ERK inhibition aids IFN-ß promoter activation during EV71 infection by blocking CRYAB degradation in SH-SY5Y cells.

Enterovirus 71 (EV71) can cause severe hand-foot-and-mouth disease with neurological complications. It has evolved multiple mechanisms to compromise the host type I interferon (IFN-I) response. In neuronal cells, EV71-mediated IFN-I antagonism may be associated with neural precursor cell-expressed developmentally downregulated 4-like (Nedd4L), the E3 ubiquitin ligase that can interact with alphaB-crystallin (CRYAB) in the regulation of Nav1.5 stability. Here, we investigated the effect of CRYAB stability on IFN-ß promoter activity in neuronal SH-SY5Y cells infected with EV71, and its relations to Nedd4 L and extracellular signal-regulated kinases (ERK). Results showed that EV71 infection significantly caused CRYAB degradation via the Nedd4L-proteasome pathway, which required ERK-mediated phosphorylation of Serine 45 in CRYAB. Subsequently, it was observed that siRNA- or EV71-mediated CRYAB reduction limited Poly(dAT)-activated IFN-ß promoter, and CRYAB stabilisation by U0126-mediated inhibition of ERK activation remarkably enhanced the activity of IFN-ß promoter upon EV71 challenge. Collectively, we elucidate a novel mechanism by which ERK activation contributes to EV71 immune escape via CRYAB/IFN-ß axis in SH-SY5Y cells, indicating that perturbing ERK activation is desirable for anti-EV71 therapy.

Synaptic Loss in Spinocerebellar Ataxia Type 3 Revealed by SV2A Positron Emission Tomography.

BACKGROUND: Severe reduced synaptic density was observed in spinocerebellar ataxia (SCA) in postmortem neuropathology, but in vivo assessment of synaptic loss remains challenging. OBJECTIVE SPINOCEREBELLAR ATAXIA TYPE 3: The objective of this study was to assess in vivo synaptic loss and its clinical correlates in spinocerebellar ataxia type 3 (SCA3) patients by synaptic vesicle glycoprotein 2A (SV2A)-positron emission tomography (PET) imaging. METHODS: We recruited 74 SCA3 individuals including preataxic and ataxic stages and divided into two cohorts. All participants received SV2A-PET imaging using 18 F-SynVesT-1 for synaptic density assessment. Specifically, cohort 1 received standard PET procedure and quantified neurofilament light chain (NfL), and cohort 2 received simplified PET procedure for exploratory purpose. Bivariate correlation was performed between synaptic loss and clinical as well as genetic assessments. RESULTS: In cohort 1, significant reductions of synaptic density were observed in cerebellum and brainstem in SCA3 ataxia stage compared to preataxic stage and controls. Vermis was found significantly involved in preataxic stage compared to controls. Receiver operating characteristic (ROC) curves highlighted SV2A of vermis, pons, and medulla differentiating preataxic stage from ataxic stage, and SV2A combined with NfL improved the performance. Synaptic density was significantly negatively correlated with disease severity in cerebellum and brainstem (International Co-operative Ataxia Rating Scale: ρ ranging from -0.467 to -0.667, P ≤ 0.002; Scale of Assessment and Rating of Ataxia: ρ ranging from -0.465 to -0.586, P ≤ 0.002). SV2A reduction tendency of cerebellum and brainstem identified in cohort 1 was observed in cohort 2 with simplified PET procedure. CONCLUSIONS: We first identified in vivo synaptic loss was related to disease severity of SCA3, suggesting SV2A PET could be a promising clinical biomarker for disease progression of SCA3. © 2023 International Parkinson and Movement Disorder Society.

The Potential Prognostic Value of Dual-Imaging PET Parameters Based on 18F-FDG and 18F-OC for Neuroendocrine Neoplasms.

Background: To identify parameters based on dual-imaging 18F-AlF-NOTA-octreotide (18F-OC) and 18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) for predicting the prognosis of neuroendocrine neoplasms (NENs). Materials and Methods: Sixty-six patients (age: mean ± standard deviation (SD): 51.8 ± 11.8 years) who underwent both 18F-OC and 18F-FDG PET/CT imaging were enrolled in our retrospective study. The following PET parameters were measured: the maximum standardized uptake value (SUVmax) and the volumetric parameters-18F-OC SSR-derived tumor volume (TV) and somatostatin receptor expression (SRE, TV multiplied by the mean standardized uptake value (SUVmean)) and the 18F-FDG-derived multiple tumor volume (MTV) and tumor lesion glycolysis (TLG). The NETPET grade based on dual-imaging PET images was assessed. Progression-free survival (PFS) was set as an endpoint. Univariate and multivariate survival analyses were performed for PET parameters and clinical tumor data. Results: In the univariate survival analyses of clinical information, PFS was significantly associated with age (>45.5 vs ≤45.5, years, P < 0.034) and the presence of bone metastases (P = 0.04). Higher values for the 18F-FDG and 18F-OC volumetric parameters and the NETPET grade were adverse factors for PFS according to the dual-imaging PET parameters. In the multivariate survival analysis, the NETPET grade and SRE were predictors of PFS in NEN patients. Conclusion: The NETPET grade is a potential noninvasive prognostic biomarker for NENs.

Cortical abnormalities of synaptic vesicle protein 2A in focal cortical dysplasia type II identified in vivo with 18F-SynVesT-1 positron emission tomography imaging.

PURPOSE: The loss of synaptic vesicle glycoprotein 2A (SV2A) is well established as the major correlate of epileptogenesis in focal cortical dysplasia type II (FCD II), but this has not been directly tested in vivo. In this positron emission tomography (PET) study with the new tracer 18F-SynVesT-1, we evaluated SV2A abnormalities in patients with FCD II and compared the pattern to 18F-fluorodeoxyglucose (18F-FDG). METHODS: Sixteen patients with proven FCD II and 16 healthy controls were recruited. All FCD II patients underwent magnetic resonance imaging (MRI) and static PET imaging with both 18F-SynVesT-1 and 18F-FDG, while the controls underwent MRI and PET with only 18F-SynVesT-1. Visual assessment of PET images was undertaken. The standardized uptake values (SUVs) of 18F-SynVesT-1 were computed for regions of interest (ROIs), along with SUV ratio (SUVr) between ROI and centrum semiovale (white matter). Asymmetry indices (AIs) were analyzed between the lesion and the contralateral hemisphere for intersubject comparisons. RESULTS: Lesions in the brains of FCD II patients had significantly reduced 18F-SynVesT-1 uptake compared with contralateral regions, and brains of the controls. 18F-SynVesT-1 PET indicated low lesion uptake in 14 patients (87.5%), corresponding to hypometabolism detected by 18F-FDG PET, with higher accuracy for lesion localization than MRI (43.8%) (P < 0.05). AI analyses demonstrated that in the lesions, SUVr for each of the radiotracers were not significantly different (P > 0.05), and 18F-SynVesT-1 SUVr correlated with that of 18F-FDG across subjects (R2 = 0.41, P = 0.008). Subsequent visual ratings indicated that 18F-SynVesT-1 uptake had a more restricted pattern of reduction than 18F-FDG uptake in FCD II lesions (P < 0.05). CONCLUSION: SV2A PET with 18F-SynVesT-1 shows a higher accuracy for the localization of FCD II lesions than MRI and a more restricted pattern of abnormality than 18F-FDG PET.

Prognostic Value of Volume-Based Parameters Measured by SSTR PET/CT in Neuroendocrine Tumors: A Systematic Review and Meta-Analysis.

Purpose: A meta-analysis was conducted to investigate the value of the volume parameters based on somatostatin receptor (SSTR)-positron emission tomography (PET) in predicting the prognosis in patients with neuroendocrine tumors (NETs). Material: PUBMED, EMBASE, Cochrane library, and Web of Knowledge were searched from January 1990 to May 2021 for studies evaluating prognostic value of volume-based parameters of SSTR PET/CT in NETs. The terms used were "volume," "positron emission tomography," "neuroendocrine tumors," and "somatostatin receptor." Pooled hazard ratio (HR) values were calculated to assess the correlations between volumetric parameters, including total tumor volume (TTV) and total-lesion SSTR expression (TL-SSTR), with progression-free survival (PFS) and overall survival (OS). Heterogeneity and subgroup analysis were performed. Funnel plots, Begg's and Egger's test were used to assess possible underlying publication bias. Results: Eight eligible studies involving 593 patients were included in the meta-analysis. In TTV, the pooled HRs of its prognostic value of PFS and OS were 2.24 (95% CI: 1.73-2.89; P < 0.00001) and 3.54 (95% CI, 1.77-7.09; P = 0.0004), respectively. In TL-SSTR, the pooled HR of the predictive value was 1.61 (95% CI, 0.48-5.44, P = 0.44) for PFS. Conclusion: High TTV was associated with a worse prognosis for PFS and OS in with patients NETs. The TTV of SSTR PET is a potential objective prognosis predictor.

Biodistribution of 18F-AlF-NOTA-octreotide in Different Organs and Characterization of Uptake in Neuroendocrine Neoplasms.

PURPOSE: The aims of this study were threefold: [1] to describe the biodistribution of 18F-AlF-NOTA-octreotide (18F-OC) in normal organs; [2] to evaluate the range of uptake of NEN and benign lesions using the maximum standardized uptake value (SUVmax); and [3] to compare the difference in 18F-OC uptake among tumors of different grades. METHODS: This study included 162 patients (67 females and 95 males) who received 18F-OC positron emission tomography (PET)/computed tomography (CT), 128 of whom were diagnosed with neuroendocrine neoplasms (NENs). The SUVmax and SUVmean of 18F-OC were measured in 21 normal anatomical structures. We compared the differences among G1, G2, and G3 NENs, as well as between NENs and benign lesions. RESULTS: High physiological uptake of 18F-OC (SUVmax > 6.77) was detected in the spleen, adrenal gland, renal parenchyma, pituitary gland, and liver. Moderate uptake (SUVmax 3.00-6.77) was found in the uncinate process of the pancreas (PU), prostate, thyroid, and uterus. Mild uptake (SUVmax 1.34-3.00) was observed in the small intestine, pancreas (pancreas uptake except for the head of the pancreas), gallbladder, and transverse colon. The SUVmax of NENs was higher than that of benign lesions, including fractures, inflamed tissue, reactive hyperplasia, and degenerative disease. However, overlap was noted between the two groups. The SUVmax of 18F-OC uptake by tumors was significantly correlated with tumor grade in primary lesions and those of the lymph node, bone, and other sites (all P < 0.01). CONCLUSIONS: The results obtained from the majority of the samples in this study show the biodistribution of 18F-OC in normal organs and have significance as a reference. Although some benign lesions show variable uptake, the uptake by these lesions is still different from that of NENs. NENs of different grades have differences in 18F-OC uptake levels.

Evaluation of 18F-AlF-NOTA-octreotide for imaging neuroendocrine neoplasms: comparison with 68Ga-DOTATATE PET/CT.

OBJECTIVE: To evaluate the diagnostic efficacy of 18F-AlF-NOTA-octreotide (18F-OC) PET/CT compared with that of 68Ga-DOTATATE PET/CT. MATERIALS AND METHODS: Twenty patients (mean age: 52.65 years, range: 24-70 years) with biopsy-proven neuroendocrine neoplasms (NENs) were enrolled in this prospective study. We compared the biodistribution profiles in normal organs based on the maximum standard uptake value (SUVmax) and mean standard uptake value (SUVmean), and uptake in NEN lesions by measuring the SUVmax on 18F-OC and 68Ga-DOTATATE PET/CT images. The tumor-to-liver ratio (TLR) and tumor-to-spleen ratio were calculated by dividing the SUVmax of different tumor lesions by the SUVmean of the liver and spleen, respectively. The Wilcoxon signed-rank test was used to compare nonparametric data. Data were expressed as the median (interquartile range). RESULTS: In most organs, there were no significant differences in the biodistribution of 68Ga-DOTATATE and 18F-OC. 18F-OC had significantly lower uptake in the salivary glands and liver than 68Ga-DOTATATE. 18F-OC detected more lesions than 68Ga-DOTATATE. The uptake of 18F-OC in the tumors was higher in most patients, but the difference was not statistically significant relative to that of 68Ga-DOTATATE. However, the TLRs of 18F-OC were higher in most patients, including for lesions in the liver (p = 0.02) and lymph nodes (p = 0.02). CONCLUSION: Relative to 68Ga-DOTATATE, 18F-OC possesses favorable characteristics with similar image quality and satisfactory NEN lesion detection rates, especially in the liver due to its low background uptake. 18F-OC therefore offers a promising clinical alternative for 68Ga-DOTATATE.

Utility of 18F-AlF-NOTA-Octreotide PET/CT in the Localization of Tumor-Induced Osteomalacia.

CONTEXT: Tumor-induced osteomalacia (TIO) is a paraneoplastic disorder, usually caused by benign mesenchymal tumors that produce high levels of fibroblast growth factor 23. The only curative therapy is resection of the causative tumors. OBJECTIVE: This research was conducted to evaluate the efficacy of 18F-AlF-NOTA-octreotide (18F-OC) positron emission tomography/computed tomography (PET/CT) in detecting TIO and its impact on patient management. METHODS: Retrospective analysis was conducted of 17 patients with hypophosphatemic osteomalacia suspected to be TIO. A  18F-OC PET/CT study was performed in all 17 patients to localize the tumor and 68Ga-DOTATATE PET/CT was performed in 4 out of 17 patients; both studies were performed within 1 week of each other. Both studies were interpreted blindly without the knowledge of other imaging findings. The image findings were compared with the results of histopathological examinations and clinical follow-ups. RESULTS: The 18F-OC PET/CT scans were positive in 14 patients. Furthermore, 4 of 14 patients were scanned with both 18F-OC and 68Ga-DOTATATE PET/CT. Both studies were able to localize the tumor in all 4 patients. In total, 14 patients had surgery to remove the lesions. Postsurgical pathological examination confirmed causative tumors in these patients, whose symptoms diminished promptly. Serum phosphate levels normalized, confirming the diagnosis of TIO. 18F-OC PET/CT sensitivity, specificity, and accuracy were 87.5%, 100%, and 88.2% respectively. 18F-OC PET/CT findings affected patient management in 88.2% of cases. CONCLUSION: 18F-OC PET/CT scan is useful in the detection of tumors causing TIO. Further studies with larger patient populations are needed to validate the result.

18 F-2-fluoro-2-deoxy-D-glucose-positron emission tomography metabolic pattern assessment in the brain of betel quid dependent individuals.

The primary objective of this study was to identify the metabolic pattern in the brains of betel quid dependent (BQD) individuals using 18 F-2-fluoro-2-deoxy-D-glucose-positron emission tomography (18 F-FDG-PET). A total of 42 individuals (16 BQD individuals and 26 healthy controls, HCs) enrolled at the Department of Nuclear Medicine of Xiangya Hospital underwent brain 18 F-FDG-PET. Group comparisons using statistical parametric mapping (SPM) were performed to identify the 18 F-FDG-PET patterns. Standardized uptake value ratios of anterior cingulate, frontal, thalamus, parietal, occipital, temporal and cerebellum were calculated by SPM. The characteristics of abnormal metabolism in brain regions were quantified using the xjView toolbox, and a 3-D brain map was drawn using BrainNet Viewer. We found significant metabolic reduction in the bilateral middle prefrontal cortex (PFC) and the left orbital frontal gyrus (OFC). In contrast, hypermetabolism was observed in the inferior cerebellum, fusiform, superior cerebellum, parahippocampal, vermis, lingual and thalamus. However, we found no significant difference between the BQD and HC group in the anterior cingulate, thalamus, cerebellum and frontal, temporal, parietal and occipital lobes. In summary, we found abnormal 18 F-FDG-PET metabolic pattern in BQD individuals, and this pattern may help the treatment of BQD.

Individual Brain Metabolic Connectome Indicator Based on Jensen-Shannon Divergence Similarity Estimation Predicts Seizure Outcomes of Temporal Lobe Epilepsy.

Objective: We aimed to use an individual metabolic connectome method, the Jensen-Shannon Divergence Similarity Estimation (JSSE), to characterize the aberrant connectivity patterns and topological alterations of the individual-level brain metabolic connectome and predict the long-term surgical outcomes in temporal lobe epilepsy (TLE). Methods: A total of 128 patients with TLE (63 females, 65 males; 25.07 ± 12.01 years) who underwent Positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) imaging were enrolled. Patients were classified either as experiencing seizure recurrence (SZR) or seizure free (SZF) at least 1 year after surgery. Each individual's metabolic brain network was ascertained using the proposed JSSE method. We compared the similarity and difference in the JSSE network and its topological measurements between the two groups. The two groups were then classified by combining the information from connection and topological metrics, which was conducted by the multiple kernel support vector machine. The validation was performed using the nested leave-one-out cross-validation strategy to confirm the performance of the methods. Results: With a median follow-up of 33 months, 50% of patients achieved SZF. No relevant differences in clinical features were found between the two groups except age at onset. The proposed JSSE method showed marked degree reductions in IFGoperc.R, ROL. R, IPL. R, and SMG. R; and betweenness reductions in ORBsup.R and IOG. R; meanwhile, it found increases in the degree analysis of CAL. L and PCL. L, and in the betweenness analysis of PreCG.R, IOG. R, PoCG.R, PCL. L and PCL.R. Exploring consensus significant metabolic connections, we observed that the most involved metabolic motor networks were the INS-TPOmid.L, MTG. R-SMG. R, and MTG. R-IPL.R pathways between the two groups, and yielded another detailed individual pathological connectivity in the PHG. R-CAU.L, PHG. R-HIP.L, TPOmid.L-LING.R, TPOmid.L-DCG.R, MOG. R-MTG.R, MOG. R-ANG.R, and IPL. R-IFGoperc.L pathways. These aberrant functional network measures exhibited ideal classification performance in predicting SZF individuals from SZR ones at a sensitivity of 75.00%, a specificity of 92.79%, and an accuracy of 83.59%. Conclusion: The JSSE method indicator can identify abnormal brain networks in predicting an individual's long-term surgical outcome of TLE, thus potentially constituting a clinically applicable imaging biomarker. The results highlight the biological meaning of the estimated individual brain metabolic connectome.

Machine Learning-Derived Multimodal Neuroimaging of Presurgical Target Area to Predict Individual's Seizure Outcomes After Epilepsy Surgery.

Objectives: Half of the patients who have tailored resection of the suspected epileptogenic zone for drug-resistant epilepsy have recurrent postoperative seizures. Although neuroimaging has become an indispensable part of delineating the epileptogenic zone, no validated method uses neuroimaging of presurgical target area to predict an individual's post-surgery seizure outcome. We aimed to develop and validate a machine learning-powered approach incorporating multimodal neuroimaging of a presurgical target area to predict an individual's post-surgery seizure outcome in patients with drug-resistant focal epilepsy. Materials and Methods: One hundred and forty-one patients with drug-resistant focal epilepsy were classified either as having seizure-free (Engel class I) or seizure-recurrence (Engel class II through IV) at least 1 year after surgery. The presurgical magnetic resonance imaging, positron emission tomography, computed tomography, and postsurgical magnetic resonance imaging were co-registered for surgical target volume of interest (VOI) segmentation; all VOIs were decomposed into nine fixed views, then were inputted into the deep residual network (DRN) that was pretrained on Tiny-ImageNet dataset to extract and transfer deep features. A multi-kernel support vector machine (MKSVM) was used to integrate multiple views of feature sets and to predict seizure outcomes of the targeted VOIs. Leave-one-out validation was applied to develop a model for verifying the prediction. In the end, performance using this approach was assessed by calculating accuracy, sensitivity, and specificity. Receiver operating characteristic curves were generated, and the optimal area under the receiver operating characteristic curve (AUC) was calculated as a metric for classifying outcomes. Results: Application of DRN-MKSVM model based on presurgical target area neuroimaging demonstrated good performance in predicting seizure outcomes. The AUC ranged from 0.799 to 0.952. Importantly, the classification performance DRN-MKSVM model using data from multiple neuroimaging showed an accuracy of 91.5%, a sensitivity of 96.2%, a specificity of 85.5%, and AUCs of 0.95, which were significantly better than any other single-modal neuroimaging (all p ˂ 0.05). Conclusion: DRN-MKSVM, using multimodal compared with unimodal neuroimaging from the surgical target area, accurately predicted postsurgical outcomes. The preoperative individualized prediction of seizure outcomes in patients who have been judged eligible for epilepsy surgery could be conveniently facilitated. This may aid epileptologists in presurgical evaluation by providing a tool to explore various surgical options, offering complementary information to existing clinical techniques.

Residual Stress and Microstructure Characterization of 34CrMo4 Steel Modified by Shot Peening.

34CrMo4 steel is widely used for drill stem in oil exploration, because of its excellent properties, such as favorable hardenability, shock absorption, less tendency of temper brittleness, and eminent wear resistance. In this study, the main works are residual stress test and microstructure characterization of 34CrMo4 steel upon various shot peening treatments. The residual stress distribution with effect depth was studied upon the shot peening. Face-to-face paste sample preparation method is required for continuous observation for microstructure evolution of shot-peened specimen from the treat surface to matrix. Grain refinement, lath structure, and precipitates are clearly observed in the gradient deformation layer.

FDG-PET Profiles of Extratemporal Metabolism as a Predictor of Surgical Failure in Temporal Lobe Epilepsy.

Objective: Metabolic abnormality in the extratemporal area on fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) is not an uncommon finding in drug-resistant temporal lobe epilepsy (TLE), however the correlation between extratemporal metabolic abnormalities and surgical long-term prognosis has not been fully elucidated. We aim to investigate FDG-PET extratemporal metabolic profiles predictive of failure in surgery for TLE patients. Methods: Eighty-two patients with unilateral TLE (48 female, 34 male; 25.6 ± 10.6 years old; 37 left TLE, 45 right TLE) and 30 healthy age-matched controls were enrolled. Patients were classified either as experiencing seizure-recurrence (SZR, Engel class II through IV) or seizure-free (SZF, Engel class I) at least 1 year after surgery. Regional cerebral metabolism was evaluated by FDG-PET with statistical parametric mapping (SPM12). Abnormal metabolic profiles and patterns on FDG-PET in SZR group were evaluated and compared with those of healthy control and SZF subjects on SPM12. Volume and intensity as well as special brain areas of abnormal metabolism in temporal and extratemporal regions were quantified and visualized. Results: With a median follow-up of 1.5 years, 60% of patients achieved Engel class I (SZF). SZR was associated with left TLE and widespread hypometabolism in FDG-PET visual assessment (both p < 0.05). All patients had hypometabolism in the ipsilateral temporal lobe but SZR was not correlated with volume or intensity of temporal hypometabolism (median, 1,456 vs. 1,040 mm3; p > 0.05). SZR was correlated with extratemporal metabolic abnormalities that differed according to lateralization: in right TLE, SZR exhibited larger volume in extratemporal areas compared to SZF (median, 11,060 vs. 2,112 mm3; p < 0.05). Surgical failure was characterized by Cingulum_Ant_R/L, Frontal_Inf_Orb_R abnormal metabolism in extratemporal regions. In left TLE, SZR presented a larger involvement of extratemporal areas similar to right TLE but with no significant (median, 5,873 vs. 3,464 mm3; p > 0.05), Cingulum_Ant_ R/L, Parietal_Inf_L, Postcentral_L, and Precuneus_R involved metabolic abnormalities were correlated with SZR. Conclusions: Extratemporal metabolic profiles detected by FDG-PET may indicate a prominent cause of TLE surgery failure and should be considered in predictive models for epilepsy surgery. Seizure control after surgery might be improved by investigating extratemporal areas as candidates for resection or neuromodulation.

Clinical Application of 18F-AlF-NOTA-Octreotide PET/CT in Combination With 18F-FDG PET/CT for Imaging Neuroendocrine Neoplasms.

OBJECTIVES: The study is to evaluate biodistribution, dosimetry, safety, and clinical usefulness of F-AlF-NOTA-octreotide (F-OC) PET/CT in combination with F-FDG PET/CT for detection of neuroendocrine neoplasms (NENs). METHODS: The biodistribution, dosimetry, and safety of F-OC were evaluated in 3 healthy volunteers. Twenty-two NEN patients underwent PET/CT at 60 minutes after intravenous injection of 3.7 to 4.44 MBq (0.1-0.12 mCi) per kilogram of body weight of F-OC. This was followed by F-FDG PET/CT within a 2-week period. RESULTS: F-OC was well tolerated by all healthy volunteers and NEN patients. The calculated effective dose of F-OC was 0.023 ± 0.002 mSv/MBq. In NEN patients, we observed prominent F-OC tumor uptake and high tumor-to-background ratios. Tumor uptake of F-OC was greater than that of F-FDG, and this was particularly evident in G2 NENs (median SUVmax, 45.6 vs 4.3; P < 0.015). Tumor uptake of F-OC or F-FDG was significantly correlated with tumor differentiation (P < 0.05). Dual tracer PET/CT detected more lesions and also yielded information on the biological status of tumors. CONCLUSIONS: The tracer F-OC exhibited favorable safety and dosimetry profiles. F-OC provided superior imaging of well-differentiated NENs and significantly higher tumor-to-background ratio compared with F-FDG. Combining F-FDG with F-OC PET/CT has the potential to improve NEN staging and management of patient treatment.

Effect of Plastic Deformation on Microstructure and Properties of 347 Austenite Steel.

A popular issue of recent scientific research is the surface modification induced by plastic deformation, such as ultrasonic shot peening (USP) on workpiece surface. USP is an efficient way to improve the mechanical behavior of specimens by inducing severe plastic deformation on their surface. Nevertheless, this surface treatment induced complex microstructural evolutions, such as grain refinement and phase transformation. In this work, the microstructure and properties of 347 austenite steel samples before and after USP for 5, 10, and 15 min treatments have been investigated. The affected layers show a significant hardness increase (~450 µm in depth) on the USP treated surface, and the 10 min USP treated specimen shows the best corrosion resistance in all tested specimens. The magnetic properties and microstructures of the tested specimens show gradient evolution during deformation.

Impact of paranasal sinus invasion on advanced nasopharyngeal carcinoma treated with intensity-modulated radiation therapy: the validity of advanced T stage of AJCC/UICC eighth edition staging system.

The aim of this study was to clarify the prognostic role of paranasal sinus invasion in advanced NPC patients. Data of patients (n = 295) with advanced NPC (T3/T4N0-3 M0) treated with intensity-modulated radiation therapy were retrospectively analyzed. Staging was according to the AJCC/UICC eighth edition staging system. Overall survival (OS), local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS) were calculated, and differences were compared between patients with and without paranasal sinus invasion. Multivariate analysis was used to identify the independent predictors of different survival parameters. Paranasal sinus invasion was present in 126 of 295 (42.7%) patients. Sphenoid, ethmoid, maxillary, and frontal sinus involvements were present in 123 of 295 (41.7%), 95 of 295 (32.2%), 45 of 295 (15.3%), and 0 of 295 (0%), respectively. All survival parameters were significantly better in patients without paranasal sinus invasion. When paranasal sinus invasion was reclassified as T4 instead of T3, all survival rates, other than LRFS (P = 0.156), were significantly better in the new T3 patients, and differences in all survival parameters remained nonsignificant between T3 with paranasal sinus invasion and T4 without paranasal sinus invasion patients (all P > 0.05). In multivariate analysis, paranasal sinus invasion was found to be an independent negative prognostic factor for OS, DFS, and DMFS (P = 0.016, P = 0.004, and P = 0.006, respectively), but not for LRFS (P = 0.068). Paranasal sinus invasion has prognostic value in advanced NPC. It may be reasonable to classify paranasal sinus invasion as T4 stage.

Effect of heat treatment on the microstructure and properties of Ni based soft magnetic alloy.

A Ni-based alloy was heat treated by changing the temperature and ambient atmosphere of the heat treatment. Morphology, crystal structure, and physical performance of the Ni-based alloy were characterized via SEM, XRD, TEM, and PPMS. Results show that due to the heat treatment process, the grain growth of the Ni-based alloy and the removal of impurities and defects are promoted. Both the orientation and stress caused by rolling are reduced. The permeability and saturation magnetization of the alloy are improved. The hysteresis loss and coercivity are decreased. Higher heat treatment temperature leads to increased improvement of permeability and saturation magnetization. Heat treatment in hydrogen is more conducive to the removal of impurities. At the same temperature, the magnetic performance of the heat-treated alloy in hydrogen is better than that of an alloy with heat treatment in vacuum. The Ni-based alloy shows an excellent magnetic performance on 1,373 K heat treatment in hydrogen atmosphere. In this process, the µm , Bs , Pu , and Hc of the obtained alloy are 427 mHm-1 , 509 mT, 0.866 Jm-3 , and 0.514 Am-1 , respectively. At the same time, the resistivity of alloy decreases and its thermal conductivity increases in response to heat treatment.

Injectable and thermally contractible hydroxypropyl methyl cellulose/Fe3O4 for magnetic hyperthermia ablation of tumors.

The development of efficient strategies for the magnetic hyperthermia ablation of tumors remains challenging. To overcome the significant safety limitations, we developed a thermally contractible, injectable and biodegradable material for the minimally invasive and highly efficient magnetic hyperthermia ablation of tumors. This material was composed of hydroxypropyl methyl cellulose (HPMC), polyvinyl alcohol (PVA) and Fe3O4. The thermal contractibility of HPMC/Fe3O4 was designed to avoid damaging the surrounding normal tissue upon heating, which was confirmed by visual inspection, ultrasound imaging and computed tomography (CT). The efficient injectability of HPMC/Fe3O4 was proven using a very small needle. The biosafety of HPMC/Fe3O4 was evaluated by MTT and biochemical assays as well as flow cytometry (FCM). All the aforementioned data demonstrated the safety of HPMC/Fe3O4. The results of in vitro and ex vivo experiments showed that the temperature and necrotic volume of excised bovine liver were positively correlated with the HPMC/Fe3O4 weight, iron content and heating duration. The in vivo experimental results showed that the tumors could be completely ablated using 0.06 ml of HPMC/60%Fe3O4 after 180 s of induction heating. We believe that this novel, safe and biodegradable material will promote the rapid bench-to-bed translation of magnetic hyperthermia technology, and it is also expected to bring a new concept for the biomaterial research field.

Characterization of Surface Modification of 347 Stainless Steel upon Shot Peening.

Plastic deformations, such as those obtained by shot peening on specimen surface, are an efficient way to improve the mechanical behavior of metals. Generally, scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD) are commonly used to observe the complex microstructural evolutions, such as grain refinement and phase transformation, induced by the surface treatment. In this work, the microstructure of 347 stainless steel, after ultrasonic shot peening (USP) treatments, was investigated. SEM, EBSD, transmission electron microscopy, and X-ray diffraction were used to observe the microstructural evolutions, such as grain refinement and phase transformation. Deformation depth after the USP treatment was about 200 µm. Grain size on the treated surface layer was about 100 nm, with two phases: austenite and α'-martensite. The percentages of the austenite and α'-martensite phases were 54% and 46%, respectively, which constitute an exact expression of the degree of plastic deformation on austenitic stainless steel.

Corrosion Properties of 34CrMo4 Steel Modified by Shot Peening.

A nanocrystalline layer was prepared on the surface of 34CrMo4 steel by time controlling shot peening (SP, i.e., 1, 5, 10, and 20 minutes). Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) analysis, and transmission electron microscope (TEM) were applied to analyze the surface, cross-sections, and grain size of the specimens before and after SP. The electrochemical corrosion behavior was used to simulate a liquid under the oil and gas wells environment. It was characterized by the potentiodynamic polarization test and electrochemical impedance spectroscopy (EIS). The analysis results show that the surfaces of the SP samples were very rough and had numerous cracks. A passive film on SP surface was formed by nanocrystalline grains. However, the passive film formed in the initial stage was not dense or uniform, and cracks occurred in the passive film during peening, resulting in a decrease in corrosion resistance.