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Heuristic techniques for maximum likelihood localization of radioactive sources via a sensor network

Nuclear Science and Techniques 2023年第8期34卷 174-193页

作者： Assem Abdelhakim Department of Radiation Engineering National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairo 11787Egypt

Maximum likelihood estimation(MLE)is an effective method for localizing radioactive sources in a given area.However,it requires an exhaustive search for parameter estimation,which is time-consuming.In this study,heuristic techniques were employed to search for radiation source parameters that provide the maximum likelihood by using a network of sensors.Hence,the time consumption of MLE would be effectively reduced.First,the radiation source was detected using the k-sigma method.Subsequently,the MLE was applied for parameter estimation using the readings and positions of the detectors that have detected the radiation source.A comparative study was performed in which the estimation accuracy and time consump-tion of the MLE were evaluated for traditional methods and heuristic techniques.The traditional MLE was performed via a grid search method using fixed and multiple resolutions.Additionally,four commonly used heuristic algorithms were applied:the firefly algorithm(FFA),particle swarm optimization(PSO),ant colony optimization(ACO),and artificial bee colony(ABC).The experiment was conducted using real data collected by the Low Scatter Irradiator facility at the Savannah River National Laboratory as part of the Intelligent radiation Sensing System program.The comparative study showed that the estimation time was 3.27 s using fixed resolution MLE and 0.59 s using multi-resolution MLE.The time consumption for the heuristic-based MLE was 0.75,0.03,0.02,and 0.059 s for FFA,PSO,ACO,and ABC,respectively.The location estimation error was approximately 0.4 m using either the grid search-based MLE or the heuristic-based MLE.Hence,heuristic-based MLE can provide comparable estimation accuracy through a less time-consuming process than traditional MLE.

关键词： Radioactive source Maximum likelihood estimation Multi-resolution MLE k-sigma Firefly algorithm Particle swarm optimization Ant colony optimization Artificial bee colony

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Stereotactic body radiation therapy in patients with hepatocellular carcinoma: A mini-review

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World Journal of Gastrointestinal Oncology 2019年第5期11卷 367-376页

作者： Sabine Gerum Alexandra D Jensen Falk Roeder Department of Radiation Oncology University Hospital LMU Munich Department of Radiation Oncology University Hospital Gie?en and Marburg CCU Molecular radiation Oncology German Cancer Research Center department of Radiotherapy and radiation Oncology Paracelsus Medical University

Stereotactic body radiation therapy(SBRT) is an emerging treatment for hepatocellular carcinoma. This technique results in excellent local control rates with favorable toxicity profile despite being predominantly used in heavily pretreated patients or those unsuitable for other local therapies. SBRT may be used as a sole treatment or in combination with other local therapies as well as a bridging strategy for patient awaiting liver transplants. This brief review describes current practice of SBRT with respect to radiation technique, patient selection and treatment concepts. It summarizes available evidence from retroand prospective studies evaluating SBRT alone, SBRT in combination with other treatments and SBRT compared to other local treatment approaches.

关键词： Hepatocellular carcinoma Stereotactic body radiation therapy Local-ablative treatment Combination approaches Mini-review

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A systematic review on the safety of Psoraleae Fructus:potential risks,toxic characteristics,underlying mechanisms and detoxification methods

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Chinese Journal of Natural Medicines 2022年第11期20卷 805-813页

作者： SHI Zhuo GAO Jing PAN Jinchao ZHANG Zuqi ZHANG Guangchen WANG Yuguang GAO Yue department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China

Psoraleae Fructus(PF)is an important traditional herbal medicine with a long history of clinical application.It is widely used to treat various diseases,such as osteoporosis,leucoderma and diarrhea.As a traditional nontoxic herb,it has aroused worldwide concern about the potential risks due to increasing adverse reaction events.This article reviews the botany,ancient records of medical uses,adverse reactions,toxicological research advance and detoxification methods of PF.According to clinical studies,liver injury is the most predominant in PF-related adverse reactions.The underlying mechanisms include bile acid metabolism and transport disorders,oxidative stress,mitochondrial damage,inhibition of liver cell regeneration and inflammatory reactions.Furthermore,the potential toxins of PF are summarized.Traditional methods of processing and compatibility will provide reference for reducing the toxicity of PF,which requires further research.In sum,this work systematically summarizes the reserach progress on the safety of PF,which will provide comprehensive insights into the toxicity of PF and facilitate its safe use and future development.

关键词： Psoraleae Fructus Toxic characteristics Detoxification compatibility Toxic substances Hepatotoxicity Psoralea corylifolia L.

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3D-printed engineered bacteria-laden gelatin/sodium alginate composite hydrogels for biological detection of ionizing radiation

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Bio-Design and Manufacturing 2023年第4期6卷 439-450页

作者： Ziyuan Chen Jintao Shen Meng Wei Wenrui Yan Qiucheng Yan Zhangyu Li Yaqiong Chen Feng Zhang Lina Du Bochuan Yuan Yiguang Jin department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China

Nuclear safety is a global growing concern,where ionizing radiation(IR)is a major injury factor resulting in serious damage to organisms.The detection of IR is usually conducted with physical dosimeters;however,biological IR detection methods are deficient.Here,a living composite hydrogel consisting of engineered bacteria and gelatin/sodium alginate was 3D-printed for the biological detection of IR.Three strains of PrecA::egfp gene circuit-containing engineered Escherichia coli were constructed with IR-dependent fluorescence,and the DH5αstrain was finally selected due to its highest radiation response and fluorescence.Engineered bacteria were loaded in a series of gelatin/sodium alginate matrix hydrogels with different rheology,3D printability and bacterial applicability.A high-gelatin-content hydrogel containing 10%gelatin/1.25%sodium alginatewas optimal.The optimal living composite hydrogelwas 3D-printedwith the special bioink,which reported significant green fluorescence underγ-ray radiation.The living composite hydrogel provides a biological strategy for the detection of environmental ionizing radiation.

关键词： 3D printing Alginate Engineered bacteria Gelatin Hydrogel Ionizing radiation

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Stereotactic radiotherapy for prostate cancer:A review and future directions

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World Journal of Clinical Oncology 2017年第5期8卷 389-397页

作者： Yusef A Syed Ami K Patel-Yadav Charlotte Rivers Anurag K Singh Department of Radiation Oncology Winship Cancer Institute of Emory University Department of Radiation Oncology University at Buffalo Department of Radiation Oncology Roswell Park Cancer Institute

Prostate cancer affects over 200000 men annually in the United States alone.The role of conventionally fractionated external beam radiation therapy (RT) is well established as a treatment option for eligible prostate cancer patients; however,the use of stereotactic body radiotherapy (SBRT) in this setting is less well defined.Within the past decade,there have been a number of studies investigating the feasibility of SBRT as a potential treatment option for prostate cancer patients.SBRT has been well studied in other disease sites,and the shortened treatment course would allow for greater convenience for patients.There may also be implications for toxicity as well as disease control.In this review we present a number of prospective and retrospective trials of SBRT in the treatment of prostate cancer.We focus on factors such as biochemical progression-free survival,prostate specific antigen (PSA) response,and toxicity in order to compare SBRT to established treatment modalities.We also discuss future steps that the clinical community can take to further explore this new treatment approach.We conclude that initial studies examining the use of SBRT in the treatment of prostate cancer have demonstrated impressive rates of biochemical recurrencefree survival and PSA response,while maintaining a relatively favorable acute toxicity profile,though long-term follow-up is needed.

关键词： Stereotactic body radiotherapy Prostate cancer radiation therapy Hypofractionation Toxicity Stereotactic ablative radiotherapy

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Persea americana attenuates inflammatory response associated with hyperlipidemia in ovariectomized and irradiated rats by regulating MMP-3/TIMP-1 levels

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Asian Pacific Journal of Tropical Biomedicine 2022年第9期12卷 374-382页

作者： Dina F.Elmaghraby Fatma A.M.Salem Esraa S.A.Ahmed department of Health radiation Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt department of Chemistry Faculty of ScienceHelwan UniversityCairoEgypt radiation Biology Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt

Objective:To explore the effect of Persea americana supplementation on inflammation,oxidative stress,and lipid profiles in ovariectomized rats fed with a high-fat diet and exposed to radiation.Methods:The control group was sham operated,while groups 2-5 were ovariectomized and fed a high-fat diet.Groups 4 and 5 were exposed toγ-radiation(1 Gy/week for 5 weeks)after ovariectomy.Groups 3 and 5 were treated with 1 mL/250 g/day of Persea americana for one month.Serum levels of estrogen,alanine aminotransferase,aspartate aminotransferase,cholesterol,triglycerides and lipoproteins were measured.Additionally,hepatic oxidative stress,inflammatory and fibrogenic markers were evaluated.Results:Persea americana treatment reduced the oxidative stress markers as well as the levels of triglyceride,total cholesterol,and low-density lipoprotein cholesterol,which in turn lowered hepatic fat accumulation.Moreover,it suppressed hepatic inflammatory mediators(interleukin-6,tumor necrosis factor-α,and C-reactive protein)and downregulated pro-fibrogenic markers(transforming growth factor-βand tissue inhibitor of metalloproteinase-1).Conclusions:Persea americana provides protection against ovariectomy,and gamma radiation-mediated hepatic inflammation not only through its antioxidant,anti-inflammatory,lipid-lowering effect but also by modulating the fibrogenic markers.

关键词： Persea americana γ-radiation Postmenopausal Oxidative stress Lipid Ovariectomy Hepatic inflammation Fibrogenic Rat

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Strategies to tackle the challenges of external beam radiotherapy for liver tumors

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World Journal of Hepatology 2017年第14期9卷 645-656页

作者： Michael I Lock Jonathan Klein Hans T Chung Joseph M Herman Edward Y Kim William Small Nina A Mayr Simon S Lo Department of Radiation Oncology London Regional Cancer ProgramUniversity of Western Ontario Department of Radiation Oncology Odette Cancer CentreSunnybrook Health Sciences Centre Department of Radiation Oncology the University of Texas Department of Radiation Oncology University of Washington School of Medicine Department of Radiation Oncology Loyola University Medical Center

Primary and metastatic liver cancer is an increasingly common and difficult to control disease entity.radiation offers a non-invasive treatment alternative for these patients who often have few options and a poor prognosis.However,the anatomy and aggressiveness of liver cancer poses significant challenges such as accurate localization at simulation and treatment,management of motion and appropriate selection of dose regimen.This article aims to review the options available and provide information for the practical implementation and/or improvement of liver cancer radiation programs within the context of stereotactic body radiotherapy and image-guided radiotherapy guidelines.Specific patient inclusion and exclusion criteria are presented given the significant toxicity found in certain sub-populations treated with radiation.Indeed,certain sub-populations,such as those with tumor thrombosis or those with larger lesions treated with transarterial chemoembolization,have been shown to have significant improvements in outcome with the addition of radiation and merit special consideration.Implementing a liver radiation programrequires three primary challenges to be addressed:(1) immobilization and motion management;(2) localization;and(3) dose regimen and constraint selection.Strategies to deal with motion include simple internal target volume(ITV) expansions,non-gated ITV reduction strategies,breath hold methods,and surrogate marker methods to enable gating or tracking.Localization of the tumor and organs-at-risk are addressed using contrast infusion techniques to take advantage of different normal liver and cancer vascular anatomy,imaging modalities,and margin management.Finally,a dose response has been demonstrated and dose regimens appear to be converging.A more uniform approach to treatment in terms of technique,dose selection and patient selection will allow us to study liver radiation in larger and,hopefully,multicenter randomized studies.

关键词： Hepatocellular 癌肝转移 4DCT 指导图象的放射疗法 Stereotactic 身体放射治疗

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Behavioral Abnormality along with NMDAR-related CREB Suppression in Rat Hippocampus after Shortwave Exposure

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Biomedical and Environmental Sciences 2019年第3期32卷 189-198页

作者： YU Chao BAI Yan Xin XU Xin Ping GAO Ya Bing HAO Yan Hui WANG Hui TAN Sheng Zhi LI Wen Chao ZHANG Jing YAO Bin Wei DONG Ji ZHAO Li PENG Rui Yun department of Experimental Pathology Beijing Institute of Radiation Medicine

Objective To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms. Methods One hundred Wistar rats were randomly divided into four groups(25 rats per group) and exposed to 27 MHz continuous shortwave at a power density of 5, 10, or 30 m W/cm^2 for 6 min once only or underwent sham exposure for the control. The spatial learning and memory, electroencephalogram(EEG), hippocampal structure and Nissl bodies were analysed. Furthermore, the expressions of N-methyl-D-aspartate receptor(NMDAR) subunits(NR1, NR2 A, and NR2 B), c AMP responsive element-binding protein(CREB) and phosphorylated CREB(p-CREB) in hippocampal tissue were analysed on 1, 7, and 14 days after exposure. Results The rats in the 10 and 30 m W/cm^2 groups had poor learning and memory, disrupted EEG oscillations, and injured hippocampal structures, including hippocampal neurons degeneration, mitochondria cavitation and blood capillaries swelling. The Nissl body content was also reduced in the exposure groups. Moreover, the hippocampal tissue in the 30 m W/cm^2 group had increased expressions of NR2 A and NR2 B and decreased levels of CREB and p-CREB. Conclusion Shortwave exposure(27 MHz, with an average power density of 10 and 30 m W/cm^2) impaired rats' spatial learning and memory and caused a series of dose-dependent pathophysiological changes. Moreover, NMDAR-related CREB pathway suppression might be involved in shortwave-induced structural and functional impairments in the rat hippocampus.

关键词： Shortwave exposure Learning and memory Hippocampus NMDAR CREB

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Role of adjuvant chemoradiotherapy and chemotherapy in patients with resected gallbladder carcinoma: a multiinstitutional analysis (KROG 19-04)

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Cancer Biology & Medicine 2022年第6期19卷 931-944页

作者： Sung Uk Lee Jinsil Seong Tae Hyun Kim Jung Ho Im Woo Chul Kim Kyubo Kim Hae Jin Park Tae Gyu Kim Youngkyong Kim Bae Kwon Jeong Jin Hee Kim Byoung Hyuck Kim Taek-Keun Nam Center for Proton Therapy and Center for Liver and Pancreatobiliary Cancer National Cancer CenterGoyang 10408Korea Department of Radiation Oncology Yonsei Cancer CenterYonsei University College of MedicineSeoul 03722Korea Department of Radiation Oncology CHA Bundang Medical CenterCHA University School of MedicineSeongnam 13497Korea Department of Radiation Oncology Inha University HospitalInha University School of MedicineIncheon 22332Korea Department of Radiation Oncology Ewha Womans University Mokdong HospitalEwha Womans University College of MedicineSeoul 07985Korea Department of Radiation Oncology Hanyang University Medical CenterHanyang University College of MedicineSeoul 04763Korea Department of Radiation Oncology Samsung Changwon HospitalSungkyunkwan University School of MedicineChangwon 51353Korea Department of Radiation Oncology Kyung Hee University HospitalKyung Hee University College of MedicineSeoul 02447Korea Department of Radiation Oncology Gyeongsang National University HospitalGyeongsang National University College of MedicineJinju 52727Korea Department of Radiation Oncology Dongsan Medical CenterKeimyung University School of MedicineDaegu 41931Korea Department of Radiation Oncology Seoul Metropolitan Government Seoul National University Boramae Medical CenterSeoul 07061Korea Department of Radiation Oncology Chonnam National University Hwasun HospitalChonnam National University College of MedicineHwasun 58128Korea

Objective:The effectiveness of adjuvant treatments for resected gallbladder carcinoma(GBC)has remained unclear due to lack of randomized controlled trials;thus,the aim of present study was to evaluate the role of adjuvant treatments,including chemoradiotherapy(CRT)and/or chemotherapy(CTx),in patients with resected GBC.Methods:A total of 733 GBC patients who received curative-intent surgical resection were identified in a multi-institutional database.Of 733 patients,372(50.8%)did not receive adjuvant treatment,whereas 215(29.3%)and 146(19.9%)received adjuvant CTx and CRT,respectively.The locoregional recurrence-free survival(LRFS),recurrence-free survival(RFS),and overall survival(OS)of the adjuvant treatment groups were compared according to tumor stage(stage II vs.stage III–IV).Results:In stage II disease(n=381),the 5-year LRFS,RFS,and OS were not significantly different among the no-adjuvant therapy,CTx,and CRT groups,and positive resection margin,presence of perineural invasion,and Nx classification were consistently associated with worse LRFS,RFS,and OS in the multivariate analysis(P<0.05).For stage III–IV(n=352),the CRT group had significantly higher 5-year LRFS,RFS,and OS than the no-adjuvant therapy and CTx groups(67.8%,45.2%,and 56.9%;37.9%,28.8%,and 35.4%;and 45.0%,30.0%,and 45.7%,respectively)(P<0.05).Conclusions:CRT has value as adjuvant treatment for resected GBC with stage III–IV disease.Further study is needed for stage II disease with high-risk features.

关键词： Gallbladder cancer adjuvant treatment chemoradiotherapy locoregional recurrence-free survival overall survival

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Effects of Electromagnetic radiation on Autophagy and its Regulation

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Biomedical and Environmental Sciences 2018年第1期31卷 57-65页

作者： HAO Yan Hui ZHAO Li PENG Rui Yun department of Experimental Pathology Beijing Institute of Radiation Medicine

With the ever increasing application of electronic technology,our exposure to artificial electromagnetic energy is also rapidly increasing.Electromagnetic radiation(EMR)is the fourth largest source of pollution,after air,water,and noise^([1]).All populations are now exposed to varying degrees of EMR,and this poses a serious public health threat.The human level of exposure to EMR will continue to increase as technology advances and becomes

关键词： EMR Effects of Electromagnetic radiation on Autophagy and its Regulation ATG

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