quantitative imaging
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BACKGROUND: Modafinil is primarily used to treat narcolepsy but is also used as an off-label cognitive enhancer. Functional magnetic resonance imaging studies indicate that modafinil modulates the connectivity of neocortical networks primarily involved in attention and executive functions. However, much less is known about the drug's effects on subcortical structures. Following preliminary findings, we evaluated modafinil's activity on the connectivity of distinct cerebellar regions with the neocortex. We assessed the spatial relationship of these effects with the expression of neurotransmitter receptors/transporters. METHODS: Patterns of resting-state functional magnetic resonance imaging connectivity were estimated in 50 participants from scans acquired pre- and postadministration of a single (100 mg) dose of modafinil (n = 25) or placebo (n = 25). Using specific cerebellar regions as seeds for voxelwise analyses, we examined modafinil's modulation of cerebellar-neocortical connectivity. Next, we conducted a quantitative evaluation of the spatial overlap between the modulation of cerebellar-neocortical connectivity and the expression of neurotransmitter receptors/transporters obtained by publicly available databases. RESULTS: Modafinil increased the connectivity of crus I and vermis IX with prefrontal regions. Crus I connectivity changes were associated with the expression of dopaminergic D2 receptors. The vermis I-II showed enhanced coupling with the dorsal anterior cingulate cortex and matched the expression of histaminergic H3 receptors. The vermis VII-VIII displayed increased connectivity with the visual cortex, an activity associated with dopaminergic and histaminergic neurotransmission. CONCLUSIONS: Our study reveals modafinil's modulatory effects on cerebellar-neocortical connectivity. The modulation mainly involves crus I and the vermis and spatially overlaps the distribution of dopaminergic and histaminergic receptors.
- MeSH
- dospělí MeSH
- lidé MeSH
- magnetická rezonanční tomografie * MeSH
- mladý dospělý MeSH
- modafinil * farmakologie aplikace a dávkování MeSH
- mozeček * účinky léků diagnostické zobrazování metabolismus MeSH
- neokortex účinky léků metabolismus diagnostické zobrazování MeSH
- nervové dráhy účinky léků metabolismus MeSH
- stimulancia farmakologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- randomizované kontrolované studie MeSH
PURPOSE: The aim of this study was to develop a simple, robust, and easy-to-use calibration procedure for correcting misalignments in rosette MRI k-space sampling, with the objective of producing images with minimal artifacts. METHODS: Quick automatic calibration scans were proposed for the beginning of the measurement to collect information on the time course of the rosette acquisition trajectory. A two-parameter model was devised to match the measured time-varying readout gradient delays and approximate the actual rosette sampling trajectory. The proposed calibration approach was implemented, and performance assessment was conducted on both phantoms and human subjects. RESULTS: The fidelity of phantom and in vivo images exhibited significant improvement compared with uncorrected rosette data. The two-parameter calibration approach also demonstrated enhanced precision and reliability, as evidenced by quantitative T2*$$ {\mathrm{T}}_2^{\ast } $$ relaxometry analyses. CONCLUSION: Adequate correction of data sampling is a crucial step in rosette MRI. The presented experimental results underscore the robustness, ease of implementation, and suitability for routine experimental use of the proposed two-parameter rosette trajectory calibration approach.
- MeSH
- algoritmy * MeSH
- artefakty * MeSH
- fantomy radiodiagnostické * MeSH
- kalibrace MeSH
- lidé MeSH
- magnetická rezonanční tomografie * metody MeSH
- mozek diagnostické zobrazování MeSH
- počítačové zpracování obrazu * metody MeSH
- reprodukovatelnost výsledků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND OBJECTIVE: While prostate cancer (PCa) incidence and mortality rates continue to rise, early detection of PCa remains highly controversial, and the research landscape is rapidly evolving. Existing systematic reviews (SRs) and meta-analyses (MAs) provide valuable insights, but often focus on single aspects of early detection, hindering a comprehensive understanding of the topic. We aim to fill this gap by providing a comprehensive SR of contemporary SRs covering different aspects of early detection of PCa in the European Union (EU) and the UK. METHODS: On June 1, 2023, we searched four databases (Medline ALL via Ovid, Embase, Web of Science, and Cochrane Central Register of Controlled Trials) and Google Scholar. To avoid repetition of previous studies, only SRs (qualitative, quantitative, and/or MAs) were considered eligible. In the data, common themes were identified to present the evidence systematically. KEY FINDINGS AND LIMITATIONS: We identified 1358 citations, resulting in 26 SRs eligible for inclusion. Six themes were identified: (1) invitation: men at general risk should be invited at >50 yr of age, and testing should be discontinued at >70 yr or with <10 yr of life expectancy; (2) decision-making: most health authorities discourage population-based screening and instead recommend a shared decision-making (SDM) approach, but implementation of SDM in clinical practice varies widely; decision aids help men make more informed and value-consistent screening decisions and decrease men's intention to attempt screening, but these do not affect screening uptake; (3) acceptance: facilitators for men considering screening include social prompting by partners and clinician recommendations, while barriers include a lack of knowledge, low-risk perception, and masculinity attributes; (4) screening test and algorithm: prostate-specific antigen-based screening reduces PCa-specific mortality and metastatic disease in men aged 55-69 yr at randomisation if screened at least twice; (5) harms and benefits: these benefits come at the cost of unnecessary biopsies, overdiagnosis, and subsequent overtreatment; and (6) future of screening: risk-adapted screening including (prebiopsy) risk calculators, magnetic resonance imaging, and blood- and urine-based biomarkers could reduce these harms. To enable a comprehensive overview, we focused on SRs. These do not include the most recent prospective studies, which were therefore incorporated in the discussion. CONCLUSIONS AND CLINICAL IMPLICATIONS: By identifying consistent and conflicting evidence, this review highlights the evidence-based foundations that can be built upon, as well as areas requiring further research and improvement to reduce the burden of PCa in the EU and UK. PATIENT SUMMARY: This review of 26 reviews covers various aspects of prostate cancer screening such as invitation, decision-making, screening tests, harms, and benefits. This review provides insights into existing evidence, highlighting the areas of consensus and discrepancies, to guide future research and improve prostate cancer screening strategies in Europe.
- MeSH
- časná detekce nádoru * MeSH
- Evropská unie * MeSH
- lidé MeSH
- nádory prostaty * diagnóza MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Geografické názvy
- Spojené království MeSH
The intertumoral and intratumoral heterogeneity of colorectal adenocarcinoma (CRC) at the morphologic level is poorly understood. Previously, we identified morphological patterns associated with CRC molecular subtypes and their distinct molecular motifs. Here we aimed to evaluate the heterogeneity of these patterns across CRC. Three pathologists evaluated dominant, secondary, and tertiary morphology on four sections from four different FFPE blocks per tumor in a pilot set of 22 CRCs. An AI-based image analysis tool was trained on these tumors to evaluate the morphologic heterogeneity on an extended set of 161 stage I-IV primary CRCs (n = 644 H&E sections). We found that most tumors had two or three different dominant morphotypes and the complex tubular (CT) morphotype was the most common. The CT morphotype showed no combinatorial preferences. Desmoplastic (DE) morphotype was rarely dominant and rarely combined with other dominant morphotypes. Mucinous (MU) morphotype was mostly combined with solid/trabecular (TB) and papillary (PP) morphotypes. Most tumors showed medium or high heterogeneity, but no associations were found between heterogeneity and clinical parameters. A higher proportion of DE morphotype was associated with higher T-stage, N-stage, distant metastases, AJCC stage, and shorter overall survival (OS) and relapse-free survival (RFS). A higher proportion of MU morphotype was associated with higher grade, right side, and microsatellite instability (MSI). PP morphotype was associated with earlier T- and N-stage, absence of metastases, and improved OS and RFS. CT was linked to left side, lower grade, and better survival in stage I-III patients. MSI tumors showed higher proportions of MU and TB, and lower CT and PP morphotypes. These findings suggest that morphological shifts accompany tumor progression and highlight the need for extensive sampling and AI-based analysis. In conclusion, we observed unexpectedly high intratumoral morphological heterogeneity of CRC and found that it is not heterogeneity per se, but the proportions of morphologies that are associated with clinical outcomes.
- MeSH
- adenokarcinom * patologie genetika mortalita MeSH
- dospělí MeSH
- kolorektální nádory * patologie genetika mortalita MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- staging nádorů MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
One of the main challenges in analyzing chemical messengers in the brain is the optimization of tissue sampling and preparation protocols. Limiting postmortem time and terminating enzyme activity is critical to identify low-abundance neurotransmitters and neuropeptides. Here, we used a rapid and uniform conductive heat transfer stabilization method that was compared with a conventional fresh freezing protocol. Together with a selective chemical derivatization method and an optimized quantitation approach using deuterated internal standards, we spatially mapped neurotransmitters and their related metabolites by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) in rat brain tissue sections. Although the heat stabilization did not show differences in the levels of dopamine, norepinephrine, and serotonin, their related metabolites 3,4-dihydroxyphenylacetaldehyde, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 3-methoxy-4-hydroxyphenylacetaldehyde, dihydroxyphenylethyleneglycol, and 5-hydroxyindoleacetic acid were all significantly lower, indicating reduced neurotransmitter postmortem turnover ratios. Heat stabilization enabled detection of an increased number and higher levels of prodynorphin, proenkephalin, and tachykinin-derived bioactive neuropeptides. The low-abundant C-terminal flanking peptide, neuropeptide-γ, and nociceptin remained intact and were exclusively imaged in heat-stabilized brains. Without heat stabilization, degradation fragments of full-length peptides occurred in the fresh frozen tissues. The sample preparation protocols were furthermore tested on rat brains affected by acute anesthesia induced by isoflurane and medetomidine, showing comparable results to non-anesthetized animals on the neurotransmitters level without significant changes. Our data provide evidence for the potential use of heat stabilization prior to MALDI-MSI analyses to improve the examination of the in vivo state of neuronal chemical messengers in brain tissues not impacted by prior acute anesthesia.
- MeSH
- krysa rodu rattus MeSH
- mozek - chemie * fyziologie MeSH
- mozek * metabolismus MeSH
- neurony * metabolismus chemie MeSH
- neurotransmiterové látky * metabolismus analýza MeSH
- potkani Sprague-Dawley MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice * metody MeSH
- vysoká teplota * MeSH
- zmrazování MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to test the hypothesis that individuals with an increase in HbA1c (i.e. above the regular but below the diabetic threshold) exhibit an impairment in the Achilles tendon structure and walking capacity, due to the adverse effect of the advanced glycation end-product. One hundred fifty-eight participants matched for gender, age, physical activity and BMI, were divided in two cohorts based on the HbA1c level: normal HbA1c (NGH; <39 mmol/molHb; n = 79) and altered HbA1c (AGH; >=39 mmol/molHb; n = 79). Each participant performed several walking trials to evaluate the kinematic parameters during walling at the self-selected speed and a quantitative MRI scan of the Achilles tendon (AT) to obtain its intrinsic characteristics (i.e. T2* relaxation time short and long component). The AT T2* relaxation time short component (a parameter related to the tendon collagen quality) was reduced in AGH compared to NGH. Furthermore, AGH exhibited a slower self-selected walking speed (NGH: 1.59 ± 0.18 m/s; AGH:1.54 ± 0.16 m/s) and a shorter stride length (NGH: 1.59 ± 0.13 m; AGH:1.55 ± 0.11 m). Our data suggest that a non-pathological increase in HbA1c is able to negatively affect AT collagen quality and walking capacity in healthy people. These results highlight the importance of glycemic control, even below the pathological threshold. Since diabetes could alter several biological pathways, further studies are necessary to determine which mechanisms and their timing, regarding the HbA1c rise, affect tendon composition and, consequently, walking capacity.
- MeSH
- Achillova šlacha * diagnostické zobrazování fyziologie metabolismus MeSH
- biomechanika MeSH
- chůze * fyziologie MeSH
- diabetes mellitus diagnóza MeSH
- dospělí MeSH
- glykovaný hemoglobin * metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- produkty pokročilé glykace metabolismus MeSH
- zdraví dobrovolníci pro lékařské studie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: The hypothalamus (HT) plays a crucial role in regulating eating behaviors. Disruptions in its function have been linked to the development of weight-related disorders. Nevertheless, its characterization remains a challenge. OBJECTIVES: We assessed the structural alterations of individual HT nuclei related to eating behaviors in patients with weight-related disorders, and their association with body mass index (BMI) and severity of eating disorders. METHODS: Forty-four young females with normal weight (HC, n = 21), restrictive anorexia nervosa (AN, n = 13), and living with obesity (OB, n = 10) were explored in vivo using 7-T high-resolution (0.6 mm isotropic voxel) T1 quantitative magnetic resonance imaging (MRI). Volumes and quantitative T1 values of individual HT nuclei were compared after whole-brain normalization using nonparametric tests (corrected for multiple comparisons for groups and regions). We investigated the parameters associated with BMI and eating disorders, such as MRI parameters of HT nuclei, ghrelin and leptin levels, depression, and anxiety using multivariate nonlinear partial least square (NIPALS). RESULTS: Both AN and OB showed higher volumes of HT relative to HC (Zscores: 0.78 ± 1.06; 1.43 ± 1.51). AN showed significantly higher volumes and T1 values of the right paraventricular nucleus (PaVN) (volume Zscore: 1.82 ± 1.45; T1 Zscore: 3.76 ± 4.67), and higher T1 values of the left PaVN (Zscore: 2.25 ± 2.37) and right periventricular nuclei (Zscore: 3.73 ± 4.81). NIPALS models showed that lower BMI in AN was associated with structural alterations of the bilateral PaVN, right anterior commissure, and left fornix (FX). Higher BMI in OB was associated with structural alterations within the right PaVN, bilateral FX, left posterior hypothalamic nucleus, right lateral HT, and right anterior hypothalamic area. Finally, the severity of eating disorders was associated with larger structural alterations within the bilateral PaVN, bilateral arcuate hypothalamic nuclei, right bed nucleus of stria terminalis, left medial preoptic nucleus, and right tubero-mammillary hypothalamic nucleus. CONCLUSIONS: Weight-related disorders are associated with significant micro and macrostructural alterations in HT nuclei involved in eating behaviors.
- MeSH
- dospělí MeSH
- hypothalamus * diagnostické zobrazování patologie MeSH
- index tělesné hmotnosti MeSH
- leptin krev MeSH
- lidé MeSH
- magnetická rezonanční tomografie * MeSH
- mentální anorexie * diagnostické zobrazování patologie MeSH
- mladiství MeSH
- mladý dospělý MeSH
- obezita * diagnostické zobrazování patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: The diagnostic accuracy of prostate magnetic resonance imaging (MRI) is highly dependent on image quality. Although the effects of spasmolytics and rectal preparation have been previously studied, the findings remain inconsistent and fail to address other critical modifiable factors. This study aimed to evaluate the impact of various modifiable factors on prostate MRI image quality and their subsequent influence on Prostate Imaging Reporting and Data System (PI-RADS) scoring. METHODS: Fifty-six consecutive patients who underwent 3T multiparametric MRI (mpMRI) with the administration of hyoscine butylbromide (HB+) and at least one 3T mpMRI without HB (HB-) ≤3 years earlier were retrospectively evaluated. Two radiologists performed morphometry of the prostate, bladder, rectum, and abdomen and evaluated image quality, artifacts, and motion on a five-point scale and T2 and diffusion-weighted imaging (DWI) PI-RADS v2.1 scores. The influence of HB, rectum and bladder distension, breathing motion, and examination hour were analyzed. RESULTS: The sharpness and overall image quality of T2 images were significantly better in HB+ compared to HB- (P=0.0047 and P=0.013). T2 motion artifacts were reduced earlier in the day (ρ=0.32, P=0.017). DWI susceptibility artifact correlated with patient diameter (ρ=0.40, P=0.002), but not with rectum diameter (ρ=0.09, P=0.51) or gas content (ρ=0.13, P=0.33). Examinations later in the day were associated with increased motion artifacts on T2 [hazard ratio (HR) =1.36]. T2 and DWI scores were influenced by bladder volume, breathing motion, and rectal air, but not by HB. Breathing motion negatively impacted overall image quality (HR =1.24), and DWI susceptibility artifacts (HR =1.22). CONCLUSIONS: HB administration, daytime, and breathing motion have significant influence on image quality of prostate MRI. The gas content of the rectum influences T2 image quality and T2 scores. Bladder filling is associated with reduced breathing motion, subsequently affecting DWI scores.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: To validate the clinical utility of a previously identified circulating tumor DNA methylation marker (meth-ctDNA) panel for disease detection and survival outcomes, meth-ctDNA markers were compared to PSA levels and PSMA PET/CT findings in men with different stages of prostate cancer (PCa). METHODS: 122 PCa patients who underwent [68Ga]Ga-PSMA-11 PET/CT and plasma sampling (03/2019-08/2021) were analyzed. cfDNA was extracted, and a panel of 8 individual meth-ctDNA markers was queried. PET scans were qualitatively and quantitatively assessed. PSA and meth-ctDNA markers were compared to PET findings, and their relative prognostic value was evaluated. RESULTS: PSA discriminated best between negative and tumor-indicative PET scans in all (AUC 0.77) and hormone-sensitive (hsPC) patients (0.737). In castration-resistant PCa (CRPC), the meth-ctDNA marker KLF8 performed best (AUC 0.824). CHST11 differentiated best between non- and metastatic scans (AUC 0.705) overall, KLF8 best in hsPC and CRPC (AUC 0.662, 0.85). Several meth-ctDNA markers correlated low to moderate with the tumor volume in all (5/8) and CRPC patients (6/8), while PSA levels correlated moderately to strongly with the tumor volume in all groups (all p < 0.001). CRPC overall survival was independently associated with LDAH and PSA (p = 0.0168, p < 0.001). CONCLUSION: The studied meth-ctDNA markers are promising for the minimally-invasive detection and prognostication of CRPC but do not allow for clinical characterization of hsPC. Prospective studies are warranted for their use in therapy response and outcome prediction in CRPC and potential incremental value for PCa monitoring in PSA-low settings.
- MeSH
- cirkulující nádorová DNA genetika krev MeSH
- EDTA analogy a deriváty MeSH
- izotopy gallia * MeSH
- lidé středního věku MeSH
- lidé MeSH
- metylace DNA * genetika MeSH
- nádorové biomarkery * genetika krev MeSH
- nádory prostaty rezistentní na kastraci genetika krev diagnostické zobrazování MeSH
- nádory prostaty * genetika krev diagnostické zobrazování MeSH
- PET/CT * metody MeSH
- prognóza MeSH
- prostatický specifický antigen * krev genetika MeSH
- průřezové studie MeSH
- radioizotopy galia * MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
INTRODUCTION: Muscle magnetic resonance imaging (MRI) is an emerging method in the diagnosis and monitoring of muscular dystrophies. This cross-sectional, comparative study aimed to evaluate quantitative MRI (qMRI) parameters of the lumbar paraspinal muscles (LPM) in myotonic dystrophy type 2 (DM2), to assess their relationship with functional examination, and to evaluate their evolution with aging. METHODS: The study enrolled 37 DM2 patients and 90 healthy volunteers (HV) who were matched based on physiological parameters to create 35 pairs. Utilizing a 6-point Dixon gradient echo sequence MRI, fat fraction (FF), total muscle volume, and functional muscle volume (FMV) of the LPM and psoas muscle (PS) were obtained. Using correlation coefficients and regression models, the relationship between MRI and the maximal isometric lumbar extensor muscle strength (MILEMS) and lumbar extensor muscle endurance (LEME), and their evolution with age, were assessed. RESULTS: LPM showed significantly higher FF in DM2 patients compared to HV (21.3% vs. 11.3%, p-value <0.001). FMV of LPM correlated significantly with MILEMS (ρ = 0.5, p- value = 0.001) and FF with LEME (ρ = -0.49, p- value = 0.002) in DM2. No significant differences in the rate of deterioration in functional and morphological parameters of the LPM with age were observed between the two groups. CONCLUSION: We demonstrated morphological correlates of lumbar extensor muscle dysfunction in DM2 patients. The qMRI parameters of LPM correlated with functional parameters but could not be used either as a reliable biomarker of lumbar extensor muscle impairment or as a biomarker of disease progression.
- Publikační typ
- časopisecké články MeSH