Background and purpose: To develop a method of using a multileaf collimator (MLC) to deliver intensity modulated radiotherapy (IMRT) for tangential breast fields, using an MLC to deliver a set of ...multiple static fields (MSFs).
Materials and methods: An electronic portal imaging device (EPID) is used to obtain thickness maps of medial and lateral tangential breast fields. From these IMRT deliveries are designed to minimize the volume of breast above 105% of prescribed dose. The deliveries are universally-wedged beams augmented with a set of low dose shaped irradiations. Dosimetric and planning QA of this method has been compared with the standard, wedged treatment and the corresponding treatment using physical compensators. Several options for delivering the MSF treatment are presented.
Results: The MSF technique was found to be superior to the standard technique (
P value=0.002) and comparable with the compensated technique. Both IMRT methods reduced the volume of breast above 105% dose from a mean value of 12.0% of the total breast volume to ∼2.8% of the total breast volume.
Conclusions: This MSF method may be used to reduce the high dose volume in tangential breast irradiation significantly. This may have consequences for long-term side effects, particularly cosmesis.
Background
A low electrocardiogram (ECG) lead one ratio (LOR) of the maximum positive/negative QRS amplitudes is associated with lower left ventricular ejection fraction (LVEF) and worse outcomes in ...left bundle branch block (LBBB); however, the impact of LOR on cardiac resynchronization therapy (CRT) outcomes is unknown. We compared clinical outcomes and echocardiographic changes after CRT implantation by LOR.
Methods
Consecutive CRT‐defibrillator recipients with LBBB implanted between 2006 and 2015 at Duke University Medical Center were included (N = 496). Time to heart transplant, left ventricular assist device (LVAD) implantation, or death was compared among patients with LOR <12 vs ≥12 using Cox‐proportional hazard models. Changes in LVEF and LV volumes after CRT were compared by LOR.
Results
Baseline ECG LOR <12 was associated with an adjusted hazard ratio (HR) of 1.69 (95% CI: 1.12‐2.40, P = .01) for heart transplant, LVAD, or death. Patients with LOR <12 had less reduction of LV end diastolic volume (ΔLVEDV −4 ± 21 vs −13 ± 23%, P = .04) and LV end systolic volume (ΔLVESV −9 ± 27 vs −22 ± 26%, P = .03) after CRT. In patients with QRS duration (QRSd) ≥150 ms, LOR <12 was associated with an adjusted HR of 2.01 (95% CI 1.21‐3.35, P = .008) for heart transplant, LVAD, or death, compared with LOR ≥12.
Conclusions
Baseline ECG LOR <12 portends worse outcomes after CRT implantation in patients with LBBB, specifically among those with QRSd ≥150 ms. This ECG ratio may identify patients with a class I indication for CRT implantation at high risk for poor postimplantation outcomes.
Background and Aims The optimal timing of endoscopy in patients with peptic ulcer bleeding (PUB) remains unclear. The aim of this study was to examine the association between timing of endoscopy and ...mortality in PUB. Methods In a nationwide cohort study based on a database of consecutive patients admitted to the hospital with PUB in Denmark, patients were stratified according to the presence of hemodynamic instability at presentation and American Society of Anesthesiologists (ASA) score. Using descriptive statistics and logistic regression analyses, we identified optimal time frames for endoscopy and analyzed the association between timing of endoscopy and in-hospital mortality after adjusting for confounding factors. Results In total, 12,601 patients were included. We did not find any universal association between timing of endoscopy and mortality in hemodynamically stable patients with an ASA score of 1 to 2. In hemodynamically stable patients with an ASA score of 3 to 5, endoscopy 12 to 36 hours after admission to the hospital was associated with lower in-hospital mortality (OR, .48; 95% CI, .34-.67) compared with endoscopy outside this time frame. In patients with hemodynamic instability, endoscopy 6 to 24 hours after admission to the hospital was associated with lower in-hospital mortality (OR, .73; 95% CI, .54-.98) compared with endoscopy outside this time frame. Conclusions Timing of endoscopy is associated with mortality in patients with PUB and an ASA score of 3 to 5 or hemodynamic instability. Our findings suggest that in these patients, a period of time to optimize resuscitation and manage comorbidities before endoscopy may improve outcome.
Several observables sensitive to the fragmentation of $\textit{b}$ quarks into $\textit{b}$ hadrons are measured using 36 fb-1 of $\sqrt{s}$ = 13 TeV proton-proton collision data collected with the ...ATLAS detector at the LHC. Jets containing b hadrons are obtained from a sample of dileptonic $t\bar{t}$ events, and the associated set of charged-particle tracks is separated into those from the primary $\textit{pp}$ interaction vertex and those from the displaced b-decay secondary vertex. This division is used to construct observables that characterize the longitudinal and transverse momentum distributions of the $\textit{b}$ hadron within the jet. The measurements have been corrected for detector effects and provide a test of heavy-quark-fragmentation modeling at the LHC in a system where the top-quark decay products are color connected to the proton beam remnants. The unfolded distributions are compared with the predictions of several modern Monte Carlo parton-shower generators and generator tunes, and a wide range of agreement with the data is observed, with $\textit{p}$ values varying from 5 × 10-4 to 0.98. These measurements complement similar measurements from $e^+e^-$ collider experiments in which the $\textit{b}$ quarks originate from a color singlet $Z/γ^{\ast}$.
Despite established clinical associations among major depression (MD), alcohol dependence (AD), and alcohol consumption (AC), the nature of the causal relationship between them is not completely ...understood. We leveraged genome-wide data from the Psychiatric Genomics Consortium (PGC) and UK Biobank to test for the presence of shared genetic mechanisms and causal relationships among MD, AD, and AC.
Linkage disequilibrium score regression and Mendelian randomization (MR) were performed using genome-wide data from the PGC (MD: 135 458 cases and 344 901 controls; AD: 10 206 cases and 28 480 controls) and UK Biobank (AC-frequency: 438 308 individuals; AC-quantity: 307 098 individuals).
Positive genetic correlation was observed between MD and AD (rgMD-AD = + 0.47, P = 6.6 × 10-10). AC-quantity showed positive genetic correlation with both AD (rgAD-AC quantity = + 0.75, P = 1.8 × 10-14) and MD (rgMD-AC quantity = + 0.14, P = 2.9 × 10-7), while there was negative correlation of AC-frequency with MD (rgMD-AC frequency = -0.17, P = 1.5 × 10-10) and a non-significant result with AD. MR analyses confirmed the presence of pleiotropy among these four traits. However, the MD-AD results reflect a mediated-pleiotropy mechanism (i.e. causal relationship) with an effect of MD on AD (beta = 0.28, P = 1.29 × 10-6). There was no evidence for reverse causation.
This study supports a causal role for genetic liability of MD on AD based on genetic datasets including thousands of individuals. Understanding mechanisms underlying MD-AD comorbidity addresses important public health concerns and has the potential to facilitate prevention and intervention efforts.
Extensive experimental data from high-energy nucleus-nucleus collisions were recorded using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The comprehensive set of measurements ...from the first three years of RHIC operation includes charged particle multiplicities, transverse energy, yield ratios and spectra of identified hadrons in a wide range of transverse momenta (
p
T
), elliptic flow, two-particle correlations, nonstatistical fluctuations, and suppression of particle production at high
p
T
. The results are examined with an emphasis on implications for the formation of a new state of dense matter. We find that the state of matter created at RHIC cannot be described in terms of ordinary color neutral hadrons.
Eight Holstein cows (average = 52 DIM) were used in a replicated Latin square design (28-d periods) to determine the effects of source and amount of dietary energy on hepatic lipid metabolism. Diets ...were 1) low concentrate without supplemental fat (1.6 Mcal of NEL/kg), 2) low concentrate with supplemental fat (1.7 Mcal/kg), 3) high concentrate without supplemental fat (1.7 Mcal/kg), and 4) high concentrate with supplemental fat (1.8 Mcal/kg). Intakes of DM and digestible energy were greatest for diets 2 and 3. Milk production, efficiency, and milk CP production were not different among diets. Milk fat percentage and production were increased by supplemental fat and decreased by high concentrate. Contents of CP, true protein, and casein in milk were decreased by supplemental fat and increased by high concentrate. Digestibility of fatty acids was decreased by either supplemental fat or high concentrate. Concentrations of NEFA and somatotropin in plasma were increased, d and concentration of IGF-I was decreased, by supplemental fat; NEFA, BHBA, and IGF-I were decreased by high concentrate. In vitro rates of peroxisomal beta-oxidation and esterification of palmitate and concentrations of total lipid and triglycerides in liver were not different among diets, but glycogen content was increased by high concentrate. The rate of total beta-oxidation of palmitate in liver slices tended to be increased by supplemental fat; total metabolism of it palmitate was increased by supplemental fat and tended to be increased by high concentrate. Supplemental fat may affect hepatic lipid metabolism in dairy cows; effects of dietary fat during the periparturient period deserve investigation
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