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Abstract Purpose A 2D image navigator (iNAV) based 3D whole-heart sequence has been used to perform MRI and PET non-rigid respiratory motion correction for hybrid PET/MRI. However, only the PET data acquired during the acquisition of the 3D whole-heart MRI is corrected for respiratory motion. This study introduces and evaluates an MRI-based respiratory motion correction method of the complete PET data. Methods Twelve oncology patients scheduled for an additional cardiac 18F-Fluorodeoxyglucose (18F-FDG) PET/MRI and 15 patients with coronary artery disease (CAD) scheduled for cardiac 18F-Choline (18F-FCH) PET/MRI were included. A 2D iNAV recorded the respiratory motion of the myocardium during the 3D whole-heart coronary MR angiography (CMRA) acquisition (~ 10 min). A respiratory belt was used to record the respiratory motion throughout the entire PET/MRI examination (~ 30–90 min). The simultaneously acquired iNAV and respiratory belt signal were used to divide the acquired PET data into 4 bins. The binning was then extended for the complete respiratory belt signal. Data acquired at each bin was reconstructed and combined using iNAV-based motion fields to create a respiratory motion-corrected PET image. Motion-corrected (MC) and non-motion-corrected (NMC) datasets were compared. Gating was also performed to correct cardiac motion. The SUVmax and TBRmax values were calculated for the myocardial wall or a vulnerable coronary plaque for the 18F-FDG and 18F-FCH datasets, respectively. Results A pair-wise comparison showed that the SUVmax and TBRmax values of the motion corrected (MC) datasets were significantly higher than those for the non-motion-corrected (NMC) datasets (8.2 ± 1.0 vs 7.5 ± 1.0, p

Hybrid PET-MRI systems are being used more frequently. One of the drawbacks of PET-MRI imaging is its inferiority in detecting lung nodules, so it is often combined with a computed tomography (CT) of the chest. However, chest CT often detects additional, indeterminate lung nodules. The objective of this study was to assess the sensitivity of detecting metastatic versus indeterminate nodules with PET-MRI compared to chest CT. A total of 328 patients were included. All patients had a PET/MRI whole-body scan for (re)staging of cancer combined with an unenhanced chest CT performed at our center between 2014 and 2020. Patients had at least a two-year follow-up. Six percent of the patients had lung metastases at initial staging. The sensitivity and specificity of PET-MRI for detecting lung metastases were 85% and 100%, respectively. The incidence of indeterminate lung nodules on chest CT was 30%. The sensitivity of PET-MRI to detect indeterminate lung nodules was poor (23.0%). The average size of the indeterminate lung nodules detected on PET-MRI was 7 ± 4 mm, and the missed indeterminate nodules on PET-MRI were 4 ± 1 mm (p < 0.001). The detection of metastatic lung nodules is fairly good with PET-MRI, whereas the sensitivity of PET-MRI for detecting indeterminate lung nodules is size-dependent. This may be an advantage, limiting unnecessary follow-up of small, indeterminate lung nodules while adequately detecting metastases.

Because of the improvement-oriented nature of peer-feedback activities, students have to deal with errors (e.g., spelling and argumentation errors) when providing and processing peer-feedback on writing assignments. Despite the central role of errors in feedback activities, it is uncertain how students deal with errors and whether the dealing with errors is affected by interpersonal perceptions. Therefore, this study explores (1) whether cognitive sub-phases are distinguishable during the process of dealing with errors and (2) the extent to which dealing with errors is affected by interpersonal perceptions. Six dyads of Dutch 11th grade students provided and processed peer-feedback on argumentative texts while thinking-aloud, and they reflected on the processes in a post-interview. The think-aloud utterances and interviews were analyzed with a mixed-methods design, using quantitative content analyses, and qualitative thematic analyses. The dealing with errors during peer-feedback provision displayed two patterns: error identification either occurred simultaneously with the decoding and often any evaluation-related thoughts lacked, or error-identification occurred as a result of an interpreting/evaluating phase. Also during peer-feedback processing, two main patterns were observable: students either knew immediately whether they agreed with feedback, or they first had to study the feedback more thoroughly. Additionally, interpersonal perceptions seemed to affect most students implicitly during feedback provision, and most students explicitly during feedback processing. As such, this study provides empirical evidence for the existence of cognitive sub-phases in the process of dealing with errors during peer-feedback activities, and portrays how these activities may be affected by interpersonal perceptions.

Abstract Background Vagus nerve activation impacts inflammation. Therefore, we hypothesized that vagal nerve stimulation (VNS) influenced arterial wall inflammation as measured by 18F-FDG uptake. Results Ten patients with left-sided VNS for refractory epilepsy were studied during stimulation (VNS-on) and in the hours after stimulation was switched off (VNS-off). In nine patients, 18F-FDG uptake was measured in the right carotid artery, aorta, bone marrow, spleen, and adipose tissue. Target-to-background ratios (TBRs) were calculated to normalize the respective standardized uptake values (SUVs) for venous blood pool activity. Median values are shown with interquartile range and compared using the Wilcoxon signed-rank test. Arterial SUVs tended to be higher during VNS-off than VNS-on [SUVmax all vessels 1.8 (1.5–2.2) vs. 1.7 (1.2–2.0), p = 0.051]. However, a larger difference was found for the venous blood pool at this time point, reaching statistical significance in the vena cava superior [meanSUVmean 1.3 (1.1–1.4) vs. 1.0 (0.8–1.1); p = 0.011], resulting in non-significant lower arterial TBRs during VNS-off than VNS-on. Differences in the remaining tissues were not significant. Insulin levels increased after VNS was switched off [55.0 pmol/L (45.9–96.8) vs. 48.1 pmol/L (36.9–61.8); p = 0.047]. The concurrent increase in glucose levels was not statistically significant [4.8 mmol/L (4.7–5.3) vs. 4.6 mmol/L (4.5–5.2); p = 0.075]. Conclusions Short-term discontinuation of VNS did not show a consistent change in arterial wall 18F-FDG-uptake. However, VNS did alter insulin and 18F-FDG blood levels, possibly as a result of sympathetic activation.

This research examined the preference for identity-first language (IFL) versus person-first language (PFL) among 215 respondents (M[subscript age] = 30.24 years, SD = 9.92) from the Dutch autism community. We found that a stronger identification with the autism community and a later age of diagnosis predicted a stronger IFL preference and a weaker PFL preference. Both effects were mediated by the perceived consequences (justice to identity, prejudice reduction) of PFL. Participants' own explanations were in line with these statistical analyses but also provided nuance to the IFL-PFL debate. Our results are consistent with the Social Identity Approach (Reicher et al., 2010) and Identity Uncertainty Theory (Hogg, 2007) and demonstrate the value of a social psychological approach to study disability language preferences.

Carotid radiofrequency coils inside a PET/MRI system can result in PET quantification errors. We compared the performance of a dedicated PET/MRI carotid coil against a coil for MRI-only use. An 18F-fluorodeoxyglucose (18F-FDG) phantom was scanned without and with an MRI-only coil and with the PET/MRI coil. The decay-corrected normalized activity was compared for the different coil configurations. Eighteen patients were scanned with the three coil configurations. The maximal standardized uptake values (SUVmax) and signal-to-noise ratios (SNR) were calculated. Repeated measures ANOVA was performed to assess the differences in SUVmax and SNR between the coil configurations. In the phantom study, the PET/MRI coil demonstrated a slight decrease (max values for both no surface coil (3.59 ± 0.15) and PET/MRI coil (3.54 ± 0.15) were significantly higher (p = 0.03 and p = 0.04, respectively) as compared to the MRI-only coil (3.28 ± 0.16). No significant difference was observed between PET/MRI and no surface coil (p = 1.0). The SNR values for both PET/MRI (7.31 ± 0.44) and MRI-only (7.62 ± 0.42) configurations demonstrated significantly higher (p < 0.001) SNR values as compared to the no surface coil (3.78 ± 0.22), while no significant difference was observed in SNR between the PET/MRI and MRI-only coil (p = 1.0). This study demonstrated that the PET/MRI coil can be used for PET imaging without requiring attenuation correction while acquiring high-resolution MR images.

Gliomas are the most frequent primary tumors of the brain. They can be divided into grade II-IV astrocytomas and grade II-III oligodendrogliomas, based on their histomolecular profile. The prognosis and treatment is highly dependent on grade and well-identified prognostic and/or predictive molecular markers. Multi-parametric MRI, including diffusion weighted imaging, perfusion, and MR spectroscopy, showed increasing value in the non-invasive characterization of specific molecular subsets of gliomas. Radiolabeled amino-acid analogues, such as 18F-FET, have also been proven valuable in glioma imaging. These tracers not only contribute in the diagnostic process by detecting areas of dedifferentiation in diffuse gliomas, but this technique is also valuable in the follow-up of gliomas, as it can differentiate pseudo-progression from real tumor progression. Since multi-parametric MRI and 18F-FET PET are complementary imaging techniques, there may be a synergistic role for PET-MRI imaging in the neuro-oncological imaging of primary brain tumors. This could be of value for both primary staging, as well as during treatment and follow-up.

Background: This study aimed to identify plasma lipoproteins and small metabolites associated with high risk of malnutrition during intensive care unit (ICU) stay in patients with severe injuries. Methods: This observational prospective exploratory study was conducted at two level-1 trauma centers in the Netherlands. Adult patients (aged ≥18 years) who were admitted to the ICU for more than 48 h between July 2018 and April 2022 owing to severe injuries (polytrauma, as defined by Injury Severity Scores of ≥16) caused by blunt trauma were eligible for inclusion. Partial least squares discriminant analysis was used to analyze the relationship of 112 lipoprotein-related components and 23 small metabolites with the risk of malnutrition (modified Nutrition Risk in Critically Ill score). Malnutrition was diagnosed based on Subjective Global Assessment scores. The relationship of lipoprotein properties and small metabolite concentrations with malnutrition (during ICU admission) was evaluated using mixed effects logistic regression. Results: Overall, 51 patients were included. Lower (very) low-density lipoprotein ([V]LDL) (free) cholesterol and phospholipid levels, low particle number, and higher levels of LDL triglycerides were associated with a higher risk of malnutrition (variable importance in projection [VIP] value >1.5). Low levels of most (V)LDL and intermediate-density lipoprotein subfractions and high levels of high-density lipoprotein Apo-A1 were associated with the diagnosis of malnutrition (VIP value >1.5). Increased levels of dimethyl sulfone, trimethylamine N-oxide, creatinine, N, N-dimethylglycine, and pyruvic acid and decreased levels of creatine, methionine, and acetoacetic acid were also indicative of malnutrition (VIP value >1.5). Overall, 14 lipoproteins and 1 small metabolite were significantly associated with a high risk of malnutrition during ICU admission (P

Abstract Cryptococcal meningitis is a high-mortality infection. Adding 5-fluorocytosine (5-FC) to its treatment improves outcomes, but resistance to 5-FC presents a significant challenge. We conducted whole-genome sequencing on seven C. neoformans isolates with varying 5-FC susceptibility, along with proteomic and in silico analyses. Our findings indicate that mutations in genes of the pyrimidine salvage pathway are responsible for 5-FC resistance. Specifically, we identified an E64G missense mutation in the FUR1 gene, a large deletion in the FCY1 gene, and a point mutation in FCY1 leading to a truncated protein. The proteomic data indicated that these mutations resulted in the absence or reduction of crucial enzymes in resistant isolates. Genetic transformations confirmed the association between these mutations and 5-FC resistance. Resistance to 5-FC can develop during treatment and is closely tied to mutations in key metabolic enzymes. Understanding in vivo resistance development is crucial for combating resistance and enhancing patient outcomes.

Abstract Background Self-rated physical health (SRPH) is known as an important predictor of mortality. Previous studies mostly used baseline values of self-rated health to predict long-term mortality. The effect of change in self-rated physical health on mortality during the course of aging has rarely been researched. The present study aimed to determine SRPH over time in women and men of an aging population, assess whether and how change in SRPH affects mortality while adjusting for known determinants of mortality, and test effect modification by sex on the relation between course of SRPH and mortality. Methods Data of N = 12,423 respondents of the 5-year follow-up of the Gutenberg Health Study (GHS) with participation at the baseline assessment were analysed. All-cause mortality from 5-year follow-up onwards was defined as the primary outcome. SRPH was assessed by a single item. Cox proportional hazards models with adjustment for age, sex, socio-economic status and physical diseases were fitted to assess the predictive power of baseline score and course of SRPH. Additionally, effect modification by sex was assessed. Results During a median follow-up period of 7.3 years (quartiles 6.0-8.5 years), 618 (5%) participants died. Overall, 70.9% of the participants indicated good or very good SRPH at baseline (T1) and follow-up (T2), 6.9% rated their SRPH as not so good at T1 and T2, and 0.6% reported bad SRPH at T1 and T2. An improvement of SRPH was indicated by 9.6% and 12.0% indicated deterioration of their SRPH. Change in SRPH added substantial predictive information to the Cox proportional hazards models, when adjusting for relevant covariates. In men, deterioration and constantly bad SRPH were associated with the strongest increase in risk of mortality by 87%, resp. 228%. While improvements increased mortality risk in men (67%), women with an improved SRPH had a lower risk (57%). Conclusion A sizeable subgroup of aging participants reported deterioration of SRPH over five years. The association between change of SRPH and mortality is modified by sex. Deterioration of SRPH predicts mortality over baseline-assessment even when adjusted for relevant covariates. SRPH should be assessed regularly as part of an older individual’s health evaluation. Deterioration, constantly bad and improved SRPH should be taken seriously as unfavorable prognostic indicators, the latter only in men.

Benign tumours of the bone are not cancerous and would not metastasise to other regions of the body. However, they can occur in any part of the skeleton, and can still be dangerous as they may grow and compress healthy bone tissue. There are several types of benign tumours that can be classified by the type of matrix that the tumour cells produce; such as bone, cartilage, fibrous tissue, fat or blood vessel. Overall, 8 different types can be distinguished: osteochondroma, osteoma, osteoid osteoma, osteoblastoma, giant cell tumour, aneurysmal bone cyst, fibrous dysplasia and enchondroma. The incidence of benign bone tumours varies depending on the type. However, they most commonly arise in people less than 30 years old, often triggered by the hormones that stimulate normal growth. The most common type is osteochondroma. This review discusses the different types of common benign tumours of the bone based on information accumulated from published literature.