To assess prostate magnetic resonance imaging (MRI) image quality and compliance with technical standards between centres in the South West region of the UK.
Fifteen imaging sites in the region ...submitted seven consecutive anonymised MRI studies. These were assessed by two experienced radiologists in consensus. Overall, subjective image quality for T2-weighted imaging (T2W), diffusion weighted imaging (DWI), and dynamic contrast enhancement (DCE) was scored on a five-point Likert scale. Five additional quality parameters were also assessed visually, including image noise, motion, artefact, and distortion. The degree of compliance by each site with 21 published technical standards was also assessed.
Ninety-four MRI examinations were reviewed from across all sites (mean 6.3 scans per site, range 5–7). Mean compliance with technical standards was 63% (range 38–86%). Forty-seven percent of sites did not perform DCE. One site used a 3 T scanner. The percentage of patients with overall quality scores of ≥3 (diagnostically acceptable) were 68% for T2W, 81% for DWI, and 60% for both T2W and DWI. Ninety-three percent of the 45 patients who underwent DCE had diagnostically acceptable studies. By scanner age, the percentage of patients with diagnostically acceptable T2W scores was 53% for scanners ≥7 years and 80% when <7 years (p=0.006). Comparing individual sites, the mean overall quality scores were 2.9 (range 2.2–4.2) for T2W, 3.2 (1.8–4.7) for DWI, and 3.4 (2.5–4.7) for DCE.
There is wide variation in compliance with recognised technical standards and image quality across sites. If MRI is to replace biopsy in selected low-risk patients, improvements in image quality may be required.
•There was a large variation in image quality and guideline compliance between sites.•40% of patients had non-diagnostic quality scans.•Scanner age inversely correlated with T2W image quality.•DCE scored highest for image quality, but was only used in 53% of sites.•Image quality needs optimization if MRI is used to rule out cancer or avoid biopsy.
The objective of this study was to compare the relative conspicuity of bone metastases on short-tau inversion recovery (STIR) and diffusion-weighted MRI (DWI) whole-body MR sequences for breast, ...prostate and myeloma malignancies.
44 whole-body MRI scans were reviewed retrospectively (coronal T(1) weighted, STIR and DWI with b=800). On each scan, up to four of the largest bone lesions were identified on T(1) weighting, and the region of interest signal intensity was measured on STIR and DWI, as well as the background signal intensity. The mean lesion signal to background ratio was calculated for each patient and then for each malignancy group.
In prostate cancer patients, the DWI signal/background ratio was greater than that of STIR in 22 out of 24 patients (mean DWI lesion/background ratio 3.91, mean STIR lesion/background ratio 2.31; p=0.0001). In multiple myeloma, the DWI ratio was higher in 6/7 patients (DWI group mean ratio 7.59, STIR group mean ratio 3.7; p=0.0366). In 13 breast cancer patients, mean STIR and DWI signal/background were similar (DWI group mean ratio 4.13, group mean STIR ratio 4.26; p=0.8587).
Bone lesion conspicuity measured by lesion/background signal intensity was higher on DWI b=800 than on STIR in patients with prostate cancer and multiple myeloma. DWI should be used in whole-body MR oncology protocols in these conditions to maximise lesion detection.
Introduction. The aim of this study was to determine the prevalence of burnout, and of associated factors, amongst family doctors (FDs) in European countries. Methodology. A cross-sectional survey of ...FDs was conducted using a custom-designed and validated questionnaire which incorporated the Maslach Burnout Inventory Human Services Survey (MBI-HSS) as well as questions about demographic factors, working experience, health, lifestyle and job satisfaction. MBI-HSS scores were analysed in the three dimensions of emotional exhaustion (EE), depersonalization (DP) and personal accomplishment (PA). Results. Almost 3500 questionnaires were distributed in 12 European countries, and 1393 were returned to give a response rate of 41%. In terms of burnout, 43% of respondents scored high for EE burnout, 35% for DP and 32% for PA, with 12% scoring high burnout in all three dimensions. Just over one-third of doctors did not score high for burnout in any dimension. High burnout was found to be strongly associated with several of the variables under study, especially those relative to respondents’ country of residence and European region, job satisfaction, intention to change job, sick leave utilization, the (ab)use of alcohol, tobacco and psychotropic medication, younger age and male sex. Conclusions. Burnout seems to be a common problem in FDs across Europe and is associated with personal and workload indicators, and especially job satisfaction, intention to change job and the (ab)use of alcohol, tobacco and medication. The study questionnaire appears to be a valid tool to measure burnout in FDs. Recommendations for employment conditions of FDs and future research are made, and suggestions for improving the instrument are listed.
During the 19th century various criticisms of Euclid's geometry emerged and alternative axiom systems were constructed. That of David Hilbert (1, 1899) paid particular attention to the independence ...of the axioms, and it is his insights which have shaped many of the further developments during the 20th century.
We can, from his insights, define an
affine plane
as a set of
points
, with distinguished subsets called lines such that
Axiom 1: Given two distinct points, there is a unique line containing them both.
Axiom 2: Given a line
L
and a point,
p
, not contained in
L
, there is a unique line containing
p
which does not intersect
L
.
Axiom 3: There exist at least three points, not belonging to the same line.
To evaluate the magnetic resonance (MR) imaging appearances of uterine fibroleiomyoma before and after embolization and to determine whether there are preembolization MR imaging characteristics that ...are predictive of a successful outcome.
MR imaging was performed in 18 patients (32 fibroleiomyomas) before and at 2 and 6 months after embolization of the uterine arteries. On each occasion, fibroleiomyoma signal intensity and gadolinium enhancement characteristics were assessed in comparison with those of myometrium on T1-weighted and gadolinium-enhanced images or with those of skeletal muscle on T2-weighted images. Fibroleiomyoma volume was measured by using the ellipsoid formula.
The mean fibroleiomyoma volume before embolization was 340 cm3 (range, 15-1,383 cm3). The mean reduction in fibroleiomyoma volume was 43% at 2 months and 59% at 6 months. Before embolization, high signal intensity on T1-weighted images was predictive of a poor response (P = .008), and high signal intensity on T2-weighted images was predictive of a good response (P = .007). The degree of gadolinium enhancement was not correlated with fibroleiomyoma volume reduction (P = .46).
MR imaging was useful for evaluation of changes in fibroleiomyoma volume after uterine arterial embolization. MR imaging characteristics of fibroleiomyomas before embolization can help predict subsequent response to treatment.
The use of scintillometers to determine sensible and latent heat flux is becoming increasingly common because of their ability to quantify convective fluxes over distances of hundreds of meters to ...several kilometers. The majority of investigations using scintillometry have focused on processes above land surfaces, but here we propose a new methodology for obtaining sensible and latent heat fluxes from a scintillometer deployed over open water. This methodology has been tested by comparison with eddy covariance measurements and through comparison with alternative scintillometer calculation approaches that are commonly used in the literature. The methodology is based on linearization of the Bowen ratio, which is a common assumption in models such as Penman's model and its derivatives. Comparison of latent heat flux estimates from the eddy covariance system and the scintillometer showed excellent agreement across a range of weather conditions and flux rates, giving a high level of confidence in scintillometry‐derived latent heat fluxes. The proposed approach produced better estimates than other scintillometry calculation methods because of the reliance of alternative methods on measurements of water temperature or water body heat storage, which are both notoriously hard to quantify. The proposed methodology requires less instrumentation than alternative scintillometer calculation approaches, and the spatial scales of required measurements are arguably more compatible. In addition to scintillometer measurements of the structure parameter of the refractive index of air, the only measurements required are atmospheric pressure, air temperature, humidity, and wind speed at one height over the water body.
Key Points
A methodology for determining open water fluxes using scintillometry is proposed
Comparison of scintillometry and eddy covariance fluxes shows good performance
Technique builds on that proposed by Vercauteren et al. (2009)
AbstractObjectiveTo investigate the use of repurposed and adjuvant drugs in patients admitted to hospital with covid-19 across three continents.DesignMultinational network cohort ...study.SettingHospital electronic health records from the United States, Spain, and China, and nationwide claims data from South Korea.Participants303 264 patients admitted to hospital with covid-19 from January 2020 to December 2020.Main outcome measuresPrescriptions or dispensations of any drug on or 30 days after the date of hospital admission for covid-19.ResultsOf the 303 264 patients included, 290 131 were from the US, 7599 from South Korea, 5230 from Spain, and 304 from China. 3455 drugs were identified. Common repurposed drugs were hydroxychloroquine (used in from <5 (<2%) patients in China to 2165 (85.1%) in Spain), azithromycin (from 15 (4.9%) in China to 1473 (57.9%) in Spain), combined lopinavir and ritonavir (from 156 (<2%) in the VA-OMOP US to 2,652 (34.9%) in South Korea and 1285 (50.5%) in Spain), and umifenovir (0% in the US, South Korea, and Spain and 238 (78.3%) in China). Use of adjunctive drugs varied greatly, with the five most used treatments being enoxaparin, fluoroquinolones, ceftriaxone, vitamin D, and corticosteroids. Hydroxychloroquine use increased rapidly from March to April 2020 but declined steeply in May to June and remained low for the rest of the year. The use of dexamethasone and corticosteroids increased steadily during 2020.ConclusionsMultiple drugs were used in the first few months of the covid-19 pandemic, with substantial geographical and temporal variation. Hydroxychloroquine, azithromycin, lopinavir-ritonavir, and umifenovir (in China only) were the most prescribed repurposed drugs. Antithrombotics, antibiotics, H2 receptor antagonists, and corticosteroids were often used as adjunctive treatments. Research is needed on the comparative risk and benefit of these treatments in the management of covid-19.
Abstract Background Thyrotoxic periodic paralysis is rare in Caucasian populations, but affects approximately 2% of East Asians with thyrotoxicosis (13% of males, 0.17% of females). The presentation ...is characterized by abrupt-onset hypokalemia and profound proximal muscular weakness, and commonly occurs after carbohydrate loading or exercise. Objectives To raise awareness of this condition through the description of a typical case of thyrotoxic periodic paralysis; to remind readers that, despite intravascular hypokalemia, total body potassium is normal and that correction must be done with caution; to highlight the differences in treatment compared to familial hypokalemic periodic paralysis. Case Report We describe the presentation of a 36-year-old Filipino man with a background history of Graves disease. Over-administration of intravenous potassium was narrowly averted in this case. Conclusion It may be important to check thyroid function in patients presenting with acute paralysis, especially those of Asian origin. In patients with thyrotoxic periodic paralysis, administration of potassium, with cardiac monitoring and a total dose of <50 mmol, limits the dysrhythmia risk. Patients are likely to benefit from the prescription of non-selective beta-blockers until they become euthyroid. In contrast to familial periodic paralysis, regular oral potassium supplementation is ineffective in thyrotoxic periodic paralysis, and acetazolamide precipitates, rather than prevents, attacks.
Identification of rheumatoid arthritis (RA) patients at high risk of adverse health outcomes remains a major challenge. We aimed to develop and validate prediction models for a variety of adverse ...health outcomes in RA patients initiating first-line methotrexate (MTX) monotherapy.
Data from 15 claims and electronic health record databases across 9 countries were used. Models were developed and internally validated on Optum® De-identified Clinformatics® Data Mart Database using L1-regularized logistic regression to estimate the risk of adverse health outcomes within 3 months (leukopenia, pancytopenia, infection), 2 years (myocardial infarction (MI) and stroke), and 5 years (cancers colorectal, breast, uterine after treatment initiation. Candidate predictors included demographic variables and past medical history. Models were externally validated on all other databases. Performance was assessed using the area under the receiver operator characteristic curve (AUC) and calibration plots.
Models were developed and internally validated on 21,547 RA patients and externally validated on 131,928 RA patients. Models for serious infection (AUC: internal 0.74, external ranging from 0.62 to 0.83), MI (AUC: internal 0.76, external ranging from 0.56 to 0.82), and stroke (AUC: internal 0.77, external ranging from 0.63 to 0.95), showed good discrimination and adequate calibration. Models for the other outcomes showed modest internal discrimination (AUC < 0.65) and were not externally validated.
We developed and validated prediction models for a variety of adverse health outcomes in RA patients initiating first-line MTX monotherapy. Final models for serious infection, MI, and stroke demonstrated good performance across multiple databases and can be studied for clinical use.
This activity under the European Health Data & Evidence Network (EHDEN) has received funding from the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 806968. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation programme and EFPIA.
Bile acid biosynthesis is regulated by both feed-forward and feedback mechanisms involving a cascade of nuclear hormone receptors. Feed-forward regulation of the rate limiting enzyme in bile acid ...biosynthesis is provided by oxysterols through liver-X-receptor α (NR1H3), while feedback regulation is provided by bile acids through farnesoid-X-receptor (FXR) (NR1H4). The Syrian golden hamster provides a useful model for studying lipid metabolism. The hamster metabolizes and transports dietary cholesterol in a similar manner to humans, with the resulting lipid profile being more similar to the human profile than that of other rodent models. Cloning of
Fxr from Syrian golden hamster revealed four hamster
Fxr splice variants that altered the N-terminal activation domain or the hinge region between the DNA and ligand binding domains. Human genomic sequence and data from hamster Fxr were used to identify and clone a novel human
FXR isoform resulting from the use of an alternative promoter. RNA expression analysis indicates that the two human
FXR isoforms are differentially expressed in developmental and tissue-specific patterns and are likely to provide a mechanism for cell-specific FXR-dependent transcriptional activity.
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