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Journal of Nuclear Medicine : Official... Aug 2021
Topics: Fluorodeoxyglucose F18; Humans; Inflammation; Middle Aged; Positron-Emission Tomography
PubMed: 33893189
DOI: 10.2967/jnumed.121.262446 -
European Journal of Nuclear Medicine... Jun 2023Partial volume effect (PVE) is a consequence of the limited spatial resolution of PET scanners. PVE can cause the intensity values of a particular voxel to be...
PURPOSE
Partial volume effect (PVE) is a consequence of the limited spatial resolution of PET scanners. PVE can cause the intensity values of a particular voxel to be underestimated or overestimated due to the effect of surrounding tracer uptake. We propose a novel partial volume correction (PVC) technique to overcome the adverse effects of PVE on PET images.
METHODS
Two hundred and twelve clinical brain PET scans, including 50 F-Fluorodeoxyglucose (F-FDG), 50 F-Flortaucipir, 36 F-Flutemetamol, and 76 F-FluoroDOPA, and their corresponding T1-weighted MR images were enrolled in this study. The Iterative Yang technique was used for PVC as a reference or surrogate of the ground truth for evaluation. A cycle-consistent adversarial network (CycleGAN) was trained to directly map non-PVC PET images to PVC PET images. Quantitative analysis using various metrics, including structural similarity index (SSIM), root mean squared error (RMSE), and peak signal-to-noise ratio (PSNR), was performed. Furthermore, voxel-wise and region-wise-based correlations of activity concentration between the predicted and reference images were evaluated through joint histogram and Bland and Altman analysis. In addition, radiomic analysis was performed by calculating 20 radiomic features within 83 brain regions. Finally, a voxel-wise two-sample t-test was used to compare the predicted PVC PET images with reference PVC images for each radiotracer.
RESULTS
The Bland and Altman analysis showed the largest and smallest variance for F-FDG (95% CI: - 0.29, + 0.33 SUV, mean = 0.02 SUV) and F-Flutemetamol (95% CI: - 0.26, + 0.24 SUV, mean = - 0.01 SUV), respectively. The PSNR was lowest (29.64 ± 1.13 dB) for F-FDG and highest (36.01 ± 3.26 dB) for F-Flutemetamol. The smallest and largest SSIM were achieved for F-FDG (0.93 ± 0.01) and F-Flutemetamol (0.97 ± 0.01), respectively. The average relative error for the kurtosis radiomic feature was 3.32%, 9.39%, 4.17%, and 4.55%, while it was 4.74%, 8.80%, 7.27%, and 6.81% for NGLDM_contrast feature for F-Flutemetamol, F-FluoroDOPA, F-FDG, and F-Flortaucipir, respectively.
CONCLUSION
An end-to-end CycleGAN PVC method was developed and evaluated. Our model generates PVC images from the original non-PVC PET images without requiring additional anatomical information, such as MRI or CT. Our model eliminates the need for accurate registration or segmentation or PET scanner system response characterization. In addition, no assumptions regarding anatomical structure size, homogeneity, boundary, or background level are required.
Topics: Humans; Fluorodeoxyglucose F18; Aniline Compounds; Positron-Emission Tomography; Brain; Image Processing, Computer-Assisted
PubMed: 36808000
DOI: 10.1007/s00259-023-06152-0 -
PLoS Genetics Jul 2020Yeast and fast-growing human tumor cells share metabolic similarities in that both cells use fermentation of glucose for energy and both are highly sensitive to the...
Yeast and fast-growing human tumor cells share metabolic similarities in that both cells use fermentation of glucose for energy and both are highly sensitive to the glucose analog 2-deoxyglucose. Spontaneous mutations in S. cerevisiae that conferred resistance to 2-deoxyglucose were identified by whole genome sequencing. Missense alleles of the HXK2, REG1, GLC7 and SNF1 genes were shown to confer significant resistance to 2-deoxyglucose and all had the potential to alter the activity and or target selection of the Snf1 kinase signaling pathway. All three missense alleles in HXK2 resulted in significantly reduced catalytic activity. Addition of 2DG promotes endocytosis of the glucose transporter Hxt3. All but one of the 2DG-resistant strains reduced the 2DG-mediated hexose transporter endocytosis by increasing plasma membrane occupancy of the Hxt3 protein. Increased expression of the DOG (deoxyglucose) phosphatases has been associated with resistance to 2-deoxyglucose. Expression of both the DOG1 and DOG2 mRNA was elevated after treatment with 2-deoxyglucose but induction of these genes is not associated with 2DG-resistance. RNAseq analysis of the transcriptional response to 2DG showed large scale, genome-wide changes in mRNA abundance that were greatly reduced in the 2DG resistant strains. These findings suggest the common adaptive response to 2DG is to limit the magnitude of the response. Genetic studies of 2DG resistance using the dominant SNF1-G53R allele in cells that are genetically compromised in both the endocytosis and DOG pathways suggest that at least one more mechanism for conferring resistance to this glucose analog remains to be discovered.
Topics: Deoxyglucose; Endocytosis; Energy Metabolism; Gene Expression Regulation, Fungal; Glucose; Glucose Transport Proteins, Facilitative; Hexokinase; Humans; Mutation; Phosphoric Monoester Hydrolases; Protein Phosphatase 1; Protein Serine-Threonine Kinases; RNA, Messenger; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Signal Transduction; Whole Genome Sequencing
PubMed: 32673313
DOI: 10.1371/journal.pgen.1008484 -
Internal Medicine (Tokyo, Japan) Jun 2023
Topics: Humans; Neurolymphomatosis; Ultrasonography; Positron Emission Tomography Computed Tomography; Fluorodeoxyglucose F18
PubMed: 36351579
DOI: 10.2169/internalmedicine.0513-22 -
Biomedicine & Pharmacotherapy =... Sep 2019Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show F-FDG activity. Caution in the interpretation must be... (Review)
Review
Sites of infection and inflammation can be misleading in oncology PET/CT imaging because these areas commonly show F-FDG activity. Caution in the interpretation must be taken to avoid the misdiagnosis of malignancy. Utilization of both CT findings as well as patient history can help differentiate benign infectious and inflammatory processes from malignancy, although occasionally additional work-up may be required. This article discusses the mechanism of F-FDG uptake in infection and inflammation with illustrative examples.
Topics: Animals; Fluorodeoxyglucose F18; Humans; Infections; Inflammation; Neoplasms; Positron Emission Tomography Computed Tomography
PubMed: 31334700
DOI: 10.1016/j.biopha.2019.109168 -
Journal of Pharmacological Sciences Sep 2021We investigated the effect of 3-methyladenine (3MA), a class III phosphatidylinositol 3-kinase (PI3K)-blocking autophagy inhibitor, on cancer cell death induced by...
We investigated the effect of 3-methyladenine (3MA), a class III phosphatidylinositol 3-kinase (PI3K)-blocking autophagy inhibitor, on cancer cell death induced by simultaneous inhibition of glycolysis by 2-deoxyglucose (2DG) and mitochondrial respiration by rotenone. 2DG/rotenone reduced ATP levels and increased mitochondrial superoxide production, causing mitochondrial swelling and necrotic death in various cancer cell lines. 2DG/rotenone failed to increase proautophagic beclin-1 and autophagic flux in melanoma cells despite the activation of AMP-activated protein kinase (AMPK) and inhibition of mechanistic target of rapamycin complex 1 (mTORC1). 3MA, but not autophagy inhibition with other PI3K and lysosomal inhibitors, attenuated 2DG/rotenone-induced mitochondrial damage, oxidative stress, ATP depletion, and cell death, while antioxidant treatment mimicked its protective action. The protection was not mediated by autophagy upregulation via class I PI3K/Akt inhibition, as it was preserved in cells with genetically inhibited autophagy. 3MA increased AMPK and mTORC1 activation in energy-stressed cells, but neither AMPK nor mTORC1 inhibition reduced its cytoprotective effect. 3MA reduced JNK activation, and JNK pharmacological/genetic suppression mimicked its mitochondria-preserving and cytoprotective activity. Therefore, 3MA prevents energy stress-triggered cancer cell death through autophagy-independent mechanisms possibly involving JNK suppression and decrease of oxidative stress. Our results warrant caution when using 3MA as an autophagy inhibitor.
Topics: AMP-Activated Protein Kinases; Adenine; Animals; Autophagy; Cell Death; Deoxyglucose; JNK Mitogen-Activated Protein Kinases; Mechanistic Target of Rapamycin Complex 1; Melanoma; Melanoma, Experimental; Mice, Inbred C57BL; Mitochondria; Mitochondrial Swelling; Necrosis; Oxidative Stress; Phosphatidylinositol 3-Kinases; Rotenone; Mice
PubMed: 34294367
DOI: 10.1016/j.jphs.2021.06.003 -
Clinical Nuclear Medicine Dec 2023A 51-year-old woman with a history of IgA nephropathy was found to have a mass in the right lobe of the liver by abdominal ultrasound. The PET/CT scan revealed elevated...
A 51-year-old woman with a history of IgA nephropathy was found to have a mass in the right lobe of the liver by abdominal ultrasound. The PET/CT scan revealed elevated 68 Ga-FAPI-04 uptake in the aforementioned lesion, indicating the potential presence of liver cancer. However, subsequent histopathological analysis confirmed it to be an arteriovenous malformation. This case illustrates that 68 Ga-FAPI-04 uptake can occur in arteriovenous malformation and is a benign cause of 68 Ga-FAPI-04 uptake.
Topics: Female; Humans; Middle Aged; Glomerulonephritis, IGA; Positron Emission Tomography Computed Tomography; Arteriovenous Malformations; Quinolines; Fluorodeoxyglucose F18
PubMed: 37883057
DOI: 10.1097/RLU.0000000000004887 -
Updates in Surgery Oct 2022Recent advances in the field of tissue regeneration are offering promising therapeutic options for the treatment of short bowel syndrome. This study aimed to evaluate...
Recent advances in the field of tissue regeneration are offering promising therapeutic options for the treatment of short bowel syndrome. This study aimed to evaluate the glucose absorptive capacity of a neoformed intestine obtained from a biological scaffold in a rodent model and the steadiness of the engrafted segment area. Twenty-four male Sprague-Dawley rats were used for this study. Under anesthesia, a patch of biological material (2.2 × 1.5 cm) was engrafted in the anti-mesenteric border of the small bowels of 12 rats. Twelve rats were sham-operated. Animals were studied at 4, 8, and 10 months postengraftment. Functional and histological analyses were performed. The functional analysis was performed using an 18F-FDG analog as a probe and the results were acquired with an optical imager. The intensity of the fluorescent signal emitted by the neointestine was comparable with that emitted by the native intestine in all animals and was visible after injection in the preserved mesentery. The mean intestinal volume at time of engraftment and after 10 months was 4.08 cm (95% CI [3.58-4.58]) and 3.26 cm (CI 95% [3.23-3.29]), respectively, with a mean shrinkage of 17.3% (range 10.6-23.8%), without any evidence of stenosis. Morphological analysis revealed the progression of the biological material toward a neoformed intestine similar to the native intestine, especially at 8 and 10 months. In a rodent model, we demonstrated that a neointestine, obtained from a biological scaffold showed glucose absorption and a durable increase in diameter.
Topics: Animals; Fluorodeoxyglucose F18; Glucose; Intestines; Male; Rats; Rats, Sprague-Dawley; Short Bowel Syndrome
PubMed: 35050488
DOI: 10.1007/s13304-022-01241-5 -
European Journal of Nuclear Medicine... Jan 2023
Topics: Animals; Fluorodeoxyglucose F18; Milk; Photochemotherapy; Neoplasms; Goats; Cell Line, Tumor
PubMed: 36357594
DOI: 10.1007/s00259-022-06031-0 -
European Journal of Nuclear Medicine... Dec 2021
Topics: Fluorodeoxyglucose F18; Humans; Positron-Emission Tomography; Radiopharmaceuticals
PubMed: 33515054
DOI: 10.1007/s00259-021-05214-5