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PurposeThe prognostic value of the tumor-to-liver uptake ratio (TLR) from 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (18F–FDG-PET/CT) in the early stage of colorectal cancer (CRC) is unclear. Notably, some stage IIA CRC patients experience early recurrence even after curative resection and might benefit from neoadjuvant or adjuvant chemotherapy. This study aims to evaluate whether elevated TLR from 18F–FDG-PET/CT can predict poor prognosis in stage IIA CRC patients undergoing curative resection.MethodsFrom April 2010 to December 2013, 504 consecutive CRC patients with different TNM stages (I-IV) underwent 18F–FDG-PET/CT scans at the 6th Affiliated Hospital of Sun Yat-Sen University. Among the patients, 118 with stage IIA CRC who accepted preoperative 18F–FDG-PET/CT scanning and were treated with curative surgery alone were reviewed retrospectively. The maximum standardized uptake value (SUVmax) in the primary tumor, TLR, and demographic, clinical, histopathological, and laboratory data were analyzed. Receiver operating characteristic (ROC) curve, univariate and multivariate analyses were performed to identify prognostic factors associated with patient disease-free survival (DFS) and overall survival (OS).ResultsROC curve analysis demonstrated that TLR was superior to primary tumor SUVmax in predicting the risk of recurrence in stage IIA CRC. The optimal TLR cutoff was 6.2. Univariate analysis indicated that elevated TLR, tumor size, and lymphovascular/neural invasion correlated with DFS (P = 0.001, P = 0.002, and P = 0.001, respectively) and OS (P = 0.001, P = 0.003, and P < 0.001, respectively). The 1-, 3-, and 5-year DFS rates were 98.4%, 96.9%, and 96.9% for stage IIA CRC patients with lower TLR (≤6.2) versus 77.8%, 60.6%, and 60.6% for those with elevated TLR (>6.2), respectively. The 1-, 3-, and 5-year OS rates were 100.0%, 100.0%, and 98.3% for the patients with lower TLR versus 98.1%, 83.3%, and 74.3% for those with elevated TLR. Cox regression analysis showed that elevated TLR [>6.2; hazard ratio (HR): 3.109–57.463; P < 0.001] and tumor size (>4.4 cm; HR: 1.636–19.155; P = 0.006) were independent risk factors for DFS. Meanwhile, elevated TLR (>6.2; HR: 1.398–84.945; P = 0.023) and lymphovascular/neural invasion (positive; HR: 1.278–12.777; P = 0.017) were independent risk factors for OS.ConclusionElevated TLR predicted worse DFS and OS for stage IIA CRC patients and might serve as a potential radiological index to identify candidates for neoadjuvant or adjuvant chemotherapy. Stage IIA CRC patients with elevated TLR should be monitored carefully for early detection of possible recurrence.

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presence of Botryococcus braunii telalginite. The abundance of lycopane and its aromatised diagenetic analogues confirmed the presence of this algal species. Generally low concentrations of gammacerane and high pristane/phytane ratios indicate a low salinity, hydrologically open environment in which oxic conditions generally prevailed, resulting in relatively poor preservation of OM.Sediments of poor source rock quality deposited in the marginal fan-delta setting (the Shu-Du area) can be distinguished visually by the presence of terrigenous particles (vitrinite, inertinite and terrigenous liptinites), and geochemically by the presence of phenols in the pyrolysates.

Background: Secondary hyperparathyroidism (SHPT) usually requires parathyroidectomy when drug regimens fail. However, obtaining an exact preoperative map of the locations of the parathyroid glands is a challenge. The purpose of this study was to compare the diagnostic performance of US, dual-phase 99m Tc-MIBI scintigraphy, early and delayed 99m Tc-MIBI SPECT/CT in patients with SHPT. Methods: Sixty patients with SHPT who were undergoing dialysis were evaluated preoperatively by US, dual-phase 99m Tc-MIBI scintigraphy, early and delayed 99m Tc-MIBI SPECT/CT. Postoperative pathology served as the gold standard. The sensitivity, specificity, and accuracy were determined for each method. Spearman correlation analysis was used to analyse the correlation of hyperplastic parathyroid calcification with serum alkaline phosphatase (ALP) and parathyroid hormone (PTH). Results: A total of 229 lesions in 60 patients were pathologically confirmed to be parathyroid hyperplasia, with 209 lesions in typical sites, 15 lesions in the upper mediastinum and 5 lesions in the thyroid. A total of 88.33% (53/60) of patients had four lesions. US, early and delayed 99m Tc-MIBI SPECT/CT had significantly higher sensitivity and accuracy than dual-phase 99m Tc-MIBI scintigraphy (P < 0.001). Furthermore, early 99m Tc-MIBI SPECT/CT had significantly higher sensitivity (P < 0.001) and accuracy (P = 0.001 and P < 0.001) than US and delayed 99m Tc-MIBI SPECT/CT. In patients with ectopic hyperplastic parathyroid glands, the sensitivity of early 99m Tc-MIBI SPECT/CT (90%) was significantly higher than that of US (55%) and dual-phase 99m Tc-MIBI scintigraphy (50%) (P < 0.05). The Spearman correlation results showed a significant albeit weak association between calcification and both serum PTH and ALP (P = 0.002).

Cardiomyocyte apoptosis has been observed in several cardiovascular diseases and contributes to the subsequent cardiac remodeling processes and progression to heart failure. Consequently, apoptosis imaging is helpful for noninvasively detecting the disease progression and providing treatment guidance. Here, we tested F-labeled 2-(5-fluoropentyl)-2-methyl-malonic acid (F-ML-10) and F-labeled 2-(3-fluoropropyl)-2-methyl-malonic acid (F-ML-8) for apoptosis imaging in rat models of myocardial infarction (MI) and compared them with F-fluorodeoxyglucose (F-FDG). MI was induced in Sprague-Dawley rats by permanent left coronary artery ligation. Procedural success was confirmed by echocardiography and positron emission tomography (PET) imaging with F-FDG. In vivo PET imaging withF-ML-10 and F-ML-8 was performed in the MI models at different time points after operation. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays and immunohistochemical analyses were used to evaluate myocardial apoptosis. In vitro cell binding assays were performed to validateF-ML-8 binding to apoptotic cardiomyocytes. PET imaging demonstrated high F-ML-10 andF-ML-8 uptake where F-FDG uptake was absent. The focal accumulation of the two tracers was high on days 1 and 3 but was not notable on days 5 and 7 after surgery. The infarct-to-lung uptake ratio was 4.29 ± 0.30 forF-ML-10 and 3.51 ± 0.18 for F-ML-8 (n = 6, analyzed by averaging the uptake ratios on postoperative days 1 and 3, P< 0.05). The TUNEL results showed that myocardial cell apoptosis was closely related to the focal uptake of the apoptotic tracers in the infarct area. In addition, the apoptosis rates calculated from the TUNEL results were better correlated with F-ML-8 uptake than withF-ML-10 uptake. Ex vivo cell binding assays demonstrated that F-ML-8 accumulated in apoptotic cells but not in necrotic or normal cells. PET imaging usingF-ML-10 or F-ML-8 allows the noninvasive detection of myocardial apoptosis in the early phase. In addition,F-ML-8 may be better than F-ML-10 for apoptosis imaging. We propose that PET imaging withF-ML-10 or F-ML-8 combined withF-FDG is an alternative for detecting and assessing MI.

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Purpose 18 F-labeled amino acids (AAs) as tumor-speci c imaging agents play a critical role in hepatocellular carcinoma (HCC) imaging. In this work, we evaluated the synthesis and biological properties of a simple 18 F-labeled glutamate analogue, [ 18 F]AlF-1,4,7-triazacyclononane-1,4,7-triaceticacid-2-S-(4-isothiocyanatobenzyl))-l-glutamate ([ 18 F]AlF-NOTA-NSC-GLU) for HCC imaging via one-step reaction sequence. Methods [ 18 F]AlF-NOTA-NSC-GLU was synthesized via the one-step reaction sequence from NOTA-NSC-GLU. In order to investigate the imaging value of [ 18 F]AlF-NOTA-NSC-GLU in HCC, we conducted PET/CT imaging and competitive binding of [ 18 F]AlF-NOTA-NSC-GLU in human Hep3B tumor-bearing mice. The transport mechanism of [ 18 F]AlF-NOTA-NSC-GLU was determined by competitive inhibition and protein incorporation experiments in vitro. Results [ 18 F]AlF-NOTA-NSC-GLU was prepared without decay-corrected radiochemical yield of 29.3 ± 5.6% (n=10) within 20 min. In vitro competitive inhibition experiments demonstrated that Na +-dependent Systems X AG-, B0 + , ASC and minor X C were involved in the uptake of [ 18 F]AlF-NOTA-NSC-GLU, with Na +dependent System X AG possibly playing a more dominant role. Protein incorporation studies of the Hep3B human hepatoma cell line found almost no protein incorporation. Micro-PET/CT imaging with [ 18 F]AlF-NOTA-NSC-GLU showed good tumor-to-background contrast in Hep3B human hepatoma-bearing mouse models. After [ 18 F]AlF-NOTA-NSC-GLU injection, the tumor-to-liver uptake ratio of [ 18 F]AlF-NOTA-NSC-GLU was 2.06 ± 0.17 at 30 min post-injection. In vivo competitive binding experiments exhibited that the tumor-to-liver uptake ratio decreased by the addition of the inhibitors to block the system X AG-. Conclusion We have successfully synthesized [ 18 F]AlF-NOTA-NSC-GLU as a novel PET tracer with good radiochemical yield and high radiochemical purity. Our ndings indicate that [ 18 F]AlF-NOTA-NSC-GLU might have good clinical potential as a PET tumor-detecting agent for HCC imaging.