Diversity of oncopharmacogenetic profile within Spanish population.

Consensus guidelines for genotype-guided fluoropyrimidine dosing based on variation in the dihydropyrimidine dehydrogenase (DPYD) gene before treatment have been firmly established. The prior pharmacogenetic report avoids the serious toxicity that inevitably occurred in a non-negligible percentage of the treated patients. The precise description of the allelic distribution of the variants of interest in our reference populations is information of great interest for the management of the prescription of these antineoplastic drugs. We characterized the allelic distribution of the UGT1A1*28 variant (rs3064744), as well as the DPYD*2A (rs3918290) variant, c.1679T>G (rs55886062), c.2846A>T (rs67376798) and c.1129-5923C>G (rs75017182; HapB3) in series of 5251 patients who are going to receive treatment with irinotecan and fluoropyrimidines, representative of Valencian, Aragonese and Western Andalusian populations.

A toolbox of engineered mosquito lines to study salivary gland biology and malaria transmission.

Mosquito saliva is a vehicle for the transmission of vector borne pathogens such as Plasmodium parasites and different arboviruses. Despite the key role of the salivary glands in the process of disease transmission, knowledge of host-pathogen interactions taking place within this organ is very limited. To improve the experimental tractability of the salivary glands, we have generated fluorescent reporter lines in the African malaria mosquito Anopheles coluzzii using the salivary gland-specific promoters of the anopheline antiplatelet protein (AAPP), the triple functional domain protein (TRIO) and saglin (SAG) coding genes. Promoter activity was specifically observed in the distal-lateral lobes or in the median lobe of the salivary glands. Besides a comparison of the expression patterns of the selected promoters, the fluorescent probes allowed us to evaluate the inducibility of the selected promoters upon blood feeding and to measure intracellular redox changes. We also combined the aapp-DsRed fluorescent reporter line with a pigmentation-deficient yellow(-) mosquito mutant to assess the feasibility of in vivo microscopy of parasitized salivary glands. This combination allowed locating the salivary gland through the cuticle and imaging of individual sporozoites in vivo, which facilitates live imaging studies of salivary gland colonization by Plasmodium sporozoites.

Neurodevelopmental assessment of normocephalic children born to Zika virus exposed and unexposed pregnant people.

BACKGROUND: Studies examining the association between in utero Zika virus (ZIKV) exposure and child neurodevelopmental outcomes have produced varied results. METHODS: We aimed to assess neurodevelopmental outcomes among normocephalic children born from pregnant people enrolled in the Zika in Pregnancy in Honduras (ZIPH) cohort study, July-December 2016. Enrollment occurred during the first prenatal visit. Exposure was defined as prenatal ZIKV IgM and/or ZIKV RNA result at enrollment. Normocephalic children, >6 months old, were selected for longitudinal follow-up using the Bayley Scales of Infant and Toddler Development (BSID-III) and the Ages & Stages Questionnaires: Social-Emotional (ASQ:SE-2). RESULTS: One hundred fifty-two children were assessed; after exclusion, 60 were exposed and 72 were unexposed to ZIKV during pregnancy. Twenty children in the exposed group and 21 children in the unexposed group had a composite score <85 in any of the BSID-III domains. Although exposed children had lower cognitive and language scores, differences were not statistically significant. For ASQ:SE-2 assessment, there were not statistically significant differences between groups. CONCLUSIONS: This study found no statistically significant differences in the neurodevelopment of normocephalic children between in utero ZIKV exposed and unexposed. Nevertheless, long-term monitoring of children with in utero ZIKV exposure is warranted. IMPACT: This study found no statistically significant differences in the neurodevelopment in normocephalic children with in utero Zika virus exposure compared to unexposed children, although the exposed group showed lower cognitive and language scores that persisted after adjustment by maternal age and education and after excluding children born preterm and low birth weight from the analysis. Children with prenatal Zika virus exposure, including those normocephalic and have no evidence of abnormalities at birth, should be monitored for neurodevelopmental delays. Follow-up is important to be able to detect developmental abnormalities that might not be detected earlier in life.

Let it glow: genetically encoded fluorescent reporters in Plasmodium.

The use of fluorescent proteins (FPs) in Plasmodium parasites has been key to understand the biology of this obligate intracellular protozoon. FPs like the green fluorescent protein (GFP) enabled to explore protein localization, promoter activity as well as dynamic processes like protein export and endocytosis. Furthermore, FP biosensors have provided detailed information on physiological parameters at the subcellular level, and fluorescent reporter lines greatly extended the malariology toolbox. Still, in order to achieve optimal results, it is crucial to know exactly the properties of the FP of choice and the genetic scenario in which it will be used. This review highlights advantages and disadvantages of available landing sites and promoters that have been successfully applied for the ectopic expression of FPs in Plasmodium berghei and Plasmodium falciparum. Furthermore, the properties of newly developed FPs beyond DsRed and EGFP, in the visualization of cells and cellular structures as well as in the sensing of small molecules are discussed.

Differentiating IDH-mutant astrocytomas and 1p19q-codeleted oligodendrogliomas using DSC-PWI: high performance through cerebral blood volume and percentage of signal recovery percentiles.

OBJECTIVE: Presurgical differentiation between astrocytomas and oligodendrogliomas remains an unresolved challenge in neuro-oncology. This research aims to provide a comprehensive understanding of each tumor's DSC-PWI signatures, evaluate the discriminative capacity of cerebral blood volume (CBV) and percentage of signal recovery (PSR) percentile values, and explore the synergy of CBV and PSR combination for pre-surgical differentiation. METHODS: Patients diagnosed with grade 2 and 3 IDH-mutant astrocytomas and IDH-mutant 1p19q-codeleted oligodendrogliomas were retrospectively retrieved (2010-2022). 3D segmentations of each tumor were conducted, and voxel-level CBV and PSR were extracted to compute mean, minimum, maximum, and percentile values. Statistical comparisons were performed using the Mann-Whitney U test and the area under the receiver operating characteristic curve (AUC-ROC). Lastly, the five most discriminative variables were combined for classification with internal cross-validation. RESULTS: The study enrolled 52 patients (mean age 45-year-old, 28 men): 28 astrocytomas and 24 oligodendrogliomas. Oligodendrogliomas exhibited higher CBV and lower PSR than astrocytomas across all metrics (e.g., mean CBV = 2.05 and 1.55, PSR = 0.68 and 0.81 respectively). The highest AUC-ROCs and the smallest p values originated from CBV and PSR percentiles (e.g., PSRp70 AUC-ROC = 0.84 and p value = 0.0005, CBVp75 AUC-ROC = 0.8 and p value = 0.0006). The mean, minimum, and maximum values yielded lower results. Combining the best five variables (PSRp65, CBVp70, PSRp60, CBVp75, and PSRp40) achieved a mean AUC-ROC of 0.87 for differentiation. CONCLUSIONS: Oligodendrogliomas exhibit higher CBV and lower PSR than astrocytomas, traits that are emphasized when considering percentiles rather than mean or extreme values. The combination of CBV and PSR percentiles results in promising classification outcomes. CLINICAL RELEVANCE STATEMENT: The combination of histogram-derived percentile values of cerebral blood volume and percentage of signal recovery from DSC-PWI enhances the presurgical differentiation between astrocytomas and oligodendrogliomas, suggesting that incorporating these metrics into clinical practice could be beneficial. KEY POINTS: • The unsupervised selection of percentile values for cerebral blood volume and percentage of signal recovery enhances presurgical differentiation of astrocytomas and oligodendrogliomas. • Oligodendrogliomas exhibit higher cerebral blood volume and lower percentage of signal recovery than astrocytomas. • Cerebral blood volume and percentage of signal recovery combined provide a broader perspective on tumor vasculature and yield promising results for this preoperative classification.

Impacts of early deprivation on behavioral and neural measures of executive function in early adolescence.

Children reared in institutional settings experience early deprivation that has lasting implications for multiple aspects of neurocognitive functioning, including executive function (EF). Changes in brain development are thought to contribute to these persistent EF challenges, but little research has used fMRI to investigate EF-related brain activity in children with a history of early deprivation. This study examined behavioral and neural data from a response conflict task in 12-14-year-olds who spent varying lengths of time in institutional care prior to adoption (N = 84; age at adoption - mean: 15.85 months, median: 12 months, range: 4-60 months). In initial analyses, earlier- and later-adopted (EA, LA) youth were compared to a group of children raised in their biological families (non-adopted, NA). NA youth performed significantly more accurately than LA youth, with EA youth falling in between. Imaging data suggested that previously institutionalized (PI) youth activated additional frontoparietal regions, including dorsolateral prefrontal cortex, as compared to NA youth. In addition, EA youth uniquely activated medial prefrontal regions, and LA uniquely activated parietal regions during this task. A separate analysis in a larger group of PI youth examined whether behavioral or brain measures of EF varied with the duration of deprivation experienced. Duration of deprivation was negatively associated with activation of default mode network (DMN) regions. Overall, results suggest that there are lasting effects of deprivation on EF, but that those who are removed from institutional care earlier may be able to recruit additional neural resources as a compensatory mechanism.

Long-Term Outcomes of the Altis® Single-Incision Sling: Up to 10 Years' Follow-up.

INTRODUCTION AND HYPOTHESIS: Single-incision slings (SIS) have emerged as a less invasive alternative to conventional slings for stress urinary incontinence (SUI) treatment. However, long-term efficacy and safety results remain uncertain owing to a lack of studies. MATERIAL AND METHODS: A retrospective review of 155 patients treated with Altis® for SUI between February 2012 and June 2017, held in 2022, as a continuation of a prospective study in which all patients (197) were reviewed for 2 years after surgery (1, 6, 12, and 24 months). Preoperative demographic data, comorbidities, and pressure-flow studies were also recorded. Continence status and satisfaction rates were assessed using the International Consultation on Incontinence Questionnaire-short form (ICIQ-SF) and the Patient Global Impression of Improvement (PGI-I) respectively. The assessment in the 2022 retrospective review was performed via a telephone survey. RESULTS: Mean follow-up time after surgery was 85.3 months (82.5-88.1). In 2022, complete continence was present in 75.4% of the patients. The presence of urinary urgency conditioned the ICIQ-SF score (10.9 vs 1.7 points, p < 0.01), with the ICIQ-SF = 0 in 84.5% of the patients with no associated urgency. Satisfaction assessed by the PGI-I was high, with 84.6% of the patients showing improvement. De novo urgency was present in 37,9% of the patients by 2022. Urinary tract infections were the most frequent complication (9.7%), with only 5 documented cases of mesh erosion. CONCLUSIONS: Altis® SIS is a safe and effective device for SUI treatment, with satisfaction rates comparable with those of the conventional slings. Persistence or development of urinary urgency influences the results.

Pericytes Are Immunoregulatory Cells in Glioma Genesis and Progression.

Vascular co-option is a consequence of the direct interaction between perivascular cells, known as pericytes (PCs), and glioblastoma multiforme (GBM) cells (GBMcs). This process is essential for inducing changes in the pericytes' anti-tumoral and immunoreactive phenotypes. Starting from the initial stages of carcinogenesis in GBM, PCs conditioned by GBMcs undergo proliferation, acquire a pro-tumoral and immunosuppressive phenotype by expressing and secreting immunosuppressive molecules, and significantly hinder the activation of T cells, thereby facilitating tumor growth. Inhibiting the pericyte (PC) conditioning mechanisms in the GBM tumor microenvironment (TME) results in immunological activation and tumor disappearance. This underscores the pivotal role of PCs as a key cell in the TME, responsible for tumor-induced immunosuppression and enabling GBM cells to evade the immune system. Other cells within the TME, such as tumor-associated macrophages (TAMs) and microglia, have also been identified as contributors to this immunomodulation. In this paper, we will review the role of these three cell types in the immunosuppressive properties of the TME. Our conclusion is that the cellular heterogeneity of immunocompetent cells within the TME may lead to the misinterpretation of cellular lineage identification due to different reactive stages and the identification of PCs as TAMs. Consequently, novel therapies could be developed to disrupt GBM-PC interactions and/or PC conditioning through vascular co-option, thereby exposing GBMcs to the immune system.

Genomic landscapes of ovarian clear cell carcinoma from latin countries reveal aberrations linked to survival and progression.

BACKGROUND: Ovarian clear cell carcinomas (OCCCs) are rare, aggressive and chemoresistant tumors. Geographical and ethnic differences in the incidence of OCCC have been reported with a higher incidence in Asiatic countries. There is a paucity of information regarding OCCC in Latin America (LA) and other countries. METHODS: Here, we characterized two cohorts of 33 patients with OCCC from LA (24 from Brazil and 9 from Costa Rica) and a cohort of 27 patients from Spain. Genomic analysis was performed for 26 OCCC using the OncoScan platform. Tumors were classified according to their genomic landscapes into subgroups. Clinical parameters were related to the frequency of genomic aberrations. RESULTS: The median overall survival (OS) was not significantly different between the cohorts. Genomic landscapes were characterized by different homologous recombination deficiency (HRD) levels. No difference in the distribution of genomic landscapes profiles was detected between patients from the different cohorts. OCCCs with MYC-amplified tumors harboring a concomitant loss of a region in chromosome 13q12-q13 that includes the BRCA2 gene had the longest OS. In contrast, patients carrying a high number (> 30) of total copy number (CN) aberrations with no concomitant alterations in MYC and BRCA2 genes presented the shortest OS. Furthermore, amplification of the ASH1L gene was also associated with a shorter OS. Initial-stage OCCCs with early progression were characterized by gains in the JNK1 and MKL1 genes. CONCLUSIONS: Our results provide new data from understudied OCCC populations and reveal new potential markers for OCCCs.

Advanced Diffusion-Weighted MRI for Cancer Microstructure Assessment in Body Imaging, and Its Relationship With Histology.

Diffusion-weighted magnetic resonance imaging (DW-MRI) aims to disentangle multiple biological signal sources in each imaging voxel, enabling the computation of innovative maps of tissue microstructure. DW-MRI model development has been dominated by brain applications. More recently, advanced methods with high fidelity to histology are gaining momentum in other contexts, for example, in oncological applications of body imaging, where new biomarkers are urgently needed. The objective of this article is to review the state-of-the-art of DW-MRI in body imaging (ie, not including the nervous system) in oncology, and to analyze its value as compared to reference colocalized histology measurements, given that demonstrating the histological validity of any new DW-MRI method is essential. In this article, we review the current landscape of DW-MRI techniques that extend standard apparent diffusion coefficient (ADC), describing their acquisition protocols, signal models, fitting settings, microstructural parameters, and relationship with histology. Preclinical, clinical, and in/ex vivo studies were included. The most used techniques were intravoxel incoherent motion (IVIM; 36.3% of used techniques), diffusion kurtosis imaging (DKI; 16.7%), vascular, extracellular, and restricted diffusion for cytometry in tumors (VERDICT; 13.3%), and imaging microstructural parameters using limited spectrally edited diffusion (IMPULSED; 11.7%). Another notable category of techniques relates to innovative b-tensor diffusion encoding or joint diffusion-relaxometry. The reviewed approaches provide histologically meaningful indices of cancer microstructure (eg, vascularization/cellularity) which, while not necessarily accurate numerically, may still provide useful sensitivity to microscopic pathological processes. Future work of the community should focus on improving the inter-/intra-scanner robustness, and on assessing histological validity in broader contexts. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 2.

MR dynamic-susceptibility-contrast perfusion metrics in the presurgical discrimination of adult solitary intra-axial cerebellar tumors.

OBJECTIVES: Adult solitary intra-axial cerebellar tumors are uncommon. Their presurgical differentiation based on neuroimaging is crucial, since management differs substantially. Comprehensive full assessment of MR dynamic-susceptibility-contrast perfusion-weighted imaging (DSC-PWI) may reveal key differences between entities. This study aims to provide new insights on perfusion patterns of these tumors and to explore the potential of DSC-PWI in their presurgical discrimination. METHODS: Adult patients with a solitary cerebellar tumor on presurgical MR and confirmed histological diagnosis of metastasis, medulloblastoma, hemangioblastoma, or pilocytic astrocytoma were retrospectively retrieved (2008-2023). Volumetric segmentation of tumors and normal-appearing white matter (for normalization) was semi-automatically performed on CE-T1WI and coregistered with DSC-PWI. Mean normalized values per patient tumor-mask of relative cerebral blood volume (rCBV), percentage of signal recovery (PSR), peak height (PH), and normalized time-intensity curves (nTIC) were extracted. Statistical comparisons were done. Then, the dataset was split into training (75%) and test (25%) cohorts and a classifier was created considering nTIC, rCBV, PSR, and PH in the model. RESULTS: Sixty-eight patients (31 metastases, 13 medulloblastomas, 13 hemangioblastomas, and 11 pilocytic astrocytomas) were included. Relevant differences between tumor types' nTICs were demonstrated. Hemangioblastoma showed the highest rCBV and PH, pilocytic astrocytoma the highest PSR. All parameters showed significant differences on the Kruskal-Wallis tests (p < 0.001). The classifier yielded an accuracy of 98% (47/48) in the training and 85% (17/20) in the test sets. CONCLUSIONS: Intra-axial cerebellar tumors in adults have singular and significantly different DSC-PWI signatures. The combination of perfusion metrics through data-analysis rendered excellent accuracies in discriminating these entities. CLINICAL RELEVANCE STATEMENT: In this study, the authors constructed a classifier for the non-invasive imaging presurgical diagnosis of adult intra-axial cerebellar tumors. The resultant tool can be a support for decision-making in the clinical practice and enables optimal personalized patient management. KEY POINTS: • Adult intra-axial cerebellar tumors exhibit specific, singular, and statistically significant different MR dynamic-susceptibility-contrast perfusion-weighted imaging (DSC-PWI) signatures. • Data-analysis, applied to MR DSC-PWI, could provide added value in the presurgical diagnosis of solitary cerebellar metastasis, medulloblastoma, hemangioblastoma, and pilocytic astrocytoma. • A classifier based on DSC-PWI metrics yields excellent accuracy rates and could be used as a support tool for radiologic diagnosis with clinician-friendly displays.

Proton Pump Inhibitor Therapy in Pediatric Eosinophilic Esophagitis: Predictive Factors and Long-Term Step-Down Efficacy.

OBJECTIVES: To assess the short- and long-term efficacy of proton pump inhibitor (PPI) therapy for pediatric eosinophilic esophagitis (EoE) in real-world practice with a step-down strategy, and to evaluate factors predictive of PPI responsiveness. METHODS: We collected data regarding the efficacy of PPIs during this cross-sectional analysis of the prospective nationwide RENESE registry. Children with EoE treated with PPI monotherapy were included. Histological remission was defined as a peak eosinophilic count of <15 eosinophils (eos)/high-power field (hpf). Factors associated with PPI responsiveness were identified using multivariate logistic regression analysis. RESULTS: After induction therapy, histological and clinico-histological remission were observed in 51.4% (n = 346) and 46.5% of children, respectively. Normal endoscopic appearance of the esophagus was associated with a higher possibility [odds ratio (OR), 9.20; 95% confidence interval (CI), 2.10-40.16], and fibrostenotic phenotype was associated with a lower possibility (OR, 0.36; 95% CI, 0.18-0.74) of histological remission. Long-term therapy with a step-down strategy effectively maintained histological remission in 68.5% and 85.3% of children at 7 months (n = 108) and 16 months (n = 34), respectively. Complete initial histological remission (≤5 eos/hpf) was associated with a higher possibility of sustained histological remission (OR, 5.08; 95% CI, 1.75-14.68). Adverse events were infrequent and mild. CONCLUSIONS: We confirmed the efficacy of PPIs for a large cohort of children with EoE with sustained histological remission using a step-down strategy. Children with fibrostenotic phenotypes are less likely to respond to induction therapy. Furthermore, patients with complete initial histological remission are more likely to experience long-term histological remission.

Computational mechanisms underpinning greater exploratory behaviour in excess weight relative to healthy weight adolescents.

Obesity in adolescence is associated with cognitive changes that lead to difficulties in shifting unhealthy habits in favour of alternative healthy behaviours, similar to addictive behaviours. An outstanding question is whether this shift in goal-directed behaviour is driven by over-exploitation or over-exploration of rewarding outcomes. Here, we addressed this question by comparing explore/exploit behaviour on the Iowa Gambling Task in 43 adolescents with excess weight against 38 adolescents with healthy weight. We computationally modelled both exploitation behaviour (e.g., reinforcement sensitivity and inverse decay parameters), and explorative behaviour (e.g., maximum directed exploration value). We found that overall, adolescents with excess weight displayed more behavioural exploration than their healthy-weight counterparts - specifically, demonstrating greater overall switching behaviour. Computational models revealed that this behaviour was driven by a higher maximum directed exploration value in the excess-weight group (U = 520.00, p = .005, BF10 = 5.11). Importantly, however, we found substantial evidence that groups did not differ in reinforcement sensitivity (U = 867.00, p = .641, BF10 = 0.30). Overall, our study demonstrates a preference for exploratory behaviour in adolescents with excess weight, independent of sensitivity to reward. This pattern could potentially underpin an intrinsic desire to explore energy-dense unhealthy foods - an as-yet untapped mechanism that could be targeted in future treatments of obesity in adolescents.

Antileishmanial effects of Crotalaria spectabilis Roth aqueous extracts on Leishmania amazonensis.

Fifteen polar extracts from leaf, seed, pod, stem, flower and root of Crotalaria spectabilis were prepared using aqueous systems, based on the principles of green chemistry, and showed different protease inhibitor (PI) activities on trypsin, papain, pepsin and the extracellular L. amazonensis serine protease (LSPIII). The most pronounced inhibitory effect on LSPIII was observed in leaf (CS-P), root, stem, flower (CS-FPVPP) and pod (CS-VA) extracts. Crotalaria extracts exhibited low cytotoxicity on macrophages; however, they decreased the viability of L. amazonensis promastigotes and amastigotes, as observed in leaf (CS-AE, CS-P, CS-T and CS-PVPP), seed (CS-ST), flower and root (CS-RA) extracts. CS-P was chosen to study PI and secondary metabolites and a 10-12 kDa protein, analyzed by mass spectrometry, was identified as a serine PI homologous with papaya latex serine PI. Glycosylated flavonoids, such as quercetins, vitexin and tricin were the major secondary metabolites of CS-P. The presence of PIs in C. spectabilis is a new finding, especially in other organs than seeds since PIs have been reported only in seed legumes. Besides, this is the first report of antileishmanial activity of C. spectabilis extracts and the identification of serine polypeptide PI and glycosylated flavonoids from leaf.

Effect of Conventional Spinal Cord Stimulation on Serum Protein Profile in Patients With Persistent Spinal Pain Syndrome: A Case-Control Study.

BACKGROUND: Spinal cord stimulation (SCS) provides pain relief for most patients with persistent spinal pain syndrome type 2 (PSPS 2). Evidence is mounting on molecular changes induced by SCS as one of the mechanisms to explain pain improvement. We report the SCS effect on serum protein expression in vivo in patients with PSPS 2. MATERIALS AND METHODS: Serum proteins were identified and quantified using mass spectrometry. Proteins with significantly different expression among patients with PSPS 2 relative to controls, responders, and nonresponders to SCS, or significantly modulated by SCS relative to baseline, were identified. Those most correlated with the presence and time course of pain were selected using multivariate discriminant analysis. Bioinformatic tools were used to identify related biological processes. RESULTS: Thirty patients with PSPS 2, of whom 23 responded to SCS, were evaluated, together with 14 controls with no pain who also had undergone lumbar spinal surgery. A significant improvement in pain intensity, disability, and quality of life was recorded among responders. Five proteins differed significantly at baseline between patients with PSPS 2 and controls, with three proteins, mostly involved in immune processes and inflammation, being downregulated and two, mostly involved in vitamin metabolism, synaptic transmission, and restorative processes, being upregulated. In addition, four proteins, mostly related to immune processes and inflammation, decreased significantly, and three, mostly related to iron metabolism and containment of synaptic sprouting, increased significantly during SCS. CONCLUSION: This study identifies various biological processes that may underlie PSPS 2 pain and SCS therapeutic effects, including the modulation of neuroimmune response and inflammation, synaptic sprouting, vitamin and iron metabolism, and restorative processes.

Diffusion MRI signal cumulants and hepatocyte microstructure at fixed diffusion time: Insights from simulations, 9.4T imaging, and histology.

PURPOSE: Relationships between diffusion-weighted MRI signals and hepatocyte microstructure were investigated to inform liver diffusion MRI modeling, focusing on the following question: Can cell size and diffusivity be estimated at fixed diffusion time, realistic SNR, and negligible contribution from extracellular/extravascular water and exchange? METHODS: Monte Carlo simulations were performed within synthetic hepatocytes for varying cell size/diffusivity L / D0 , and clinical protocols (single diffusion encoding; maximum b-value: {1000, 1500, 2000} s/mm2 ; 5 unique gradient duration/separation pairs; SNR = { ∞ , 100, 80, 40, 20}), accounting for heterogeneity in (D0,L) and perfusion contamination. Diffusion ( D ) and kurtosis ( K ) coefficients were calculated, and relationships between (D0,L) and (D,K) were visualized. Functions mapping (D,K) to (D0,L) were computed to predict unseen (D0,L) values, tested for their ability to classify discrete cell-size contrasts, and deployed on 9.4T ex vivo MRI-histology data of fixed mouse livers RESULTS: Relationships between (D,K) and (D0,L) are complex and depend on the diffusion encoding. Functions mapping D,K to (D0,L) captures salient characteristics of D0(D,K) and L(D,K) dependencies. Mappings are not always accurate, but they enable just under 70% accuracy in a three-class cell-size classification task (for SNR = 20, bmax = 1500 s/mm2 , δ = 20 ms, and Δ = 75 ms). MRI detects cell-size contrasts in the mouse livers that are confirmed by histology, but overestimates the largest cell sizes. CONCLUSION: Salient information about liver cell size and diffusivity may be retrieved from minimal diffusion encodings at fixed diffusion time, in experimental conditions and pathological scenarios for which extracellular, extravascular water and exchange are negligible.

Voxel-level analysis of normalized DSC-PWI time-intensity curves: a potential generalizable approach and its proof of concept in discriminating glioblastoma and metastasis.

OBJECTIVE: Standard DSC-PWI analyses are based on concrete parameters and values, but an approach that contemplates all points in the time-intensity curves and all voxels in the region-of-interest may provide improved information, and more generalizable models. Therefore, a method of DSC-PWI analysis by means of normalized time-intensity curves point-by-point and voxel-by-voxel is constructed, and its feasibility and performance are tested in presurgical discrimination of glioblastoma and metastasis. METHODS: In this retrospective study, patients with histologically confirmed glioblastoma or solitary-brain-metastases and presurgical-MR with DSC-PWI (August 2007-March 2020) were retrieved. The enhancing tumor and immediate peritumoral region were segmented on CE-T1wi and coregistered to DSC-PWI. Time-intensity curves of the segmentations were normalized to normal-appearing white matter. For each participant, average and all-voxel-matrix of normalized-curves were obtained. The 10 best discriminatory time-points between each type of tumor were selected. Then, an intensity-histogram analysis on each of these 10 time-points allowed the selection of the best discriminatory voxel-percentile for each. Separate classifier models were trained for enhancing tumor and peritumoral region using binary logistic regressions. RESULTS: A total of 428 patients (321 glioblastomas, 107 metastases) fulfilled the inclusion criteria (256 men; mean age, 60 years; range, 20-86 years). Satisfactory results were obtained to segregate glioblastoma and metastases in training and test sets with AUCs 0.71-0.83, independent accuracies 65-79%, and combined accuracies up to 81-88%. CONCLUSION: This proof-of-concept study presents a different perspective on brain MR DSC-PWI evaluation by the inclusion of all time-points of the curves and all voxels of segmentations to generate robust diagnostic models of special interest in heterogeneous diseases and populations. The method allows satisfactory presurgical segregation of glioblastoma and metastases. KEY POINTS: • An original approach to brain MR DSC-PWI analysis, based on a point-by-point and voxel-by-voxel assessment of normalized time-intensity curves, is presented. • The method intends to extract optimized information from MR DSC-PWI sequences by impeding the potential loss of information that may represent the standard evaluation of single concrete perfusion parameters (cerebral blood volume, percentage of signal recovery, or peak height) and values (mean, maximum, or minimum). • The presented approach may be of special interest in technically heterogeneous samples, and intrinsically heterogeneous diseases. Its application enables satisfactory presurgical differentiation of GB and metastases, a usual but difficult diagnostic challenge for neuroradiologist with vital implications in patient management.

Quantification and reduction of cross-vendor variation in multicenter DWI MR imaging: results of the Cancer Core Europe imaging task force.

OBJECTIVES: In the Cancer Core Europe Consortium (CCE), standardized biomarkers are required for therapy monitoring oncologic multicenter clinical trials. Multiparametric functional MRI and particularly diffusion-weighted MRI offer evident advantages for noninvasive characterization of tumor viability compared to CT and RECIST. A quantification of the inter- and intraindividual variation occurring in this setting using different hardware is missing. In this study, the MRI protocol including DWI was standardized and the residual variability of measurement parameters quantified. METHODS: Phantom and volunteer measurements (single-shot T2w and DW-EPI) were performed at the seven CCE sites using the MR hardware produced by three different vendors. Repeated measurements were performed at the sites and across the sites including a traveling volunteer, comparing qualitative and quantitative ROI-based results including an explorative radiomics analysis. RESULTS: For DWI/ADC phantom measurements using a central post-processing algorithm, the maximum deviation could be decreased to 2%. However, there is no significant difference compared to a decentralized ADC value calculation at the respective MRI devices. In volunteers, the measurement variation in 2 repeated scans did not exceed 11% for ADC and is below 20% for single-shot T2w in systematic liver ROIs. The measurement variation between sites amounted to 20% for ADC and < 25% for single-shot T2w. Explorative radiomics classification experiments yield better results for ADC than for single-shot T2w. CONCLUSION: Harmonization of MR acquisition and post-processing parameters results in acceptable standard deviations for MR/DW imaging. MRI could be the tool in oncologic multicenter trials to overcome the limitations of RECIST-based response evaluation. KEY POINTS: • Harmonizing acquisition parameters and post-processing homogenization, standardized protocols result in acceptable standard deviations for multicenter MR-DWI studies. • Total measurement variation does not to exceed 11% for ADC in repeated measurements in repeated MR acquisitions, and below 20% for an identical volunteer travelling between sites. • Radiomic classification experiments were able to identify stable features allowing for reliable discrimination of different physiological tissue samples, even when using heterogeneous imaging data.

Spanish National Registry of Paediatric Coeliac Disease: Changes in the Clinical Presentation in the 21st Century.

OBJECTIVES: Over the last several decades, there has been a tendency towards a predominance of less symptomatic forms of coeliac disease (CD) and an increase in the patient age at diagnosis. This study aimed to assess the clinical presentation and diagnostic process of paediatric CD in Spain. METHODS: A nationwide prospective, observational, multicentre registry of new paediatric CD cases was conducted from January 2011 to June 2017. The data regarding demographic variables, type of birth, breast-feeding history, family history of CD, symptoms, height and weight, associated conditions, serological markers, human leukocyte antigen (HLA) phenotype, and histopathological findings were collected. RESULTS: In total, 4838 cases (61% girls) from 73 centres were registered. The median age at diagnosis was 4 years. Gastrointestinal symptoms were detected in 71.4% of the patients, and diarrhoea was the most frequent symptom (45.9%). The most common clinical presentation was the classical form (65.1%) whereas 9.8% ofthe patients were asymptomatic. There was a trend towards an increase in the age at diagnosis, proportion of asymptomatic CD cases, and usage of anti-deamidated gliadin peptide antibodies and HLA typing for CD diagnosis. There was, however, a decreasing trend in the proportion of patients undergoing biopsies. Some of these significant trend changes may reflect the effects of the 2012 ESPGHAN diagnosis guidelines. CONCLUSIONS: Paediatric CD in Spain is evolving in the same direction as in the rest of Europe, although classical CD remains the most common presentation form, and the age at diagnosis remains relatively low.

Correlation of Anti-Tissue Transglutaminase Antibodies With the Mucosal Changes and IgA Status of Children With Celiac Disease.

OBJECTIVES: The objective of this study was to assess the association between serological markers and changes of the intestinal mucosa in children with celiac disease (CD). METHODS: Clinical data from CD patients under 15 years old were collected from the participating centers in an on-line multicenter nationwide observational Spanish registry called REPAC-2 (2011-2017). Correlation between anti-tissue transglutaminase antibodies (t-TGA) levels and other variables, including mucosal damage and clinical findings (symptoms, age, and gender), was assessed. RESULTS: A total of 2955 of 4838 patients had t-TGA and a small bowel biopsy (SBB) performed for CD diagnosis. A total of 1931 (66.2%) patients with normal IgA values had a Marsh 3b-c lesion and 1892 (64.9%) had t-TGA Immunoglobulin A (IgA) ≥ 10 times upper limit of normal (ULN). There is a statistically significant association between t-TGA IgA levels and the degree of mucosal damage ( P < 0.001), the higher the t-TGA IgA levels the more severe the mucosal damage. Those patients who reported symptoms had more severe mucosal damage ( P = 0.001). On the contrary, there was a negative association between age and changes of the intestinal mucosa ( P < 0.001). No association was found with gender. Regarding the IgA-deficient patients, 47.4% (18 cases) had t-TGA Immunoglobulin A (IgA) ≥ 10 times ULN and a Marsh 3b-c lesion was observed in 68.4% (26 patients). No statistical relation was found between t-TGA IgG levels and the changes of the intestinal mucosa, neither a relation with age, gender, or symptoms. CONCLUSIONS: There is a positive correlation between t-TGA IgA levels and the severity of changes of the intestinal mucosa. Such correlation was not found in IgA-deficient patients who had positive t-TGA IgG serology. The results in this group of patients support the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition recommendations about the need of performing a SBB in IgA-deficient individuals despite high t-TGA IgG levels.