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Objective The utility of 18 F-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scanning and brain magnetic resonance imaging (MRI) as a staging workup for lung adenocarcinoma manifesting as pure ground glass opacity (GGO) is unknown. The purpose of this study was to determine the utility of these 2 tests for preoperative staging of pure GGO nodular lung adenocarcinoma. Methods The study included 164 patients (male:female, 73:91; mean age, 62 years) with pure GGO nodular lung adenocarcinoma who underwent PET/CT (in 136 patients) and/or brain MRI (in 109 patients) before surgery. Pathologic N staging and dedicated standard imaging or follow-up imaging findings for M staging were used as reference standards. The median follow-up time was 47.9 months. Results On PET/CT scan, abnormal FDG uptake of lymph nodes was found in 2 of 136 patients (1.5%); both were negative on final pathology. Abnormal FDG uptake of the liver was detected in 1 patient, which was also confirmed to be negative by dedicated abdominal CT. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET/CT in detecting metastases were not applicable, 98% (95% confidence interval [CI], 94%-100%), 0% (95% CI, 0%-71%), 100% (95% CI, 97%-100%), and 98% (95% CI, 94%-100%), respectively. No brain metastasis was found in preoperative brain MRI of 109 patients. Of 109 patients, 1 (0.9%) developed brain metastasis 30 months after surgical resection. Conclusions PET/CT and brain MRI is not necessary in the staging of pure GGO nodular lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Objectives This study sought to investigate the role of carotid fluoro-2-deoxyglucose (FDG) uptake as an independent prognostic indicator and to determine whether its addition improves risk prediction beyond the Framingham risk score (FRS) and carotid intima-media thickness (CIMT). Background The prognostic value of carotid FDG uptake independent of and incremental to traditional cardiovascular risk factors and CIMT in asymptomatic individuals has not been evaluated. Methods We measured carotid FDG uptake and CIMT in 1,089 asymptomatic adults (51.8 ± 6.3 years of age, 94.3% males) who underwent positron emission tomography/computed tomography imaging and examined the prognostic value of carotid FDG uptake compared with traditional risk factors and CIMT. Results Cardiocerebrovascular events occurred in 19 participants (1.74%) during an average follow-up of 4.2 years (range 1.0 to 5.5 years). Multivariable Cox proportional hazards analyses revealed that high carotid FDG uptake (hazard ratio: 2.98; 95% confidence interval: 1.17 to 7.62; p = 0.022) and high CIMT (hazard ratio: 2.82; 95% confidence interval: 1.13 to 7.03; p = 0.026) were independent predictors of events. Comparison of predictive power demonstrated that adding carotid FDG uptake, but not CIMT, to the FRS significantly increased the time-dependent area under the receiver-operating characteristic curve from 0.60 to 0.73 (p = 0.04). Furthermore, improvement approaching significance was achieved by adding carotid FDG uptake to the FRS plus CIMT, which increased the area under the receiver-operating characteristic curve from 0.65 to 0.75 (p = 0.07). Net reclassification for event prediction was similarly improved by addition of carotid FDG uptake to the FRS (net reclassification index, 40.1%; p = 0.06), as well as the FRS plus CIMT (net reclassification index, 32.9%; p = 0.07). Conclusions High carotid FDG uptake predicts cardiovascular events independent of traditional risk factors and CIMT in asymptomatic adults and may add to risk stratification beyond the FRS and CIMT. [ABSTRACT FROM AUTHOR]

Background: The major concerns in the surgical treatment of extensive or recurrent thyroid cancer include the difficulty of precise intraoperative and real-time tumor localization, the possibility of missing small metastatic lymph nodes during the operation, the need for reoperation due to recurrence, and complications. The usefulness and feasibility of an intraoperative PET probe have been reported for many other cancers; however, a standard, radioguided, operative protocol using a PET probe in thyroid cancer has not been established. The purpose of the current study was to evaluate the feasibility of an intraoperative PET probe with respect to precise tumor localization, verification of complete resection, and a decrease in unnecessary reoperations and complications. Methods: This was a prospective, controlled study. Inclusion criteria were thyroid cancer requiring a total thyroidectomy with a modified radical neck dissection (MRND) and recurrent thyroid cancer after thyroid surgery. The types of procedures included total thyroidectomy with MRND, selective neck dissection (SND), and excision of recurrent thyroid masses. The PET probe NodeSeeker® is a high-energy gamma probe seeking 511 keV photons. Operative exploration was carried out between 2 and 6 h after injection of 18F-FDG. The surgeon calculated the target-to-background ratio (T/B ratio) by checking the 10-sec accumulated count using the PET probe. We performed a re-exploration if the T/B ratio was >1.3 in the operative bed. Results: Twelve patients underwent PET probe-guided operation. SNDs, mass excisions, total thyroidectomy with MRND, and MRND were performed on 7, 4, and 1 patient, respectively. All tumors were localized by the PET probe precisely in real time, and the lesions not observed on preoperative PET were detected by the PET probe in 7 patients. Furthermore, additional lymph nodes that were not identified on preoperative ultrasonography were detected in 1 patient. The mean T/B ratio of thyroid carcinoma was 1.51 ± 0.53 (range, 1.17–4.03) and the postoperative serum thyroglobulin off thyroid hormone was <2.0 ng/ml. Conclusion: Radioguided surgery using an intraoperative PET probe in thyroid cancer appears to be a useful method for real-time tumor localization, verification of complete excision, and minimization of the possibility of residual cancer. Therefore, an intraoperative PET probe in thyroid cancer may decrease unnecessary reoperations and complications due to persistent disease. [Copyright &y& Elsevier]

Abstract: We consider a class of nonlinear time delay systems created by generalizing the model for FAST TCP, an Internet congestion control algorithm. We achieve a time delay independent sufficient condition for the global asymptotic stability of the class of systems. The sufficient condition is verified by constructing two sequences that represent the lower and upper bound variations of the system trajectory in time, and showing that the two sequences converge to the equilibrium point of the system. The simulation results exemplify that the sufficient condition is valid for global asymptotic stability, and that the sufficient condition is a close approximation to the unknown necessary and sufficient condition for global asymptotic stability. [Copyright &y& Elsevier]

Abstract: Acetylcholinesterase (AChE) has been an important cholinergic factor for the diagnosis of Alzheimer''s disease (AD), because of reduced AChE activity in the postmortem brains of AD patients. We previously developed 5,7-dihydro-3-(2-(1-(2-[18F]fluorobenzyl)-4-piperidinyl)ethyl)-6H-pyrrolo(3,2,f)-1,2-benzisoxazol-6-one (2-[18F]fluoro-CP-118,954) for in vivo studies of AChE in mice. In the present study, we automated the synthesis of 2-[18F]fluoro-CP-118,954 for the routine use and evaluated the radioligand by microPET and ex vivo Cerenkov luminescence imaging of mouse AChE. 4-[18F]Fluoro-donepezil, another AChE inhibitor, was used for comparison. Automated syntheses of 2-[18F]fluoro-CP-118,954 and 4-[18F]fluoro-donepezil resulted in high radiochemical yields (25–33% and 30–40%) and high specific activity (27.1–35.4 and 29.7–37.3 GBq/μmol). Brain microPET images of two ICR mice injected with 2-[18F]fluoro-CP-118,954 demonstrated high uptake in the striatum (ROI analysis: 5.1 %ID/g for the first 30 min and 4.1 %ID/g for another 30 min), and a blocking study with injection of CP-118,954 into one of the mice at 30 min after radioligand injection led to complete blocking of radioligand uptake in the striatum (ROI analysis: 1.9 %ID/g), whereas 18F-labeled donepezil did not show specific uptake in the striatum. In another set of experiments, the brain tissues (striatum, parietal cortex, frontal cortex and cerebellum) were excised after brain microPET/CT imaging of mouse injected with 2-[18F]fluoro-CP-118,954, and a high striatal uptake was also detected in ex vivo optical and microPET images (ROI analysis: 1.4 %ID/g) and in γ-counting data (2.1 %ID/g at 50 min post-injection) of the brain tissues. Taken together, these results demonstrated that 2-[18F]fluoro-CP-118,954 specifically binds to AChE in mouse brains. [Copyright &y& Elsevier]

Abstract: Background: Few studies assessing the functional change of each kidney following warm ischaemia after partial nephrectomy are available. Objectives: Our aim was to identify the effects of the warm ischaemic time (WIT) on renal function after partial nephrectomy under the pneumoperitoneum. Design, setting, and participants: Forty-four consecutive patients who underwent laparoscopic partial nephrectomy (LPN) or robot-assisted partial nephrectomy (RAPN) from June 2008 to May 2009 for a single cT1 renal tumour were included in this prospective protocol. Measurements: Technetium Tc 99m-diethylenetriaminepentaacetic acid (Tc 99m-DTPA) renal scintigraphy was used to determine the glomerular filtration rate (GFR) of both kidneys and each kidney individually. Tc 99m-DTPA GFR was performed preoperatively and 3 mo postoperatively. In addition, we analysed Tc 99m-DTPA scintigraphy GFR regionally in the healthy areas of the affected kidney. Results and limitations: Patients with WIT >28min had a significantly greater decrease in the GFR of the affected kidney (p =0.031). The GFR of the affected kidney showed a significant decrease perioperatively (46.4±14.3 to 37.9±11.9ml/min per 1.73 m2; p =0.003). The functional change of the nonaffected kidney showed an increasing trend (47.5±13.8 to 51.4±14.3ml/min per 1.73 m2), although it was not statistically significant (p =0.103). Regional Tc 99m-DTPA GFR of both affected kidney and nonaffected kidney showed no significant differences perioperatively (6.3±1.8 to 6.1±1.9ml/min per 1.73 m2; p =0.641; 6.6±1.9 to 7.1±2.0ml/min per 1.73 m2; p =0.200). On multivariate analysis, preoperative GFR, resected volume of marginal healthy tissue, and WIT were independent predictors for functional reduction of the affected kidney (p <0.05). The study was limited by small numbers and short follow-up periods. Conclusions: Stationary overall renal function after LPN or RAPN is masked possibly by functional compensation of the contralateral healthy kidney. The damage of the affected kidney estimated by scintigraphy occurs when WIT exceeds 28min during partial nephrectomy under the pneumoperitoneum. [Copyright &y& Elsevier]

This study presents the Quick-Connector, a new self-fastening joint system designed specifically for modular steel construction. By eliminating the need for a dedicated workspace during the connection process, the Quick-Connector minimizes disruptions to finishing work. A comprehensive set of tests, including pull-out, shear, and cyclic tests, was conducted on a full-scale prototype to evaluate its structural performance. The experimental results demonstrate that the Quick-Connector exhibits exceptional connecting performance, meeting the shear and tensile strength requirements for high-tension bolts. The seismic performance of the Quick-Connector was also evaluated through cyclic testing, highlighting its potential as a viable replacement for high-tensile bolts. Furthermore, a push-over analysis was carried out to develop an elastic structural design model specifically for buildings incorporating the Quick-Connector. The analysis results closely aligned with the experimental findings, validating the accuracy of the proposed model. Overall, the Quick-Connector offers a promising alternative to traditional bolted connections in modular construction, with the potential to enhance construction efficiency, quality, and safety. • Novel self-fastening joint system, Quick-Connector, for modular steel construction. • Elimination of separate working areas during connection process, enhancing construction efficiency. • Connecting performance evaluations of the Quick-Connectors indicate that they can replace high-strength bolts. • Validated push-over analysis model using MIDAS Gen for elastic structural design. [ABSTRACT FROM AUTHOR]

• Fertiliser drawn forward osmosis (FDFO) for urban wastewater reuse was investigated. • Applying additional pressure in the FDFO was considered as an alternative. • Pressure applied at lower than a 60-fold fertiliser dilution was recommended. • Water flux of 10 Lm−2 h-1 was required to make the FDFO economically feasible. • Pressure-assisted FDFO could be competitive with the existing water reuse facility. Pressure-assisted osmosis (PAO) has been suggested to integrate with fertiliser driven forward osmosis (FDFO) to improve the overall efficiency of simultaneous wastewater reuse and fertiliser osmotic dilution. This study aims to demonstrate the techno-economic feasibility of pressure-assisted fertiliser driven forward osmosis (PAFDO) hybrid system compared to the existing ultraviolet and reverse osmosis (UV RO) process. The results showed that coupling FDFO with PAO (i.e. PAFDO) could help fulfill the water quality required for greenwall fertigation. An economic analysis on capital and operational costs for the PAFDO showed that the PAO mode application at a lower FDFO dilution stage could significantly reduce the costs. However, when considering the different applied pressures in PAO (i.e. 2, 4, and 6 bar), the increase in the total water cost was not significant. This indicates that the dilution stage for applying PAO is more sensitive to the total water cost of the PAFDO than the applied pressure. A coupling of higher average water flux (>10 L/m2h) and lower draw solution (DS) dilution factor (DF < 60) is recommended. Therefore, this could make the PAFDO system economically viable compared to the benchmark for the UV-RO disinfection system. [ABSTRACT FROM AUTHOR]

Abstract Low energy consumption and less fouling propensity of forward osmosis (FO) processes have been attractive as a promising water filtration technology. The performance of this process is however significantly influenced by its operating conditions. Moreover, these operating parameters have both favourable and adverse effects on its performance. Therefore, it is very important to optimize its performance for efficient and economic operation. This study aims to develop a software to analyze a full-scale FO system for optimum performance. A comprehensive theoretical framework was developed to estimate the performance of FO system. Analysis results were compared with the experimental results to validate the models. About 5% deviation of simulation results and the experimental findings shows a very good agreement between them. A novel optimization algorithm was then developed to estimate the minimum required draw solution (DS) inlet flowrate and the number of elements in a pressure vessel to attain the design objectives (i.e. desired final DS concentration and recovery rate at a specific feed solution (FS) flowrate). A detailed parametric study was also conducted to determine the optimum operating conditions for different objectives. It showed that for a specific design objective, higher recovery rate can be achieved by increasing the DS flowrate and number of elements in a pressure vessel. In contrast, lower final concentration can be obtained by lowering the DS flowrate and increasing the number of elements. Finally, a MATLAB based software with graphical user interface was developed to make the analysis process easier and efficient. Graphical abstract Image 1 Highlights • Full scale numerical simulation of FO process was investigated. • A novel optimization algorithm was developed by overall performance of the system. • Four elements was found to be optimum for 50% recovery rate. • MATLAB based graphical user interface was developed for efficient full scale FO system analysis. [ABSTRACT FROM AUTHOR]

Objectives: The efficacy of radioiodine remnant ablation (RRA) for patients with differentiated thyroid carcinoma (DTC) with gross extrathyroidal extension (ETE) is well described in observational studies. However, its role in gross ETE invading only strap muscles, T3b category in the newly proposed eighth edition of the TNM staging system, is currently unknown.Methods: This study retrospectively analyzed 260 DTC patients with ETE invading only strap muscles who underwent thyroidectomy at a tertiary Korean hospital between 1994 and 2005. Cancer-specific survival (CSS) and recurrence-free survival (RFS) in the no RRA (n = 13), low RRA activity (<3.7 GBq, n = 80), and high RRA activity (≥3.7 GBq, n = 167) groups were studied.Results: No significant differences were observed between low and high activity RRA groups in terms of 10-year CSS (97.3% versus 99.3%; HR 0.23, 95% CI 0.02-2.57; p = .235) and RFS (86.8% versus 88.8%; 0.90, 0.40-2.03; p = .804). In the no RRA group, no patients died of cancer, and only one developed structural recurrence. In Cox regression analyses with inverse probability of treatment weighting adjusted for clinicopathologic risk factors, high activity RRA was not related to recurrence outcomes compared to low activity (HR 0.60, 95% CI 0.26-1.35; p = .214).Conclusions: Long term oncologic outcomes did not significantly differ between low versus high activity RRA groups, which suggests that low activity RRA might be sufficient in patients with DTC with gross ETE invading only strap muscles. Further studies are needed to clarify the optimal activity of RRA in these patients. [ABSTRACT FROM AUTHOR]

This study evaluates various options for full-scale modular configuration of forward osmosis (FO) process for osmotic dilution of seawater using wastewater for simultaneous desalination and water reuse through FO-reverse osmosis (RO) hybrid system. Empirical relationship obtained from one FO membrane element operation was used to simulate the operational performances of different FO module configurations. The main limiting criteria for module operation is to always maintain the feed pressure higher than the draw pressure throughout the housing module for safe operation without affecting membrane integrity. Experimental studies under the conditions tested in this study show that a single membrane housing cannot accommodate more than four elements as the draw pressure exceeds the feed pressure. This then indicates that a single stage housing with eight elements is not likely to be practical for safe FO operation. Hence, six different FO modular configurations were proposed and simulated. A two-stage FO configuration with multiple housings (in parallel) in the second stage using same or larger spacer thickness reduces draw pressure build-up as the draw flow rates are reduced to half in the second stage thereby allowing more than four elements in the second stage housing. The loss of feed pressure (pressure drop) and osmotic driving force in the second stage are compensated by operating under the pressure assisted osmosis (PAO) mode, which helps enhance permeate flux and maintains positive pressure differences between the feed and draw chamber. The PAO energy penalty is compensated by enhanced permeate throughput, reduced membrane area, and plant footprint. The contribution of FO/PAO to total energy consumption was not significant compared to post RO desalination (90%) indicating that the proposed two-stage FO modular configuration is one way of making the FO full-scale operation practical for FO-RO hybrid system. [ABSTRACT FROM AUTHOR]

Purpose: Vascular endothelial growth factor (VEGF) is a crucial regulator of angiogenesis. In this study, we labeled VEGF121 with 68Ga using a hydrophilic chelating agent, NODAGA and evaluated the resulting 68Ga-NODAGA-VEGF121 for in vivo imaging of VEGF receptor (VEGFR) expression. Methods: NODAGA-VEGF121 was prepared and its binding affinity for VEGFR2 was measured using 125I-VEGF121. 68Ga-NODAGA-VEGF121 was prepared by labeling NODAGA-VEGF121 with 68GaCl3 followed by purification using a PD-10 column. Human aortic endothelial cell (HAEC) binding studies of 68Ga-NODAGA-VEGF121 were performed at 37°C for 4h. MicroPET imaging followed by biodistribution studies were performed in U87MG tumor-bearing mice injected with 68Ga-NODAGA-VEGF121. Immunofluorescence staining of the tumor tissues was performed to verify VEGFR2 expression. Results: Binding affinity of NODAGA-VEGF121 for VEGFR2 was found to be comparable to that of VEGF121. 68Ga-NODAGA-VEGF121 was prepared in 47.8% yield with specific activity of 3.4GBq/mg. 68Ga-NODAGA-VEGF121 was avidly taken up by HAECs with a time-dependent increase from 9.88 %ID at 1h to 20.86 %ID at 4h. MicroPET imaging of mice demonstrated high liver and spleen uptake with clear visualization of tumor at 1h after injection. ROI analysis of tumors revealed 2.53±0.11 %ID/g at 4h after injection. In the blocking study, tumor uptake was inhibited by 29% at 4h. Subsequent biodistribution studies demonstrated tumor uptake of 2.38±0.15 %ID/g. Immunofluorescence staining of the tumor tissues displayed high level of VEGFR2 expression. Conclusions: These results demonstrate that 68Ga-NODAGA-VEGF121 led to VEGFR-specific distribution in U87MG tumor-bearing mice. This study also suggests that altered physicochemical properties of VEGF121 after radiolabeling may affect biodistribution of the radiolabeled VEGF121. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prognostic role of metabolic response by the use of serial sets of positron emission tomography/computed tomography (PET/CT) in patients with cervical cancer who were treated with concurrent chemoradiation therapy (CCRT). Methods and Materials: A total of 60 patients who were treated with CCRT between February 2009 and December 2010 were analyzed. Three sequential PET/CT images were acquired for each patient: pre-CCRT, during-CCRT at 4 weeks of CCRT, and 1 month post-CCRT PET/CT. Metabolic responses were assessed qualitatively. The percentage changes in the maximum values of standardized uptake value (ΔSUVmax%) from the PET/CT images acquired pre-CCRT and during-CCRT were calculated. Receiver operating characteristic (ROC) curve analysis was performed to evaluate whether ΔSUVmax% could predict complete response (CR) on the post-CCRT PET/CT and to identify the best cutoff value. Prognostic factors of progression-free survival (PFS) were analyzed. Results: During-CCRT PET/CT showed that 8 patients (13%) had CR, and the other 52 patients (87%) had partial response (PR). On the post-CCRT PET/CT, 43 patients (73%) had CR, 12 patients (20%) had PR, and 4 patients (7%) had progressive disease. The average SUVmax in primary tumors was 16.3 (range, 6.4-53.0) on the pre-CCRT PET/CT images and 5.3 (range, 0-19.4) on the during-CCRT PET/CT images. According to ROC curve analysis, ΔSUVmax% could predict CR response on post-CCRT PET/CT (P<.001, cutoff value of 59.7%). In all patients, the PFS rate was 71.9% at 2 years. Multivariate analysis showed that ΔSUVmax% ≥60% (P=.045) and CR response on the post-CCRT PET/CT (P=.012) were statistically significant predictors of PFS. Conclusion: Metabolic responses on the during-CCRT images at 4 weeks of treatment and 1-month post-CCRT PET/CT images may predict treatment outcomes in patients with cervical cancer. ΔSUVmax% ≥60% at 4 weeks of CCRT may predict CR response on 1-month post-CCRT PET/CT and also PFS. [Copyright &y& Elsevier]

We have developed a vascular endothelial growth factor 121 (VEGF121)-based, dual positron emission tomography (PET)/optical imaging probe for monitoring VEGF receptor (VEGFR) expression using a streptavidin (SAv)–biotin platform. 64Cu-1,4,7,10-tetraazacyclododecane-N,N′,N″,N′″-tetraacetic acid (DOTA)-conjugated Alexa Fluor 680 (AF)-SAv/biotin-PEG-VEGF121 (64Cu-labeled dual probe) was prepared with a radiochemical yield of 31.40 ± 3.30% and was stable for 24 h in serum. A human aortic endothelial cell binding study showed avid, time-dependent cellular uptake of the 64Cu-labeled dual probe. MicroPET imaging of U87MG tumor-bearing mice injected with 64Cu-labeled dual probe showed rapid, high accumulation of radioactivity in tumors, which reached 3.90 ± 0.17 %ID/g and 4.93 ± 0.80 %ID/g at 1 and 22 h after injection, respectively. Subsequent optical imaging of mice revealed strong fluorescence signals in tumors. Biodistribution studies performed after in vivo imaging demonstrated tumor uptake of 4.19 ± 0.14 %ID/g. Tumor uptake was blocked by 28% in the presence of VEGF121, confirming the VEGFR specificity of the 64Cu-labeled dual probe. Ex vivo microPET images of major tissues showed the signal intensities consistent with optical images of the corresponding tissues. Moreover, it was shown that tumor uptake of the 64Cu-labeled dual probe was not due to non-specific uptake by 64Cu-DOTA-conjugated AF-SAv (tumor uptake; 1.57 ± 0.09 %ID/g). Taken together, these results suggest that the 64Cu-labeled dual probe is a promising candidate for dual PET/optical imaging of VEGFR expression. [ABSTRACT FROM AUTHOR]

Abstract: The two-stage system of limited and extensive disease has been widely employed for small cell lung cancer (SCLC). However, the International Association for the Study of Lung Cancer has proposed that the TNM classification should be incorporated into clinical practice. The purpose of this study was to evaluate the applicability of the Union for International Cancer Control (UICC) 7th TNM staging system to SCLC. We retrospectively reviewed the medical records of consecutive patients with newly diagnosed histologically proven SCLC between March 2005 and January 2010. Patients who had other concurrent malignancies or had combined-type SCLC were excluded. We assessed overall survival (OS) according to the T descriptor, N descriptor, M descriptor, and TNM stage grouping. In total, 320 SCLC patients were included. Median age was 65 years and 286 patients (89.4%) were male. Median OS was 12.7 months. There were no significant differences in OS according to the T descriptor (P =0.880). However, there were significant differences in OS according to the N (P <0.001) and M (P <0.001) descriptors and TNM stage grouping (P <0.001). Hazard ratios for OS, adjusted for known prognostic factors, differed significantly according to the N and M descriptor, and TNM stage grouping, but not according to the T descriptors. The UICC 7th TNM staging system may contribute to a more precise prognosis in SCLC patients. Further studies are required to evaluate the applicability of the TNM staging system to SCLC. [Copyright &y& Elsevier]

Abstract: Aim: To date, no data are available on the use of PET/CT for preoperative staging of gastric cancer. We attempted to evaluate the value of PET/CT for preoperative staging of advanced gastric cancer, and to compare the use of PET/CT with contrast-enhanced CT (CECT). Materials and methods: We analyzed PET/CT of 78 patients with surgically proven advanced gastric cancer who had undergone preoperative CECT. Qualitative analysis was conducted by assessing the presence of primary tumors and metastases with PET/CT and CECT. Results: Among 71 patients who underwent a gastrectomy, 69 primary tumors (93%) were diagnosed by PET/CT, while 64 primary tumors (90%) were detected by CECT (p =0.55). For regional lymph node metastasis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT vs. CECT were 41% vs. 25% (p =0.00019), 100% vs. 92% (p =0.31), 100% vs. 98% (p =0.46), 26% vs. 42% (p =0.14), and 51% vs. 72% (p =0.00089), respectively. Conclusion: Overall, PET/CT showed comparable diagnostic performance to CECT in diagnosing primary tumors and regional lymph node metastases, though PET/CT was inferior to CECT for the sensitivity and accuracy in diagnosing regional lymph node metastases. Nevertheless, PET/CT would be useful when CECT findings were equivocal due to its high positive predictability. [Copyright &y& Elsevier]

Purpose: To evaluate the impact of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on changes in treatment plan and target definition for preoperative radiotherapy in patients with rectal cancer.Methods: Embase, PubMed, and Cochrane Library were searched up to November 2020 for all studies investigating the role of preoperative FDG PET in patients who underwent neoadjuvant radiotherapy before curative-intent surgery. The proportion of patients whose treatment plan (curative vs. palliative intent) or target definition was changed after FDG PET was analyzed. A random-effects model was used for pooled analysis. The change in target definition was compared between conventional radiological imaging-based target volume [gross tumor volume (GTV) or planning target volume (PTV)] and PET-based target volume (GTV or PTV) using the standardized mean difference (SMD) and 95% confidence interval (CI).Results: A total of 336 patients from twelve studies were included. In eight studies, PET changed either the treatment intent or target definition in 24.8% of patients (95% CI 15.1% to 37.9%, I2 = 69%). In ten studies, the PET-based GTV was lower than the conventional imaging-based target volume (SMD -7.0, 95% CI -1.39 to -0.01). However, there was no significant difference between conventional imaging-based and PET-based PTV (SMD -0.07, 95% CI -0.75 to 0.62). In six studies evaluating the initial staging based on PET, the initial staging (nodal or metastasis status) was changed in 53 of 229 patients (23.1%). Newly detected or additional distant metastases were identified in 22 patients (9.6%) after FDG PET.Conclusion: The use of FDG PET influences radiotherapy planning in a fourth of patients with rectal cancer. FDG PET can provide additive information for accurate tumor delineation, although PET-based PTV did not significantly change. These findings suggest that FDG PET may be beneficial to patients with rectal cancer before establishing a radiotherapy plan. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Spontaneous intracranial hypotension (SIH) is caused by spontaneous spinal cerebrospinal fluid (CSF) leaks. However, there is debate regarding clinical indication of radionuclide cisternography (RNC) for identification of the actual site of a CSF leak. We therefore investigated the potential value of RNC in SIH. Patients and methods: RNC was performed on 30 patients with SIH. Patients were managed with conservative management only or epidural blood patches (EBPs) according to clinical conditions and RNC findings. Results: RNC revealed direct signs of spinal CSF leaks in 80% of patients. Of this group, complete resolution of headache was obtained in 12 (71%) of 17 patients who received EBP vs. 1 (14%) of 7 patients treated with conservative management only (p =0.02). Complete headache relief with conservative management only was seen in one (14%) patient with direct signs of spinal CSF leaks compared to five (83%) patients without direct signs (p =0.03). Conclusion: RNC is useful for diagnosis and better management planning of SIH. [Copyright &y& Elsevier]

Size-controlled graphene oxide (SGO) nanosheets, which are uniform and smaller in size than 2 μm, were successfully incorporated into a polyamide (PA) layer for preparing an outer-selective hollow fiber (OSHF) thin-film nanocomposite (TFN) membrane for forward osmosis (FO) applications by vacuum-assisted interfacial polymerization (VAIP). Here, we specifically demonstrate that the SGO nanosheets in amine aqueous solution were horizontally aligned and stacked on the surface of a membrane substrate by vacuum suction from outside to inside in the VAIP; the SGO nanosheets were then well-incorporated into the thin PA layer with less physical damage. In addition, the SGO nanosheets' effective loading inside the PA layer under the VAIP was much higher than that under the typical interfacial polymerization (IP), since there is no issue about the particle loss from air or nitrogen blowing to remove excess amine solution. The benefit would be highly cost-effective in terms of the nanomaterial's use in a TFN membrane production. As a result, the optimum OSHF TFN membrane incorporated with SGO at 0.0005 wt% (SGO5) exhibited outstanding FO performance, including higher water flux at 39.0 L m-2 h-1 and lower specific reverse solute flux at 0.16 g L-1, using a 1 M NaCl draw solution. Furthermore, this study demonstrates the effect of graphene oxide (GO)'s lateral size toward the short water pathway, and GO's stable incorporation and hydrophilicity of the PA thin film. In the fouling test using artificial wastewater, SGO-incorporated membranes exhibited enhanced fouling resistance and cleaning efficiency against the foulant-rich solution. This novel TFN membrane is therefore a good candidate to address FO's challenges for wastewater treatment or desalination. Image 1 • Outer-selective hollow fiber TFN GO membrane was successfully fabricated. • GO was horizontally aligned and stacked on the substrate by the vacuum pressure. • GO loading was extremely low due to little loss of GO in the vacuum-assisted IP. • GO's lateral size in PA layer affected the water transport across the membrane. • Best GO membrane exhibited high permeability and strong fouling resistance. [ABSTRACT FROM AUTHOR]

PET and NIR images of U87MG tumor xenograft models obtained 24 h after injection of [64Cu] 1 and 3. It was previously reported that tetraiodothyroacetic acid (tetrac) inhibits angiogenesis by binding to the cell surface receptor for thyroid hormone on integrin α V β 3. Therefore, we synthesized and evaluated two 64Cu-labeled tetrac derivatives and a Cy5.5-labeled tetrac derivative for tumor angiogenesis imaging. Tetrac was structurally modified to conjugate with 1,4,7,10-tetraazacyclododecane- N,N′,N″,N″′ -tetraacetic acid (DOTA) via its hydroxy or carboxylic acid end, and the resulting DOTA-conjugated tetrac derivatives were then labeled with 64Cu. Tetrac was also conjugated with Cy5.5 via its carboxylic acid end. All three tetrac derivatives (1 – 3) exhibited greater inhibitory activity than tetrac against endothelial cell tube formation. The U87MG cell binding of [64Cu] 2 showed a time-dependent increase over 24 h and it was inhibited by 38% at 4 h in the presence of tetrac, indicating specificity of [64Cu] 2 to the thyroid hormone receptor site on integrin α V β 3. Positron emission tomography (PET) images of U87MG tumor-bearing mice injected with [64Cu] 1 and [64Cu] 2 revealed that high radioactivity accumulated in the tumors, and that the tumor uptake and tumor-to-nontarget uptake ratio were higher in small tumors than in large tumors. In addition, the Cy5.5-labeled tetrac derivative (3) displayed a strong near-infrared (NIR) signal in the tumors. Taken together, these results suggest that these ligands hold promise as imaging agents for visualization of tumor angiogenesis. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the feasibility of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT)-guided conformal brachytherapy treatment planning in patients with cervical cancer. Methods and Materials: Pretreatment FDG-PET/CT was performed for 12 patients with cervical cancer. Brachytherapy simulation was performed after an external-beam radiation therapy median dose of 4140 cGy. Patients underwent FDG-PET/CT scans with placement of tandem and ovoid applicators. The gross tumor volume (GTV) was determined by adjusting the window and level to a reasonable value and outlining the edge of the enhancing area, which was done in consultation with a nuclear medicine physician. A standardized uptake value profile of the tumor margin was taken for each patient relative to the maximum uptake value of each tumor and analyzed. The plan was designed to deliver 400 cGy to point A (point A plan) or to cover the clinical target volume (CTV) (PET/CT plan). Results: The median dose that encompassed 95% of the target volume (D95) of the CTV was 323.0 cGy for the point A plan vs 399.0 cGy for the PET/CT plan (P=.001). The maximum standardized uptake values (SUVmax) of the tumors were reduced by a median of 57% (range, 13%-80%). All but 1 patient presented with discernable residual uptake within the tumors. The median value of the thresholds of the tumors contoured by simple visual analysis was 41% (range, 23%-71%). Conclusions: In this study, the PET/CT plan was better than the conventional point A plan in terms of target coverage without increasing the dose to the normal tissue, making optimized 3-dimensional brachytherapy treatment planning possible. In comparison with the previously reported study with PET or CT alone, we found that visual target localization was facilitated by PET fusion on indeterminate CT masses. Further studies are needed to characterize the metabolic activity detected during radiation therapy for more reliable targeting. [Copyright &y& Elsevier]