scholarly journals T2-weighted MRI signal predicts hormone and tumor responses to somatostatin analogs in acromegaly

2016 ◽  
Vol 23 (11) ◽  
pp. 871-881 ◽  
Author(s):  
Iulia Potorac ◽  
Patrick Petrossians ◽  
Adrian F Daly ◽  
Orsalia Alexopoulou ◽  
Sophie Borot ◽  
...  
Keyword(s):  
Multicenter Study ◽  
Signal Intensity ◽  
Treatment Duration ◽  
Large Population ◽  
Somatostatin Analogs ◽  
Subsequent Treatment ◽  
Tumor Shrinkage ◽  
Predictive Tool ◽  
Mri Sequences ◽  
The Relationship

GH-secreting pituitary adenomas can be hypo-, iso- or hyper-intense on T2-weighted MRI sequences. We conducted the current multicenter study in a large population of patients with acromegaly to analyze the relationship between T2-weighted signal intensity on diagnostic MRI and hormonal and tumoral responses to somatostatin analogs (SSA) as primary monotherapy. Acromegaly patients receiving primary SSA for at least 3 months were included in the study. Hormonal, clinical and general MRI assessments were performed and assessed centrally. We included 120 patients with acromegaly. At diagnosis, 84, 17 and 19 tumors were T2-hypo-, iso- and hyper-intense, respectively. SSA treatment duration, cumulative and mean monthly doses were similar in the three groups. Patients with T2-hypo-intense adenomas had median SSA-induced decreases in GH and IGF-1 of 88% and 59% respectively, which were significantly greater than the decreases observed in the T2-iso- and hyper-intense groups (P < 0.001). Tumor shrinkage on SSA was also significantly greater in the T2-hypo-intense group (38%) compared with the T2-iso- and hyper-intense groups (8% and 3%, respectively;P < 0.0001). The response to SSA correlated with the calculated T2 intensity: the lower the T2-weighted intensity, the greater the decrease in random GH (P < 0.0001,r = 0.22), IGF-1 (P < 0.0001,r = 0.14) and adenoma volume (P < 0.0001,r = 0.33). The T2-weighted signal intensity of GH-secreting adenomas at diagnosis correlates with hormone reduction and tumor shrinkage in response to primary SSA treatment in acromegaly. This study supports its use as a generally available predictive tool at diagnosis that could help to guide subsequent treatment choices in acromegaly.

scholarly journals T2-signal intensity, SSTR expression, and somatostatin analogs efficacy predict response to pasireotide in acromegaly

2020 ◽  
Vol 182 (6) ◽  
pp. 595-605
Author(s):  
Eva C Coopmans ◽  
Joppe J Schneiders ◽  
Nour El-Sayed ◽  
Nicole S Erler ◽  
Leo J Hofland ◽  
...  
Keyword(s):  
Signal Intensity ◽  
First Generation ◽  
Somatostatin Receptor ◽  
Somatostatin Analogs ◽  
Therapy Response ◽  
Receptor Expression ◽  
Tumor Shrinkage ◽  
Somatostatin Receptor Ligands ◽  
Tumor Volume Reduction ◽  
Long Acting

Objective T2-signal intensity and somatostatin (SST) receptor expression are recognized predictors of therapy response in acromegaly. We investigated the relationship between these predictors and the hormonal and tumoral responses to long-acting pasireotide (PAS-LAR) therapy, which were also compared with responsiveness to first-generation somatostatin receptor ligands (SRLs). Design The PAPE study is a cohort study. Methods We included 45 acromegaly patients initially receiving SRLs, followed by combination therapy with pegvisomant, and finally PAS-LAR. We assessed tumor volume reduction (≥25% from baseline), IGF-1 levels (expressed as the upper limit of normal), and T2-weighted MRI signal and SST receptor expression of the adenoma. Results Patients with significant tumor shrinkage during PAS-LAR showed higher IGF-1 levels during PAS-LAR (mean (S.D.): 1.36 (0.53) vs 0.93 (0.43), P = 0.020), less IGF-1 reduction after first-generation SRLs (mean (S.D.): 0.55 (0.71) vs 1.25 (1.07), P = 0.028), and lower SST2 receptor expression (median (IQR): 2.0 (1.0–6.0) vs 12.0 (7.5–12.0), P = 0.040). Overall, T2-signal intensity ratio was increased compared with baseline (mean (S.D.): 1.39 (0.56) vs 1.25 (0.52), P = 0.017) and a higher T2-signal was associated with lower IGF-1 levels during PAS-LAR (β: −0.29, 95% CI: −0.56 to −0.01, P = 0.045). A subset of PAS-LAR treated patients with increased T2-signal intensity achieved greater reduction of IGF-1 (mean (S.D.): 0.80 (0.60) vs 0.45 (0.39), P = 0.016). Conclusions Patients unresponsive to SRLs with a lower SST2 receptor expression are more prone to achieve tumor shrinkage during PAS-LAR. Surprisingly, tumor shrinkage is not accompanied by a biochemical response, which is accompanied with a higher T2-signal intensity.

scholarly journals Pituitary MRI characteristics in 297 acromegaly patients based on T2-weighted sequences

2015 ◽  
Vol 22 (2) ◽  
pp. 169-177 ◽  
Author(s):  
Iulia Potorac ◽  
Patrick Petrossians ◽  
Adrian F Daly ◽  
Franck Schillo ◽  
Claude Ben Slama ◽  
...  
Keyword(s):  
Large Population ◽  
Optic Chiasm ◽  
Research Priority ◽  
Maximal Diameter ◽  
Magnetic Resonance Imaging Mri ◽  
Multimodal Management ◽  
Mri Characteristics ◽  
Weighted Sequences ◽  
The Relationship

Responses of GH-secreting adenomas to multimodal management of acromegaly vary widely between patients. Understanding the behavioral patterns of GH-secreting adenomas by identifying factors predictive of their evolution is a research priority. The aim of this study was to clarify the relationship between the T2-weighted adenoma signal on diagnostic magnetic resonance imaging (MRI) in acromegaly and clinical and biological features at diagnosis. An international, multicenter, retrospective analysis was performed using a large population of 297 acromegalic patients recently diagnosed with available diagnostic MRI evaluations. The study was conducted at ten endocrine tertiary referral centers. Clinical and biochemical characteristics, and MRI signal findings were evaluated. T2-hypointense adenomas represented 52.9% of the series, were smaller than their T2-hyperintense and isointense counterparts (P<0.0001), were associated with higher IGF1 levels (P=0.0001), invaded the cavernous sinus less frequently (P=0.0002), and rarely caused optic chiasm compression (P<0.0001). Acromegalic men tended to be younger at diagnosis than women (P=0.067) and presented higher IGF1 values (P=0.01). Although in total, adenomas had a predominantly inferior extension in 45.8% of cases, in men this was more frequent (P<0.0001), whereas in women optic chiasm compression of macroadenomas occurred more often (P=0.0067). Most adenomas (45.1%) measured between 11 and 20 mm in maximal diameter and bigger adenomas were diagnosed at younger ages (P=0.0001). The T2-weighted signal differentiates GH-secreting adenomas into subgroups with particular behaviors. This raises the question of whether the T2-weighted signal could represent a factor in the classification of acromegalic patients in future studies.

scholarly journals The Relationship Between TSH and Free T4 in a Large Population Is Complex and Nonlinear and Differs by Age and Sex

2013 ◽  
Vol 98 (7) ◽  
pp. 2936-2943 ◽  
Author(s):  
Narelle C. Hadlow ◽  
Karen M. Rothacker ◽  
Robert Wardrop ◽  
Suzanne J. Brown ◽  
Ee Mun Lim ◽  
...  
Keyword(s):  
Large Population ◽  
Free T4 ◽  
The Relationship ◽  
Age And Sex

scholarly journals Handling missing MRI sequences in deep learning segmentation of brain metastases: a multicenter study

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Endre Grøvik ◽  
Darvin Yi ◽  
Michael Iv ◽  
Elizabeth Tong ◽  
Line Brennhaug Nilsen ◽  
...  
Keyword(s):  
Deep Learning ◽  
Brain Metastases ◽  
Multicenter Study ◽  
Roc Curve ◽  
Inversion Recovery ◽  
Fast Spin Echo ◽  
Operating Characteristics ◽  
Test Set ◽  
Mri Sequences ◽  
Input Level

AbstractThe purpose of this study was to assess the clinical value of a deep learning (DL) model for automatic detection and segmentation of brain metastases, in which a neural network is trained on four distinct MRI sequences using an input-level dropout layer, thus simulating the scenario of missing MRI sequences by training on the full set and all possible subsets of the input data. This retrospective, multicenter study, evaluated 165 patients with brain metastases. The proposed input-level dropout (ILD) model was trained on multisequence MRI from 100 patients and validated/tested on 10/55 patients, in which the test set was missing one of the four MRI sequences used for training. The segmentation results were compared with the performance of a state-of-the-art DeepLab V3 model. The MR sequences in the training set included pre-gadolinium and post-gadolinium (Gd) T1-weighted 3D fast spin echo, post-Gd T1-weighted inversion recovery (IR) prepped fast spoiled gradient echo, and 3D fluid attenuated inversion recovery (FLAIR), whereas the test set did not include the IR prepped image-series. The ground truth segmentations were established by experienced neuroradiologists. The results were evaluated using precision, recall, Intersection over union (IoU)-score and Dice score, and receiver operating characteristics (ROC) curve statistics, while the Wilcoxon rank sum test was used to compare the performance of the two neural networks. The area under the ROC curve (AUC), averaged across all test cases, was 0.989 ± 0.029 for the ILD-model and 0.989 ± 0.023 for the DeepLab V3 model (p = 0.62). The ILD-model showed a significantly higher Dice score (0.795 ± 0.104 vs. 0.774 ± 0.104, p = 0.017), and IoU-score (0.561 ± 0.225 vs. 0.492 ± 0.186, p < 0.001) compared to the DeepLab V3 model, and a significantly lower average false positive rate of 3.6/patient vs. 7.0/patient (p < 0.001) using a 10 mm3 lesion-size limit. The ILD-model, trained on all possible combinations of four MRI sequences, may facilitate accurate detection and segmentation of brain metastases on a multicenter basis, even when the test cohort is missing input MRI sequences.

scholarly journals The relationship between apathy and impulsivity in large population samples

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pierre Petitet ◽  
Jacqueline Scholl ◽  
Bahaaeddin Attaallah ◽  
Daniel Drew ◽  
Sanjay Manohar ◽  
...  
Keyword(s):  
Young Adults ◽  
Large Population ◽  
Assessment Tools ◽  
Self Assessment ◽  
Social And Emotional ◽  
Scale Scores ◽  
Recent Addition ◽  
The Relationship ◽  
Gathering Data ◽  
Neuropsychiatric Conditions

AbstractApathy and impulsivity are debilitating conditions associated with many neuropsychiatric conditions, and expressed to variable degrees in healthy people. While some theories suggest that they lie at different ends of a continuum, others suggest their possible co-existence. Surprisingly little is known, however, about their empirical association in the general population. Here, gathering data from six large studies ($$n = 3755$$ n = 3755 ), we investigated the relationship between measures of apathy and impulsivity in young adults. The questionnaires included commonly used self-assessment tools—Apathy Evaluation Scale, Barratt Impulsiveness Scale (BIS-11) and UPPS-P Scale—as well as a more recent addition, the Apathy Motivation Index (AMI). Remarkably, across datasets and assessment tools, global measures of apathy and impulsivity correlated positively. However, analysis of sub-scale scores revealed a more complex relationship. Although most dimensions correlated positively with one another, there were two important exceptions revealed using the AMI scale. Social apathy was mostly negatively correlated with impulsive behaviour, and emotional apathy was orthogonal to all other sub-domains. These results suggest that at a global level, apathy and impulsivity do not exist at distinct ends of a continuum. Instead, paradoxically, they most often co-exist in young adults. Processes underlying social and emotional apathy, however, appear to be different and dissociable from behavioural apathy and impulsivity.

Field Assisted Sintering Technology (FAST) Model for Prediction of Final Properties

2010 ◽  
Author(s):  
Rajiv Paul ◽  
Anil K. Kulkarni ◽  
Jogender Singh
Keyword(s):  
Electrical Breakdown ◽  
Extensive Literature ◽  
Heating Rates ◽  
Predictive Tool ◽  
Simultaneous Application ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Data Points ◽  
Field Assisted Sintering ◽  
The Relationship

Sintering is the process of making materials from powder form by heating the powder below its melting point until the particles fuse to each other. Field assisted sintering technology (FAST), also sometimes known as spark plasma sintering (SPS), uses a pulsed and/or continuous electric current along with the simultaneous application of compressive pressure which leads to extremely high heating rates and short processing durations. A high relative density and small grain size promote superior properties such as greater hardness and electrical breakdown. Hence, selection of the proper sintering parameters is of paramount importance and a predictive model would be extremely useful in narrowing the range of experimental parameters. This will drastically reduce the number of extra attempts at obtaining certain properties in a material and save experimentation time, effort and material to name a few. Four of the most important FAST parameters: target temperature, holding time, heating rate and initial particle size, have been reviewed to assess their effect on the densification, hardening and grain growth of Alumina, Copper, Silicon Carbide, Tungsten and Tungsten Carbide through extensive literature survey. The relationship between each has been incorporated in a Microsoft Excel program which acts as a predictive tool to determine an estimate of the final properties based on the initial parameters chosen. This is done by curve fitting a polynomial onto the existing data points as closely as possible and using the polynomial to obtain final properties as a function of the initial parameters. The model was verified against an existing paper which sought to obtain the optimum sintering parameters for Copper. While the actual experimentation range was 400°C to 800°C, the program would have suggested a much narrower range from 650°C to 800°C and hence saved unnecessary additional efforts.

scholarly journals High serum non-high-density lipoprotein and the risk of ischemic stroke: A systematic review

2021 ◽  
Vol 20 (1) ◽  
pp. 15-20
Author(s):  
Nyoman Tyas Apsari ◽  
◽  
Kumara Tini ◽  
I Putu Eka Widyadharma ◽  
◽  
...  
Keyword(s):  
Systematic Review ◽  
Ischemic Stroke ◽  
High Density Lipoprotein ◽  
Large Population ◽  
Density Lipoprotein ◽  
High Serum ◽  
High Density ◽  
Inclusion Criteria ◽  
Increased Risk ◽  
The Relationship

Objectives. High levels of non high density lipoprotein cholesterol (non-HDL-C) are known to contribute to an increased risk of ischemic stroke. This systematic review was conducted to identify the relationship between high non-HDL-C levels and the risk of ischemic stroke. Material and methods. This systematic review using PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement guideline, with a pre-determined search strategy. The search was conducted in Pubmed Central (PMC) and Pubmed from 2009 until 2020 with inclusion criteria, patients with a diagnosis of ischemic stroke, age >18 years, with non-HDL-C levels. The title and abstract of these articles were reviewed for relevance, based on inclusion criteria. This systematic review using STROBE to evaluate the quality in individual study which consists of 22 domains. Results. In the final stage, this systematic review identifies six cohort study consisting 166.720 participants. Overall, the quality in individual studies based on STROBE is good. We reported that there are two studies report that high non-HDL-C levels can significantly increase the risk of ischemic stroke. Meanwhile, there are four studies that report there was no significant relationship between high non-HDL-C levels and the risk of ischemic stroke. Conclusions. Overall, this systematic review provides the result about relationship between high levels of nonHDL-C and the risk of ischemic stroke, there are two studies with a larger population support that high levels of non-HDL-C can increase the risk of ischemic stroke. However, further studies is needed with a large population that specifically identify the relationship between non-HDL-C levels and risk of ischemic stroke and makes a better adjustments for confounding variables.

scholarly journals Utility of Red Tide (Karenia brevis) Monitoring Data as a Predictive Tool to Estimate Brevetoxin Accumulation in Live, Free-Ranging Marine Mammals

2021 ◽  
Vol 8 ◽  
Author(s):  
Spencer E. Fire ◽  
Glenn A. Miller ◽  
Edna R. Sabater ◽  
Randall S. Wells
Keyword(s):  
Bottlenose Dolphins ◽  
Karenia Brevis ◽  
Alternative Methods ◽  
Health Impacts ◽  
Sample Type ◽  
Red Tides ◽  
Predictive Tool ◽  
Cell Abundance ◽  
Free Ranging ◽  
The Relationship

Exposure of common bottlenose dolphins (Tursiops truncatus) to brevetoxins (PbTx) produced by blooms of the toxic phytoplankton Karenia brevis frequently results in severe health impacts, including illness and large-scale mortality events. Although PbTx accumulation in dead-stranded dolphins is well documented, there are limited data for corresponding brevetoxin exposure in live dolphins. In addition, the severity of impacts on living survivors of such toxic blooms is difficult to assess due to a lack of data on the relationship between K. brevis bloom severity and corresponding PbTx concentrations in exposed animals. Here we present results of PbTx analysis of urine, serum, milk, gastric fluid, and feces samples collected from live, free-ranging dolphins (n = 253) from Sarasota Bay, Florida during 2000–2018, and investigate the relationship between PbTx concentrations detected and corresponding K. brevis cell abundances that are temporally (within 30 days) and spatially (within 16 km) associated with each individual. We found that 28% of dolphins were associated with elevated K. brevis abundances (10,000–60,000,000 cells/L), with 41% (n = 104) of dolphins testing positive for PbTx in at least one sample type. The proportion of PbTx-positive animals was significantly greater in animals exposed to elevated cell abundances vs. those exposed to background cell abundances (&lt;10,000 cells/L), with 60 and 34% testing positive, respectively (p &lt; 0.001). PbTx was detected most frequently in feces (57%, n = 38), followed by gastric (35%, n = 37), urine (32%, n = 55), and blood (7%, n = 17). PbTx concentrations by sample type were highest in feces (2–231 ng/g; mean 46), followed by urine (0.8–90 ng/g; mean 7.2), gastric (0.8–61 ng/g; mean 12), and blood (0.3–5 ng/g; mean 1.3). Regression analyses of K. brevis cell abundance as an index of exposure vs. corresponding PbTx concentration found no statistically significant relationship for feces (p = 0.120), gastric (p = 0.349), urine (p = 0.053), or blood (p = 0.729) samples. PbTx concentrations typically ranged over two orders of magnitude between minimum and maximum values and did not scale with corresponding indices of exposure, which ranged over three orders of magnitude or more. Our results indicate that K. brevis cell abundance alone is a poor predictor of brevetoxin accumulation in bottlenose dolphins, and suggest that alternative methods (e.g., endocrine or immunological biomarkers) should be investigated as more appropriate methods for determining the severity of health impacts due to red tides.

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