A comparison of two systems of patient immobilization for prostate radiotherapy

2013-2014 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Carer subjective burden after first-episode psychosis: Types and predictors. A multilevel statistical approach

Background: Carer burden at first-episode psychosis is common and adds to the multiple other psychiatric and psychological problems that beset new carers; yet, knowledge of the factors that predict carer burden is limited. Aim: This study sought to investigate the types and predictors of carer burden at first-episode psychosis in the largest, most ethnically diverse and comprehensively characterised sample to date. Method: This study involved a cross-sectional survey of carers of people with first-episode psychosis presenting to Harrow and Hillingdon Early Intervention in Psychosis service between 2011 and 2017. Carers completed self-report measures assessing their illness beliefs, coping styles and caregiving experiences (i.e. burden). Thirty carer and patient sociodemographic and clinical factors were also collected. Mixed effects linear regression modelling was conducted to account for clustering of carers by patient, with carer burden (and its 8 subtypes) investigated as dependent variables. Results: The sample included data on 254 carers (aged 18–74 years) and 198 patients (aged 14–36 years). Regression modelling identified 35 significant predictors of carer burden and its subtypes at first-episode psychosis. Higher total burden was independently predicted by perceiving greater negative consequences of the illness for the patient (B = .014, p < .001, 95% CI: [.010–.018]) and the carer (B = .008, p = .002, 95% CI: [.003–.013]), and engaging in avoidant-focussed coping (B = .010, p = .006, 95% CI: [.003–.016]). Lower burden was independently predicted by patients being in a relationship (B = −.075, p = .047, 95% CI: [−.149 to −.001]). Predictors of the eight burden subtypes (difficult behaviours, negative symptoms, stigma, problems with services, effects on family, dependency, loss and need to backup) are also included in the article. Conclusion: Findings can be used to inform the identification of carers ‘at-risk’ of experiencing burden and highlight potential targets for theraputic intervention to lower carer buden

Compensated right ventricular function of the onset of pulmonary hypertension in a rat model depends on chamber remodeling and contractile augmentation.

Right-ventricular function is a good indicator of pulmonary arterial hypertension (PAH) prognosis; however, how the right ventricle (RV) adapts to the pressure overload is not well understood. Here, we aimed at characterizing the time course of RV early remodeling and discriminate the contribution of ventricular geometric remodeling and intrinsic changes in myocardial mechanical properties in a monocrotaline (MCT) animal model. In a longitudinal study of PAH, ventricular morphology and function were assessed weekly during the first four weeks after MCT exposure. Using invasive measurements of RV pressure and volume, heart performance was evaluated at end of systole and diastole to quantify contractility (end-systolic elastance) and chamber stiffness (end-diastolic elastance). To distinguish between morphological and intrinsic mechanisms, a computational model of the RV was developed and used to determine the level of prediction when accounting for wall masses and unloaded volume measurements changes. By four weeks, mean pulmonary arterial pressure and elastance rose significantly. RV pressures rose significantly after the second week accompanied by significant RV hypertrophy, but RV stroke volume and cardiac output were maintained. The model analysis suggested that, after two weeks, this compensation was only possible due to a significant increase in the intrinsic inotropy of RV myocardium. We conclude that this MCT-PAH rat is a model of RV compensation during the first month after treatment, where geometric remodeling on EDPVR and increased myocardial contractility on ESPVR are the major mechanisms by which stroke volume is preserved in the setting of elevated pulmonary arterial pressure. The mediators of this compensation might themselves promote longer-term adverse remodeling and decompensation in this animal model

Persistent isolated impairment of gas transfer following COVID-19 pneumonitis relates to perfusion defects on dual-energy computed tomography

Breathlessness is common in patients after COVID-19 [1]. Patients may have an isolated impairment of gas transfer (diffusion of the lung for carbon monoxide, DLCO) at lung function testing, often without obvious interstitial lung disease or classical pulmonary emboli (PE) on imaging. Iodine maps from post-COVID patients undergoing dual energy computed tomography (DECT) demonstrate hypoenhancement in areas of normal lung parenchyma [2] (figure 1). We hypothesized that in breathless patients recovering from COVID-19, low DLCO would correlate with a CT marker of lung perfusion, measured using DECT-derived iodine enhancement, including in patients where parenchymal disease was absent. As an even more specific indicator for the pulmonary vascular compartment, we hypothesized that KCO (DLCO corrected for alveolar volume) would even better correlate with DECT perfusion, and more so than forced vital capacity (FVC) and CT measures of interstitial lung involvement

The sudden change phenomenon of quantum discord

Even if the parameters determining a system's state are varied smoothly, the behavior of quantum correlations alike to quantum discord, and of its classical counterparts, can be very peculiar, with the appearance of non-analyticities in its rate of change. Here we review this sudden change phenomenon (SCP) discussing some important points related to it: Its uncovering, interpretations, and experimental verifications, its use in the context of the emergence of the pointer basis in a quantum measurement process, its appearance and universality under Markovian and non-Markovian dynamics, its theoretical and experimental investigation in some other physical scenarios, and the related phenomenon of double sudden change of trace distance discord. Several open questions are identified, and we envisage that in answering them we will gain significant further insight about the relation between the SCP and the symmetry-geometric aspects of the quantum state space.Comment: Lectures on General Quantum Correlations and their Applications, F. F. Fanchini, D. O. Soares Pinto, and G. Adesso (Eds.), Springer (2017), pp 309-33

Nearly all Massive Quiescent Disk Galaxies Have a Surprisingly Large Atomic Gas Reservoir

The massive galaxy population above the characteristic Schechter mass M*~10^10.6 Msun contributes to about half of the total stellar mass in the local Universe. These massive galaxies usually reside in hot dark matter haloes above the critical shock-heating mass ~10^12 Msun, where the external cold gas supply to these galaxies is expected to be suppressed. When galaxies run out of their cold gas reservoir, they become dead and quiescent. Therefore, massive quiescent galaxies living in hot haloes are commonly believed to be gas-poor. Based on the data from SDSS, ALFALFA, GASS and COLD GASS surveys, here we show that the vast majority of the massive, quiescent, central disk galaxies in the nearby Universe have a remarkably large amount of cold atomic hydrogen gas, surprisingly similar to star-forming galaxies. Both star-forming and quiescent disk galaxies show identical symmetric double-horn HI spectra, indicating similar regularly rotating HI disks. Relative to their star-forming counterparts, massive quiescent central disk galaxies are quenched because of their significantly reduced molecular gas content, lower dust content, and lower star formation efficiency. Our findings reveal a new picture, which clearly demonstrates the detailed star-formation quenching process in massive galaxies and provides a stringent constraint on the physical mechanism of quenching

Consumer perceptions of co-branding alliances: Organizational dissimilarity signals and brand fit

This study explores how consumers evaluate co-branding alliances between dissimilar partner firms. Customers are well aware that different firms are behind a co-branded product and observe the partner firms’ characteristics. Drawing on signaling theory, we assert that consumers use organizational characteristics as signals in their assessment of brand fit and for their purchasing decisions. Some organizational signals are beyond the control of the co-branding partners or at least they cannot alter them on short notice. We use a quasi-experimental design and test how co-branding partner dissimilarity affects brand fit perception. The results show that co-branding partner dissimilarity in terms of firm size, industry scope, and country-of-origin image negatively affects brand fit perception. Firm age dissimilarity does not exert significant influence. Because brand fit generally fosters a benevolent consumer attitude towards a co-branding alliance, the findings suggest that high partner dissimilarity may reduce overall co-branding alliance performance

Metabolic alteration of urinary steroids in pre- and post-menopausal women, and men with papillary thyroid carcinoma

<p>Abstract</p> <p>Background</p> <p>To evaluate the metabolic changes in urinary steroids in pre- and post-menopausal women and men with papillary thyroid carcinoma (PTC).</p> <p>Methods</p> <p>Quantitative steroid profiling combined with gas chromatography-mass spectrometry was used to measure the urinary concentrations of 84 steroids in both pre- (n = 21, age: 36.95 ± 7.19 yr) and post-menopausal female (n = 19, age: 52.79 ± 7.66 yr), and male (n = 16, age: 41.88 ± 8.48 yr) patients with PTC. After comparing the quantitative data of the patients with their corresponding controls (pre-menopause women: n = 24, age: 33.21 ± 10.48 yr, post-menopause women: n = 16, age: 49.67 ± 8.94 yr, male: n = 20, age: 42.75 ± 4.22 yr), the levels of steroids in the patients were normalized to the mean concentration of the controls to exclude gender and menopausal variations.</p> <p>Results</p> <p>Many urinary steroids were up-regulated in all PTC patients compared to the controls. Among them, the levels of three active androgens, androstenedione, androstenediol and 16α-hydroxy DHEA, were significantly higher in the pre-menopausal women and men with PTC. The corticoid levels were increased slightly in the PTC men, while progestins were not altered in the post-menopausal PTC women. Estrogens were up-regulated in all PTC patients but 2-hydroxyestrone and 2-hydroxy-17β-estradiol were remarkably changed in both pre-menopausal women and men with PTC. For both menopausal and gender differences, the 2-hydroxylation, 4-hydroxylation, 2-methoxylation, and 4-methoxylation of estrogens and 16α-hydroxylation of DHEA were differentiated between pre- and post-menopausal PTC women (<it>P </it>< 0.001). In particular, the metabolic ratio of 2-hydroxyestrone to 2-hydroxy-17β-estradiol, which could reveal the enzyme activity of 17β-hydroxysteroid dehydrogenase, showed gender differences in PTC patients (<it>P </it>< 1 × 10^-7).</p> <p>Conclusions</p> <p>These results are expected be helpful for better understanding the pathogenic differences in PTC according to gender and menopausal conditions.</p