
universe provides us with a high quality reference sample of LBGs. We analyzed
the sample from the UV to the IR using GALEX, SPITZER, ESO and HST data. The
morphology (obtained from GOODS data) of 75 % of our LBGs is consistent with a
disk. The vast majority of LBGs with an IR detection are also Luminous Infrared
Galaxies (LIRGs). As a class, the galaxies not detected at 24 microns are an
order of magnitude fainter relative to the UV compared with those detected
individually, suggesting that there may be two types of behavior within the
sample. For the IR-bright galaxies, there is an apparent upper limit for the UV
dust attenuation and this upper limit is anti-correlated with the observed UV
luminosity. Previous estimates of dust attenuations based on the ultraviolet
slope are compared to new ones based on the FIR/UV ratio (for LBGs detected at
24 microns), which is usually a more reliable estimator. Depending on the
calibration we use to estimate the total IR luminosity, beta-based attenuations
A_{FUV} are larger by 0.2 to 0.6 mag. than the ones estimated from FIR/UV
ratio. Finally, for IR-bright LBGs, median estimated beta-based SFRs are 2-3
times larger than the total SFRs estimated as SFR_{TOT} = SFR_{UV} + SFR_{IR}
while IR-based SFRs provide values below SFR_{TOT} by 15 - 20 %. We use a
stacking method to statistically constrain the 24 microns flux of LBGs non
individually detected. The results suggest that these LBGs do not contain large
amounts of dust.Comment: Accepted for publication in Astronomy and Astrophysic
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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