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Background. Urachal carcinoma is a rare urological malignancy. Use of 18F-FDG PET/CT in urological oncology has developed slowly because of the urinary elimination of 18F-FDG. We investigated whether delayed postdiuretic 18F-FDG PET/CT could be used for diagnosing urachal carcinoma. Methods. This retrospective study included 6 patients who underwent delayed postdiuretic 18F-FDG PET/CT for the evaluation of urachal carcinoma. The delayed postdiuretic PET/CT parameters and clinical characteristics of urachal carcinoma were investigated. Results. There was no significant difference in the SUVmax between the primary tumors and the urine in the bladder before delayed diuresis (25.4 ± 19.5 vs. 42.9 ± 31.1, P = 0.18). However, the SUVmax of the primary tumors was significantly higher than the SUVmax of urine after delayed diuresis (25.4 ± 19.5 vs. 3.5 ± 1.6, P = 0.002). Diuretic 18F-FDG PET/CT was positive in all patients when compared with normal liver tissues or urine after delayed diuresis. The SUVmax, TLR, and TUR of the primary tumors were 25.4 (range: 7.2–58.9), 7.0 (range: 1.8–14.7), and 6.8 (range: 3.8–11.3), respectively. Delayed postdiuretic 18F-FDG PET/CT had a negative predictive value of 100% (5/5) for predicting lymph node metastasis. One patient received chemotherapy after radical resection of urachal carcinoma because 18F-FDG PET/CT found lung metastases, and one patient only received chemotherapy because PET/CT found peritoneal and skeletal metastases. Conclusions. Delayed postdiuretic 18F-FDG PET/CT is a useful tool for the preoperative evaluation of urachal carcinoma. 18F-FDG PET/CT may improve clinical decision making and management of urachal carcinomas. [ABSTRACT FROM AUTHOR]

What is known and objective: Several Caucasian cohort studies have associated at least one loss‐of‐function CYP2C19 on Clopidogrel (LoF‐Clopidogrel) with major adverse cardiovascular events (MACE), and only a couple have used Clinical Pharmacogenetics Implementation Consortium (CPIC®) phenotype grouping to study the associations. We primarily aimed to study the impact of use of platelet reactivity testing to escalate antiplatelet therapy and secondarily to study the association of CPIC phenotype with MACE outcomes in South‐East Asian Acute Coronary Syndrome (ACS) subjects. Method: A retrospective genotype study was performed on 238 percutaneous coronary intervention subjects, originally planned for escalation of antiplatelets using platelet reactivity testing. Results and discussion: There was no difference in MACE between the switched and unswitched groups; however, 'all bleeds' and 'clinically significant bleeds' (CSB) were statistically higher in the patients who were switched to prasugrel. The subgroup of patients who remained on clopidogrel (n = 199) were analysed using phenotype categories and MACE. Eleven percent (11.4%) of CYP2C19 poor metabolizers (PM) suffered MACE, compared with 1.3% of extensive metabolizers (EM). LoF‐Clopidogrel patients are significantly more likely to experience MACE compared with non‐LoF subjects (8.0% vs 5.4%, P:.041). What is new and conclusion: In our multivariate analysis, LoF‐Clopidogrel, malay ethnicity, diabetics and use of proton pump inhibitors were independent predictors of MACE. There were numerically more bleeds in LoF subjects who were on prasugrel compared with Clopidogrel (23.5% vs 11%, P =.082). Our data corroborate with current findings on platelet reactivity testing, suggesting that the assay would not be sensitive enough to pick up sufficient 'at‐risk' subjects as compared to the use of CYP2C19 genotyping. [ABSTRACT FROM AUTHOR]

The in situ stress has an important influence on fracture propagation and fault stability in deep formation. However, the development of oil and gas resources can only be determined according to the existing state of in situ stress in most cases. It is passive acceptance of existing in situ stress. Unfortunately, in some cases, the in situ stress conditions are not conducive to resource development. If the in situ stress can be interfered in some ways, the stress can be adjusted to a more favorable state. In order to explore the method of artificial interference, this paper established the calculation method of the in situ stress around the cracks based on fracture mechanics at first and obtained the redistribution law of the in situ stress. Based on the obtained redistribution law, attempts were made to interfere with the surrounding in situ stress by water injection in the preexisting crack. On this basis, the artificial stress intervention was applied. The results show that artificial interference of stress can effectively be achieved by water injection in the fracture. And changing the fluid pressure in the crack is the most effective way. By stress artificial intervention, critical pressure for water channelling in fractured reservoirs, directional propagation of cracks in hydraulic fracturing, and stress adjustment on the structural plane were applied. This study provides guidance for artificial stress intervention in the exploitation of the underground resource. [ABSTRACT FROM AUTHOR]

Purpose. To determine the relationship between fructose 1,6-bisphosphatase 1 (FBP1) expression and fluorine 18 (18F) fluorodeoxyglucose (FDG) uptake in patients with clear cell renal cell carcinoma (ccRCC), and to investigate how 18F-FDG uptake and FBP1 expression are related to tumor metabolism and tumor differentiation grade. Materials and Methods. A total of 54 patients with ccRCC underwent 18F-FDG combined positron emission tomography and computed tomography (PET/CT) before tumor resection. The maximum standardized uptake value (SUVmax) for the primary tumor was calculated from the 18F-FDG uptake. The relationship between SUVmax of primary tumor and the expression of FBP1, hexokinase 2 (HK2), and glucose transporter 1 (GLUT1) was analyzed via immunohistochemical analysis. Results. We identified an inverse relationship between FBP1 expression and SUVmax (P=0.031). SUVmax was higher in patients with high-grade ccRCC (mean, 11.6 ± 5.0) than in those with low-grade ccRCC (mean, 3.8 ± 1.6, P<0.001). FBP1 expression was significantly lower in patients with high-grade ccRCC (mean, 0.23 ± 0.1) than in those with low-grade ccRCC (mean, 0.57 ± 0.08; P=0.018). FBP1 status could be predicted with an accuracy of 66.7% when a SUVmax cutoff value of 3.55 was used. GLUT1 expression in ccRCC was positively correlated with 18F-FDG uptake and FBP1 status, whereas HK2 expression was not. Conclusion. SUVmax in patients with ccRCC is inversely associated with the expression of FBP1, and FBP1 may inhibit 18F-FDG uptake via regulating GLUT1. SUVmax is higher in patients with high-grade ccRCC than in those with low-grade ccRCC, which could be the result of lower FBP1 expression in patients with high-grade ccRCC. [ABSTRACT FROM AUTHOR]

Purpose. We evaluated the prognostic value of preoperative 18F-FDG uptake by suspected lymph nodes (LNs) using 18F-FDG PET/CT in colorectal cancer patients. Methods. Patients with CRC underwent 18F-FDG PET/CT before radical surgery. We used Cox proportional hazards regression to examine the relationship between recurrence and the 18F-FDG maximum standardized uptake value (SUVmax) in the suspected LNs (SUVLN) on 18F-FDG PET/CT. Results. Clinical data, treatment modalities, and results from 90 CR C patients were reviewed. The median follow-up was 19 months (range 3 to 72 months). Receiver operating characteristic analysis identified SUVLN 1.15 was the optimal cut-off value for predicting recurrence. SUVLN correlated with tumour size (P=0.045), lymph node metastasis (P=0.03), and recurrence (P<0.0001). Univariate analysis showed significant associations between recurrence and SUVLN (P=0.017), and tumour grade (P=0.013). Multivariate analysis identified SUVLN (P<0.0001), and tumour grade (P=0.005) as independent risk factors for recurrence. Patients with SUVLN ≤ 1.15 and SUVLN > 0.15 differed significantly in terms of recurrence (P<0.0001). Conclusion. Preoperative SUVLN measured by 18F-FDG PET/CT was significantly associated with recurrence and had significant prognostic value for recurrence-free survival in patients with colorectal cancer. [ABSTRACT FROM AUTHOR]