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Introduction: To explore and evaluate the performance of MRI‐based brain tumor super‐resolution generative adversarial network (MRBT‐SR‐GAN) for improving the MRI image resolution in brain tumors. Methods: A total of 237 patients from December 2018 and April 2020 with T2‐fluid attenuated inversion recovery (FLAIR) MR images (one image per patient) were included in the present research to form the super‐resolution MR dataset. The MRBT‐SR‐GAN was modified from the enhanced super‐resolution generative adversarial networks (ESRGAN) architecture, which could effectively recover high‐resolution MRI images while retaining the quality of the images. The T2‐FLAIR images from the brain tumor segmentation (BRATS) dataset were used to evaluate the performance of MRBT‐SR‐GAN contributed to the BRATS task. Results: The super‐resolution T2‐FLAIR images yielded a 0.062 dice ratio improvement from 0.724 to 0.786 compared with the original low‐resolution T2‐FLAIR images, indicating the robustness of MRBT‐SR‐GAN in providing more substantial supervision for intensity consistency and texture recovery of the MRI images. The MRBT‐SR‐GAN was also modified and generalized to perform slice interpolation and other tasks. Conclusions: MRBT‐SR‐GAN exhibited great potential in the early detection and accurate evaluation of the recurrence and prognosis of brain tumors, which could be employed in brain tumor surgery planning and navigation. In addition, this technique renders precise radiotherapy possible. The design paradigm of the MRBT‐SR‐GAN neural network may be applied for medical image super‐resolution in other diseases with different modalities as well. [ABSTRACT FROM AUTHOR]

In order to effectively extend the lifetime of Internet of Things (IoT) devices, improve the energy efficiency of task processing, and build a self-sustaining and green edge computing system, this paper proposes an efficient and energy-saving computation offloading mechanism with energy harvesting for IoT. Specifically, based on the comprehensive consideration of local computing resource, time allocation ratio of energy harvesting, and offloading decision, an optimization problem that minimizes the total energy consumption of all user devices is formulated. In order to solve such optimization problem, a deep learning-based efficient and energy-saving offloading decision and resource allocation algorithm is proposed. The design of deep neural network architecture incorporating regularization method and the employment of the stochastic gradient descent method can accelerate the convergence rate of the developed algorithm and improve its generalization performance. Furthermore, it can minimize the total energy consumption of task processing by integrating the momentum gradient descent to solve the resource optimization allocation problem. Finally, the simulation results show that the mechanism proposed in this paper has significant advantage in convergence rate and can achieve an optimal offloading and resource allocation strategy that is close to the solution of greedy algorithm. [ABSTRACT FROM AUTHOR]

Background: Isocitrate dehydrogenase wild-type (WT) glioblastoma (GBM) accounts for 90% of all GBMs, yet only 27% of isocitrate dehydrogenase WT-GBMs have p53 mutations. However, the tumor surveillance function of WT-p53 in GBM is subverted by mechanisms that are not fully understood.Methods: We investigated the proteolytic inactivation of WT-p53 by asparaginyl endopeptidase (AEP) and its effects on GBM progression in cancer cells, murine models, and patients' specimens using biochemical and functional assays. The sera of healthy donors (n = 48) and GBM patients (n = 20) were examined by enzyme-linked immunosorbent assay. Furthermore, effects of AEP inhibitors on GBM progression were evaluated in murine models (n = 6-8 per group). The statistical significance between groups was determined using two-tailed Student t tests.Results: We demonstrate that AEP binds to and directly cleaves WT-p53, resulting in the inhibition of WT-p53-mediated tumor suppressor function in both tumor cells and stromal cells via extracellular vesicle communication. High expression of uncleavable p53-N311A-mutant rescue AEP-induced tumorigenesis, proliferation, and anti-apoptotic abilities. Knock down or pharmacological inhibition of AEP reduced tumorigenesis and prolonged survival in murine models. However, overexpression of AEP promoted tumorigenesis and shortened the survival time. Moreover, high AEP levels in GBM tissues were associated with a poor prognosis of GBM patients (n = 83; hazard ratio = 3.94, 95% confidence interval = 1.87 to 8.28; P < .001). A correlation was found between high plasma AEP levels and a larger tumor size in GBM patients (r = 0.6, P = .03), which decreased dramatically after surgery.Conclusions: Our results indicate that AEP promotes GBM progression via inactivation of WT-p53 and may serve as a prognostic and therapeutic target for GBM. [ABSTRACT FROM AUTHOR]

The current study used a rat middle cerebral artery occlusion (MCAO) model with the aim to explore the effects of compound porcine cerebroside and ganglioside injection (CPCGI) on brain ischemia/reperfusion injury in rats. Improvement in the infarct-side microcirculation and the overall recovery of neurological function were detected by triphenyltetrazolium chloride staining, laser speckle blood flow monitoring, latex perfusion, immunofluorescence and immunoblotting. The results revealed that administration of CPCGI for 7 consecutive days following ischemic stroke contributed to the recovery of neurological function and the reduction of cerebral infarct volume in rats. Blood flow monitoring results demonstrated that the administration of CPCGI effectively promoted cerebral blood flow following stroke, and contributed to the protection of the ischemic side blood vessels. In addition, CPCGI treatment increased the numbers of new blood vessels in the peripheral ischemic region, and upregulated the expression levels of vascular endothelial growth factor, angiopoietin 1 and its receptor TEK receptor tyrosine kinase, fibroblast growth factor and Wnt signaling pathway-associated proteins. Taken together, the present results indicated that CPCGI improved the blood circulation and neurological function following cerebral ischemia/reperfusion in rats. [ABSTRACT FROM AUTHOR]

Abstract: Human non-functioning pituitary adenomas cause hypopituitarism or the compression of adjacent structures. At present, there is no available medical treatment for these tumours. The Notch3 pathway has an important role in the progression of non-functioning pituitary adenomas. We found, using reverse transcriptase–polymerase chain reaction, that Notch3 mRNA was significantly upregulated in clinically non-functioning pituitary adenomas, and, using Western blotting, that Notch3 protein was expressed at a higher level in non-functioning pituitary adenomas than in normal human pituitary tissue. In addition, using immunohistochemistry, we observed that Notch3 is highly expressed in the cytoplasm of adenoma cells compared to normal pituitary cells. These results suggest that the overexpression of Notch3 mRNA and protein by non-functioning pituitary adenomas may facilitate the growth of these tumours. Our results provide the first comprehensive analysis of Notch3 mRNA and protein overexpression in non-functioning pituitary tumours. This study provides new insights into the pathogenesis of human non-functioning pituitary adenomas and implicates the Notch3 pathway as a molecular therapeutic target for their treatment. [Copyright &y& Elsevier]

Abstract: Brain ischemic postconditioning is the induction of brief periods of ischemia–reperfusion during the early stages following ischemia, and it has been shown to produce neuroprotective effects. The mechanisms underlying these neuroprotective effects are poorly understood. Glutamate excitotoxicity is one cause of postischemic neuronal death. Glutamine synthetase (GS) is an enzyme that is expressed in glial cells and may affect glutamate excitotoxicity. We induced global ischemia in rats and performed postconditioning with 6 cycles of 10seconds reperfusion and 10seconds reocclusion before final reperfusion. Hematoxylin and eosin staining revealed extensive neuronal loss (44.0±2.8% cell survival) in the hippocampal CA1 region. Ischemic postconditioning decreased neuronal death (82.0±5.6% cell survival; p <0.05). Western blotting revealed significantly increased GS expression in the hippocampus for the ischemia–reperfusion group over time compared with the sham group (p <0.05). Ischemic postconditioning resulted in significantly increased (p <0.05) GS expression compared with both the sham and ischemia–reperfusion groups, suggesting that upregulation of GS expression after ischemia constitutes a neuroprotective mechanism. [Copyright &y& Elsevier]

Abstract: The objective of this study was to examine the prognostic significance of health-related quality of life (HQOL) parameters combined with baseline clinical factors in patients undergoing neurosurgery for treatment of meningioma. A total of 147 patients (61 male, 86 female; mean age 43years, range 5–77years) who underwent resection of a meningioma between January 2002 and December 2004 were studied. HQOL was evaluated using a modified questionnaire based on the World Health Organization Quality of Life-100 Scale and the Karnofsky Performance Scale. The relationships between HQOL and clinical history, radiological findings, extent of resection, histological grade and recurrence were investigated using multivariate analysis. The mean HQOL score was 73.94±1.79 for preoperative patients with meningioma, 84.88±2.14 for postoperative patients, and 91.13±1.61 for healthy controls. HQOL for patients with meningioma was significantly lower than that for normal controls (P <0.001), and postoperative patients had a more satisfactory HQOL than preoperative (P <0.05). Cox proportional hazards analysis showed that significant predictors of health-related quality of life were tumor size, extent of surgical excision, and histologic grade. Multivariate backward logistic regression yielded the regression equation HQOL=119.1097 – 1.5002X 3 – 8.6650X 6 – 10.4210X 7 (R=0.7466; where X 3 is tumor size, X 6 is extent of surgical excision, and X 7 is the histologic grade of the tumor). This equation can be used preoperatively to predict the HQOL of meningioma patients after neurosurgery. A specialized HQOL questionnaire for patients with meningioma provides useful information when planning the operative procedure, and may make it more likely that patients have a satisfactory HQOL after surgery. [Copyright &y& Elsevier]

LncRNA PVT1 has been implicated in numerous pathophysiological processes and diseases, especially cancers. However, the role and mechanism of PVT1 in the tumorigenesis of glioblastoma remain unclear. We investigated the alteration of PVT1 and its key functions in glioblastoma. PVT1 was upregulated and associated with poor prognosis in glioblastoma. We demonstrated that PVT1 silencing suppressed cell proliferation, colony formation, and orthotopic xenograft tumor growth. Mechanistic investigations found that PVT1 interacted with TRIM24 directly and increased its protein stability. PVT1 recruited COPS5 to deubiquitinate TRIM24; reciprocally, PVT1 depletion impaired the interaction between COPS5 and TRIM24, resulting in decreased expression of TRIM24. PVT1 , TRIM24, and COPS5 coordinately contributed to the activation of STAT3 signaling and malignant phenotype of glioblastoma. Collectively, this study elucidates the essential role of PVT1 in the tumorigenesis of glioblastoma, which provides candidacy therapeutic target for glioblastoma treatment., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)

Background: Isocitrate dehydrogenase wild-type (WT) glioblastoma (GBM) accounts for 90% of all GBMs, yet only 27% of isocitrate dehydrogenase WT-GBMs have p53 mutations. However, the tumor surveillance function of WT-p53 in GBM is subverted by mechanisms that are not fully understood., Methods: We investigated the proteolytic inactivation of WT-p53 by asparaginyl endopeptidase (AEP) and its effects on GBM progression in cancer cells, murine models, and patients' specimens using biochemical and functional assays. The sera of healthy donors (n = 48) and GBM patients (n = 20) were examined by enzyme-linked immunosorbent assay. Furthermore, effects of AEP inhibitors on GBM progression were evaluated in murine models (n = 6-8 per group). The statistical significance between groups was determined using two-tailed Student t tests., Results: We demonstrate that AEP binds to and directly cleaves WT-p53, resulting in the inhibition of WT-p53-mediated tumor suppressor function in both tumor cells and stromal cells via extracellular vesicle communication. High expression of uncleavable p53-N311A-mutant rescue AEP-induced tumorigenesis, proliferation, and anti-apoptotic abilities. Knock down or pharmacological inhibition of AEP reduced tumorigenesis and prolonged survival in murine models. However, overexpression of AEP promoted tumorigenesis and shortened the survival time. Moreover, high AEP levels in GBM tissues were associated with a poor prognosis of GBM patients (n = 83; hazard ratio = 3.94, 95% confidence interval = 1.87 to 8.28; P < .001). A correlation was found between high plasma AEP levels and a larger tumor size in GBM patients (r = 0.6, P = .03), which decreased dramatically after surgery., Conclusions: Our results indicate that AEP promotes GBM progression via inactivation of WT-p53 and may serve as a prognostic and therapeutic target for GBM., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Circular RNAs (circRNAs) are widely expressed non-coding RNAs in eukaryotic cells, involved in regulating tumorigenesis of several types of cancers. However, the expression profiles and the precise functional role in glioblastoma remain unclear., Results: Circ-EPB41L5 was downregulated in glioblastoma tissues and cell lines compared to the normal brain tissues and cell lines. Low circ-EPB41L5 expression was correlated to the poor prognosis of glioblastoma patients, while the overexpression inhibited proliferation, clone formation, migration, and invasion abilities of glioma cells, and the suppression had counter effects. Furthermore, RNA-seq results determined that the host gene was the target gene of circ-EPB41L5, which served as a sponge against miR-19a and inhibited miR-19a activity from upregulating the expression of EPB41L5. Finally, we found that circ-EPB41L5 regulated the RhoC expression and phosphorylation of AKT through EPB41L5., Conclusion: The current study highlights a novel suppressive function of circ-EPB41L5 and reveals that circ-EPB41L5/miR-19a/EPB41L5/p-AKT regulatory axis plays a striking role in the progression of glioblastoma, which provides a novel insight into the mechanisms underlying glioblastoma., Methods: The expression profiles of circRNAs in glioblastoma were determined by Illumina HiSeq from six glioblastoma tissues and six normal brain tissues. Then, the correlation between circ-EPB41L5 expression and clinical features and the survival time of 45 glioblastoma patients was detected. The interaction between circ-EPB41L5, miR-19a, and EPB41L5 was assessed by luciferase reporter and RNA pull-down assays. The effects of expression of the ectopic intervention of circ-EPB41L5 or EPB41L5 on proliferation, clone formation, migration, and invasion in vitro and tumorigenesis in vivo were observed to evaluate the function of circ-EPB41L5 or EPB41L5.

Aim: Human pituitary adenomas account for 10% of intracranial tumours and occur in about 20% of the population. They cause hypopituitarism or the compression of adjacent regional structures. However, little is known about the molecular pathogenesis that contributes to the development of these tumours., Material and Methods: In this study, we investigated the relationship between the expression level of folate receptor alpha and some clinical factors (endocrine, age, gender, repeated operation or not, mean diameter of tumour and invasiveness) of pituitary adenomas. Realtime fluorescent quantitative reverse transcriptase polymerase chain reaction was used to determine the expression of folate receptor alpha mRNA in pituitary adenomas and normal pituitaries. Folate receptor alpha protein levels were quantified using Western blot analysis and Immunohistochemistry., Results: We found folate receptor alpha mRNA and protein were significantly upregulated in clinically nonfunctional pituitary adenomas compared to functional tumours. For nonfunctional tumours, folate receptor alpha expression was much higher in the invasive group than in non-invasive group., Conclusion: These results suggest that the overexpression of folate receptor alpha mRNA and protein by nonfunctional pituitary adenomas may facilitate the growth of these tumours. Potentially, this finding could be exploited to develop innovative molecular targeted diagnosis and treatment for human nonfunctional pituitary adenomas.

Background: The aim of this research was to evaluate the economic outcomes of radiotherapy (RT), temozolomide (TMZ) and nitrosourea (NT) strategies for glioblastoma patients with different prognostic factors., Methodology/principal Findings: A Markov model was developed to track monthly patient transitions. Transition probabilities and utilities were derived primarily from published reports. Costs were estimated from the perspective of the Chinese healthcare system. The survival data with different prognostic factors were simulated using Weibull survival models. Costs over a 5-year period and quality-adjusted life years (QALYs) were estimated. Probabilistic sensitivity and one-way analyses were performed. The baseline analysis in the overall cohort showed that the TMZ strategy increased the cost and QALY relative to the RT strategy by $25,328.4 and 0.29, respectively; and the TMZ strategy increased the cost and QALY relative to the NT strategy by $23,906.5 and 0.25, respectively. Therefore, the incremental cost effectiveness ratio (ICER) per additional QALY of the TMZ strategy, relative to the RT strategy and the NT strategy, amounts to $87,940.6 and $94,968.3, respectively. Subgroups with more favorable prognostic factors achieved more health benefits with improved ICERs. Probabilistic sensitivity analyses confirmed that the TMZ strategy was not cost-effective. In general, the results were most sensitive to the cost of TMZ, which indicates that better outcomes could be achieved by decreasing the cost of TMZ., Conclusions/significance: In health resource-limited settings, TMZ is not a cost-effective option for glioblastoma patients. Selecting patients with more favorable prognostic factors increases the likelihood of cost-effectiveness.

Ischemic postconditioning refers to several transient reperfusion and ischemia cycles after an ischemic event and before a long duration of reperfusion. The procedure produces neuroprotective effects. The mechanisms underlying these neuroprotective effects are poorly understood. In this study, we found that most neurons in the CA1 region died after 10 minutes of ischemia and is followed by 72 hours of reperfusion. However, brain ischemic postconditioning (six cycles of 10 s/10 s reperfusion/re-occlusion) significantly reduced neuronal death. Significant up-regulation of Glutamate transporter-1 was found after 3, 6, 24, 72 hours of reperfusion. The present study showed that ischemic postconditioning decreases cell death and that upregulation of GLT-1 expression may play an important role on this effect.

Transient forebrain or global ischemia induces cell death in vulnerable CA1 pyramidal neurons. A brief period of ischemia, i.e., ischemic preconditioning, affords CA1 neurons robust protection against a subsequent, more prolonged ischemic challenge. Using the four-vessel occlusion model, we established an ischemic preconditioning model in which rodents were subjected to 3 min of sublethal ischemia 48 h before a 15 min lethal ischemia. We showed that preconditioning attenuated the ischemia-induced neural cell death and DNA fragmentation in the hippocampal CA1 region. RT-PCR and western blot analysis showed that preconditioning prior to an ischemic insult significantly increased ASIC 2a mRNA and protein expression in comparison to the ischemic insult alone (p < 0.01). These findings implicate a new role of ASIC 2a on endogenous neuroprotection from ischemic insult.