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Contribution of Bone Scintigraphy in the Metastatic Extension Assessment of Prostate Cancer: A Study of 288 Cases in the Nuclear Medicine Department of Idrissa Pouye General Hospital, Dakar
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作者 El Hadji Amadou Lamine Bathily Ousseynou Diop +7 位作者 Mamoudou Salif Djigo Gora Thiaw Kalidou Gueye Mohamed Chekhma Olatounde Herbert Fachinan Boucar Ndong Omar Ndoye Mamadou Mbodj 《Open Journal of Biophysics》 2024年第2期79-98,共20页
Introduction: Prostate cancer is the most frequently diagnosed male malignancy and the fifth leading cause of cancer death in men worldwide. Since the advent of screening methods such as Prostate Specific Antigen (PSA... Introduction: Prostate cancer is the most frequently diagnosed male malignancy and the fifth leading cause of cancer death in men worldwide. Since the advent of screening methods such as Prostate Specific Antigen (PSA) assay, digital rectal examination (DRE) and prostate biopsy, its incidence has increased significantly. The aim of our study was to analyse aspects of bone scintigraphy (BS) as part of the metastatic extension assessment of prostate cancer in Senegal. Patients and Methods: This was a retrospective descriptive and analytical study, running from January 1<sup>er</sup> 2022 to August 31 2023. Patients with histologically confirmed prostate cancer were included. Whole-body scans (WBS) were performed using a dual-head SPECT gamma camera (Mediso Nucline TM Spirit DH-V type), 3 hours after intravenous injection of 8 MBq/kg (555 to 740 MBq) of <sup>99m</sup>Tc-HMDP. Results: A total of 288 patients with a mean age of 68.37 ± 7.79 years were included. The median total PSA level was 97.6 ng/ml, with 144 patients having a level greater than or equal to 20 ng/ml. All patients had adenocarcinoma, and the Gleason score was available in 202 (70.13%) patients, 75.75% of whom had a score greater than or equal to 7. BS was contributory in 70.48% of cases, with 30.90% positive and 39.58% negative. The result was inconclusive in 85 patients (29.51%). The mean PSA for patients with a positive scan was 190.2 ng/ml and 40.6 ng/ml for those with a negative scan. Multiple metastatic lesions predominated (87.35% of cases). Metastatic lesions occurred preferentially in the axial skeleton, with a proportion of 68% versus 32% in the appendicular skeleton. Classification of bone metastases according to the SOLOWAY score revealed grade I (62.07%), grade II (35.63%) and grade IV (2.30%). Conclusion: In Senegal, prostate cancer is generally diagnosed in men of advanced age. The presence of bone metastases is frequent in its evolution, transforming a curable localized disease into a generalized disease with a compromised prognosis. Bone scintigraphy remains an essential part of the initial work-up and evaluation of response to treatment. 展开更多
关键词 Prostate Cancer Bone Metastasis Bone Scintigraphy Senegal
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Spark plasma sintering of tungsten-based WTaVCr refractory high entropy alloys for nuclear fusion applications 被引量:1
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作者 Yongchul Yoo Xiang Zhang +4 位作者 Fei Wang Xin Chen Xing-Zhong Li Michael Nastasi Bai Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期146-154,共9页
W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a po... W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRD),energy-dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSD) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C. 展开更多
关键词 refractory high entropy alloy plasma-facing material fusion reactor spark plasma sintering
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Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations 被引量:1
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作者 Xiang Meng Pierre Désesquelles Lejin Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期433-448,共16页
The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this pap... The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)calculations.The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation.The meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain reactivity.The C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily broken.It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring separation.The decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons. 展开更多
关键词 Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism
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Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism 被引量:1
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作者 Yujie Yang Xinyi Li +7 位作者 Jiaying Lu Jingjie Ge Mingjia Chen Ruixin Yao Mei Tian Jian Wang Fengtao Liu Chuantao Zuo 《Neural Regeneration Research》 SCIE CAS 2025年第1期93-106,共14页
Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.... Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders. 展开更多
关键词 aromatic amino acid decarboxylase brain imaging dopamine transporter Parkinson’s disease PARKINSONISM positron emission tomography presynaptic dopaminergic function vesicle monoamine transporter type 2
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Increasing the Efficiency and Level of Environmental Safety of Pro-Environmental City Heat Supply Technologies by Low Power Nuclear Plants
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作者 Vladimir Kravchenko Igor Kozlov +3 位作者 Volodymyr Vashchenko Iryna Korduba Andrew Overchenko Serhii Tsybytovskyi 《World Journal of Nuclear Science and Technology》 CAS 2024年第2期107-117,共11页
In connection with the current prospect of decarbonization of coal energy through the use of small nuclear power plants (SNPPs) at existing TPPs as heat sources for heat supply to municipal heating networks, there is ... In connection with the current prospect of decarbonization of coal energy through the use of small nuclear power plants (SNPPs) at existing TPPs as heat sources for heat supply to municipal heating networks, there is a technological need to improve heat supply schemes to increase their environmental friendliness and efficiency. The paper proves the feasibility of using the heat-feeding mode of ASHPs for urban heat supply by heating the network water with steam taken from the turbine. The ratio of electric and thermal power of a “nuclear” combined heat and power plant is given. The advantage of using a heat pump, which provides twice as much electrical power with the same heat output, is established. Taking into account that heat in these modes is supplied with different potential, the energy efficiency was used to compare these options. To increase the heat supply capacity, a scheme with the use of a high-pressure heater in the backpressure mode and with the heating of network water with hot steam was proposed. Heat supply from ASHPs is efficient and environmentally friendly even in the case of significant remoteness of heat consumers. 展开更多
关键词 Low-Capacity Nuclear Power Plants Environmental Friendliness of the Thermal Power Generation Mode Heat Generation Condensation Mode Heat Supply
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Positron emission tomography/computed tomography in risk-factornegative young female with malignant pleural mesothelioma:A case report and review of literature
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作者 Aikedan Aisikaer Mo-Mo Sun Jie Shen 《World Journal of Clinical Cases》 2025年第32期95-102,共8页
BACKGROUND Malignant pleural mesothelioma(MPM),a rare aggressive malignancy,is primarily caused by asbestos exposure.MPM typically affects older adults(median age,76 years),is uncommon in those under age 50 years and ... BACKGROUND Malignant pleural mesothelioma(MPM),a rare aggressive malignancy,is primarily caused by asbestos exposure.MPM typically affects older adults(median age,76 years),is uncommon in those under age 50 years and shows male predominance.Based on the American Society of Clinical Oncology guidelines,F-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT)is essential for initial MPM staging.Integrating quantitative FDG metabolic data with computed tomography(CT)anatomy optimizes biopsy accuracy and staging.CASE SUMMARY A 21-year-old female college student presented with fever(peak 38.4°C),cough,and white mucoid sputum after cold exposure.Initial evaluation revealed elevated C-reactive protein[C-reactive protein(CRP);65.52 mg/L]and Mycoplasma pneumoniae IgM.Despite resolution of fever following a 14-day moxifloxacin regimen,persistent cough prompted chest CT,which demonstrated left pleural mass-like thickenings.Levofloxacin therapy for 2 weeks failed to alleviate symptoms,accompanied by 2.5-kg weight loss over 1 month.Re-evaluation showed rising CRP(88.87 mg/L)with stable CT lesions,and negative T-cell spot test for tuberculosis and tumor markers.Contrast-enhanced CT revealed heterogeneously enhancing masses,while PET/CT detected two broad-based pleural lesions with intense FDG avidity.CT-guided biopsy confirmed epithelioid MPM.Thoracoscopy exposed diffuse fragile,hemorrhagic nodules implanting on diaphragmatic and parietal pleura,confirming metastatic MPM with partial resection performed.This presentation challenges conventional imaging paradigms of MPM,underscoring its diagnostic complexity.CONCLUSION MPM should still be considered an important differential diagnosis in young patients presenting with solitary pleural masses and no history of typical asbestos exposure.F-18 FDG PET/CT,while serving as an essential component of initial staging for MPM,has some inherent limitations. 展开更多
关键词 Pleural neoplasms Malignant pleural mesothelioma Positron emission tomography computed tomography F-18 fluorodeoxyglucose Case report
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Steady-state and transient investigation of a small pressurized water reactor ACPR50S for different ATFs based on Bamboo-C code
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作者 Kun Zhuang Ying-Zhen Wang +3 位作者 Li-Na Deng Yong-Zhan Wang Wen Shang Si-Peng Wang 《Nuclear Science and Techniques》 2025年第1期192-206,共15页
Small modular reactors have received widespread attention owing to their inherent safety,low investment,and flexibility.Small pressurized water reactors(SPWRs)have become important candidates for SMRs owing to their h... Small modular reactors have received widespread attention owing to their inherent safety,low investment,and flexibility.Small pressurized water reactors(SPWRs)have become important candidates for SMRs owing to their high technological maturity.Since the Fukushima accident,research on accident-tolerant fuels(ATFs),which are more resistant to serious accidents than conventional fuels,has gradually increased.This study analyzes the neutronics and thermal hydraulics of an SPWR(ACPR50S)for different ATFs,BeO+UO_(2)−SiC,BeO+UO_(2)−FeCrAl,U_(3)Si_(2)−SiC,and U_(3)Si_(2)−FeCrAl,based on a PWR fuel management code,the Bamboo-C deterministic code.In the steady state,the burnup calculations,reactivity coefficients,power and temperature distributions,and control rod reactivity worth were studied.The transients of the control rod ejection accident for the two control rods with the maximum and minimum reactivity worth were analyzed.The results showed that 5%B-10 enrichment in the wet annular burnable absorbers assembly can effectively reduce the initial reactivity and end-of-life reactivity penalty.The BeO+UO2−SiC core exhibited superior neutronic characteristics in terms of burnup and negative temperature reactivity compared with the other three cases owing to the strong moderation ability of BeO+UO_(2)and low neutron absorption of SiC.However,the U_(3)Si_(2)core had a marginally better power-flattening effect than BeO+UO_(2),and the differential worth of each control rod group was similar between different ATFs.During the transient of a control rod ejection,the changes in the fuel temperature,coolant temperature,and coolant density were similar.The maximum difference was less than 10℃ for the fuel temperature and 2℃ for the coolant temperature. 展开更多
关键词 ACPR50S Small pressurized water reactor ATF STEADY Transient
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Progress in the application of fludeoxyglucose positron emission tomography computed tomography in biliary tract cancer
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作者 Jia-Xin Yin Xin Fan +2 位作者 Qiao-Liang Chen Jing Chen Jian He 《World Journal of Hepatology》 2025年第5期32-44,共13页
Biliary tract cancer(BTC)is a group of heterogeneous sporadic diseases,including intrahepatic,hilar,and distal cholangiocarcinoma,as well as gallbladder cancer.BTC is characterized by high invasiveness and extremely p... Biliary tract cancer(BTC)is a group of heterogeneous sporadic diseases,including intrahepatic,hilar,and distal cholangiocarcinoma,as well as gallbladder cancer.BTC is characterized by high invasiveness and extremely poor prognosis,with a global increased incidence due to intrahepatic cholangiocarcinoma(ICC).The 18Ffludeoxyglucose positron emission tomography(PET)computed tomography(18F-FDG PET/CT)combines glucose metabolic information(reflecting the glycolytic activity of tumor cells)with anatomical structure to assess tumor metabolic heterogeneity,systemic metastasis,and molecular characteristics noninvasively,overcoming the limitations of traditional imaging in the detection of micrometastases and recurrent lesions.18F-FDG PET/CT offers critical insights in clinical staging,therapeutic evaluation,and prognostic prediction of BTC.This article reviews research progress in this field over the past decade,with a particular focus on the advances made in the last 3 years,which have not been adequately summarized and recognized.The research paradigm in this field is shifting from qualitative to quantitative studies,and there have been significant breakthroughs in using 18F-FDG PET/CT metabolic information to predict gene expression in ICC.Radiomics and deep learning techniques have been applied to ICC for prognostic prediction and differential diagnosis.Additionally,PET/magnetic resonance imaging is increasingly demonstrating its value in this field. 展开更多
关键词 Biliary tract cancer Positron radiopharmaceuticals Fluorodeoxyglucose positron emission tomography Radiomics Positron emission tomography computed tomography Positron emission tomography magnetic resonance imaging
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Intrinsic gallium-68 labeling of nanoclays for in vivo tracking
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作者 Nian Liu Tingting Wang +1 位作者 Jian Li Xinhui Su 《Journal of Pharmaceutical Analysis》 2025年第1期281-283,共3页
Nanoclays have large specific surface area,good adsorption properties,and biocompatibility that have great potential for drug delivery applications[1].Evaluating the in vivo metabolic pathways of nanoclays can help to... Nanoclays have large specific surface area,good adsorption properties,and biocompatibility that have great potential for drug delivery applications[1].Evaluating the in vivo metabolic pathways of nanoclays can help to understand their pharmacodynamic sites and the toxicological effects caused by their in vivo retention time[2]. 展开更多
关键词 BIOCOMPATIBILITY specific surface area adsorption properties pharmacodynamic sites intrinsic gallium labeling NANOCLAYS toxicological effects vivo tracking
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Radiosynthesis and preclinical evaluation of[^(18)F]AlF-labeled HBED-CC-FAPI derivatives for imaging of cancer-associated fibroblasts
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作者 Haiyan Hong Yan Zhang +3 位作者 Jinping Qiao Wensheng Zhang Lin Zhu Jiehua Xu 《Journal of Pharmaceutical Analysis》 2025年第2期484-487,共4页
Fibroblast activation protein(FAP)is overexpressed in cancer-associated fibroblasts across various cancer types.Numerous radiolabeled FAP inhibitors(FAPIs)(Fig.S1A)currently under clinical investigation have shown rem... Fibroblast activation protein(FAP)is overexpressed in cancer-associated fibroblasts across various cancer types.Numerous radiolabeled FAP inhibitors(FAPIs)(Fig.S1A)currently under clinical investigation have shown remarkable potential in cancer theranostics. 展开更多
关键词 RADIOSYNTHESIS cancer theranostics clinical investigation cancer associated fibroblasts preclinical evaluation f alf labeled hbed cc fapi derivatives fibroblast activation IMAGING
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Overview of the Impact of PSMA PET on the Management of Prostate Cancer Patients
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作者 Jinyu Zhang Xin Dai +3 位作者 Xinyi Ren Yuxin Zheng Jia Liu Gang Cheng 《Journal of Biosciences and Medicines》 2025年第2期169-189,共21页
Prostate cancer (PCa) is the second most common type of cancer among men worldwide and one of the leading causes of cancer-related deaths. According to data from the World Health Organization (WHO), this cancer causes... Prostate cancer (PCa) is the second most common type of cancer among men worldwide and one of the leading causes of cancer-related deaths. According to data from the World Health Organization (WHO), this cancer causes hundreds of thousands of new cases and tens of thousands of male deaths globally each year. The incidence of PCa varies across different regions and populations, generally being higher in developed countries. This disparity may be attributed to lifestyle factors and the widespread availability of screening and diagnostic technologies. Prostate-specific membrane antigen (PSMA) is a membrane-bound enzyme predominantly expressed in prostate tissue and PCa cells, with lower expression in normal tissues. This high expression makes PSMA a critical target for the diagnosis and treatment of PCa, particularly in the field of molecular imaging and radiopharmaceutical therapy. Recently, various studies have emerged on radiopharmaceuticals developed based on PSMA ligands, which can be used to specifically identify and locate PCa cells. Research on the radiomics of these novel drugs has also been updated. This article will discuss the role and limitations of PSMA PET in the diagnosis and management of PCa treatment. 展开更多
关键词 PSMA PET Prostate Cancer Molecular Imaging Radioligand Therapy
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Changing paradigms in evaluating adrenal incidentalomas:Bayesian evaluation of[^(18)F]Fluorodeoxyglucose positron emission tomography use,honed on adrenocortical carcinoma
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作者 Ioannis Ilias Georgios Meristoudis 《World Journal of Clinical Oncology》 2025年第6期128-133,共6页
We present the diagnostic performance of[18F]Fluorodeoxyglucose positron emission tomography(FDG PET)for adrenal incidentalomas based on lesion size and unenhanced computed tomography(CT)density in Hounsfield units(HU... We present the diagnostic performance of[18F]Fluorodeoxyglucose positron emission tomography(FDG PET)for adrenal incidentalomas based on lesion size and unenhanced computed tomography(CT)density in Hounsfield units(HU),following current literature and guidelines.A 20 HU cutoff can be applied to differentiate potentially benign from malignant lesions,particularly in ruling in or out adrenocortical carcinoma.While FDG PET provides valuable metabolic information,its likelihood ratios for a positive(LR+)or negative(LR-)result do not exceed the robust diagnostic thresholds of>10.0 or<0.1,respectively.This suggests that positron emission tomography alone is insufficient for definitive characterization and should be integrated with CT or magnetic resonance imaging to leverage their complementary anatomical and functional imaging strengths for optimal diagnostic accuracy. 展开更多
关键词 Adrenal gland neoplasms DIAGNOSIS EPIDEMIOLOGY Positron emission tomography Bayes theorem
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Potential of mesenchymal stem cell-derived exosomes in the treatment of androgenetic alopecia
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作者 Ramya Lakshmi Rajendran Byeong-Cheol Ahn Prakash Gangadaran 《World Journal of Stem Cells》 2025年第5期155-158,共4页
Exosomes are derived from various cell types,including mesenchymal stem cells(MSCs),and play a crucial role in cellular communication,significantly influencing tissue repair and regeneration and facilitating the heali... Exosomes are derived from various cell types,including mesenchymal stem cells(MSCs),and play a crucial role in cellular communication,significantly influencing tissue repair and regeneration and facilitating the healing process.Thus,insights into the functions of exosomes present novel opportunities in regenerative therapy.This article aims to discuss the promising potential of exosomes derived from human adipose-derived MSCs in treating androgenetic alopecia.This study aims to highlight how exosomes derived from human adipose-derived MSCs enhance dermal papilla cell proliferation through the Wnt/β-catenin pathway,counteracting the effects of excessive dihydrotestosterone and offering a novel approach for treating androgenetic alopecia. 展开更多
关键词 EXOSOME Mesenchymal stem cells Hair regrowth Dermal papilla cell WNT/Β-CATENIN
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Challenges in the diagnosis of esophageal cancer with intramural gastric metastasis:Two case reports
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作者 Hao-Ying Wang Chun Song +4 位作者 Jing Ma Hai-Qing Sun Peng Yuan Zhen-Xiong Liu Wei-Jia Dou 《World Journal of Gastrointestinal Oncology》 2025年第8期412-419,共8页
BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a prevalent gastrointestinal malignancy associated with significant morbidity and mortality rates.Tumor metastasis leads to a poor prognosis for patients.Intramura... BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a prevalent gastrointestinal malignancy associated with significant morbidity and mortality rates.Tumor metastasis leads to a poor prognosis for patients.Intramural gastric metastasis(IGM),is an uncommon pathway of ESCC metastasis,and is more likely to occur when in situ tumor cells show deep infiltration.In this study,we describe the diagnosis and management of two rare cases of T1-stage ESCC with IGM in clinical practice.CASE SUMMARY Case 1:In this patient,the submucosal tumor-like lesion was initially thought to be a gastrointestinal stromal tumor.T1-stage ESCC was then diagnosed by gastroendoscopy during subsequent evaluation.The lesion was finally confirmed to be submucosal metastasis of ESCC following pathological analysis.The patient has been receiving treatment for over seven months,with an encouraging outcome.Case 2:In this patient,the initial diagnostic phase showed esophageal and gastric lesions which were classified as two distinct conditions:Early-stage ESCC and a gastrointestinal stromal tumor,respectively.However,postoperative pathology revealed ESCC with IGM.The patient received adjuvant chemotherapy following surgical intervention.Regrettably,the patient was lost to follow-up shortly after surgery.CONCLUSION The occurrence of IGM in T1-stage ESCC is rare.IGM should be taken into consideration when diagnosing submucosal tumor-like lesions to prevent misdiagnosis and missed diagnosis. 展开更多
关键词 Esophageal squamous cell carcinoma Intramural gastric metastasis Submucosal tumor-like lesions PROGNOSIS Case report
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Quality Control and Optimization of Computed Tomography Dose Index Volume (CTDIvol) of LightSpeed RT16 Xtra CT Scanner
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作者 Umme Sadia Binte Kashem Shirin Akter +4 位作者 Afroza Shelley Rajada Khatun Ashrafun Nahar Monika Laila Sharmin Md. Anwarul Islam 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2025年第1期1-13,共13页
Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed To... Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed Tomography (CT) system of LightSpeed RT16 Xtra CT scanner. Quality control was done using a vendor-provided QA Phantom, and the six aspects of image quality were measured. For CT dosimetry, Computed Tomography Dose index volume (CTDIvol) was performed using Computed Tomography Dose Index (CTDI) Phantom. CTDI Phantom consists of three parts: Pediatric Head, Adult Head, and Adult Body Phantom. A 10 cm long pencil ion chamber DCT-10 was used to measure the dose at different positions inside the CTDI Phantom. Data were collected using MagicMax Universal software. For dose estimation of the CTDIvol Report of AAPM Task Group, 96 and 111 formalisms were used. For Pediatric Head, Adult Head, and Adult Body Phantom the measured CIDIvol was 61.04 mGy, 48.11 mGy, and 18.08 mGy respectively. The study has shown deviations of 7%, 15%, and 19% between estimated and console-displayed doses for Pediatric Head, Adult Head, and Adult Body scan techniques respectively. The six aspects of image quality measured by QA Phantom were found to be compatible with the specifications of the machine and CTDIvol measured by CTDI Phantom were found within a tolerance limit of ±20%. Hence, the QC and dosimetry of the mentioned machine are within the limit. 展开更多
关键词 Quality Control CTDIvol LightSpeed RT16 Xtra CT Scanner PHANTOM
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A two-sample Mendelian randomization study on the relationship of body weight,body mass index,and waist circumference with cardiac arrest
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作者 Tingting Xu Shaokun Wang +2 位作者 Liqiang Zhao Jiawen Wang Jihong Xing 《World Journal of Emergency Medicine》 2025年第2期129-135,共7页
BACKGROUND:This study aims to explore the causal relationship of body weight,body mass index(BMI),and waist circumference (WC) with the risk of cardiac arrest (CA) using two-sample Mendelian randomization (MR).METHODS... BACKGROUND:This study aims to explore the causal relationship of body weight,body mass index(BMI),and waist circumference (WC) with the risk of cardiac arrest (CA) using two-sample Mendelian randomization (MR).METHODS:Data were summarized using genome-wide association studies (GWAS).Twosample MR analyses were performed using the inverse variance weighting (IVW) method,the weighted median method,and the MR-Egger analysis.Heterogeneity test and sensitivity analysis were performed using Cochran’s Q test and the leave-one-out method,respectively.The Steiger test was used to detect reverse causality.Bayesian model-averaged MR was used to identify the most influential risk factors.RESULTS:A total of 13 GWAS data were collected for BMI,body weight and WC.IVW analyses showed a positive correlation of body weight,BMI,and WC with CA (all OR>1 and P<0.05),with MR-Egger and weighted median methods confirming the IVW findings.No horizontal pleiotropy or heterogeneity was observed.Sensitivity analysis indicated that no single nucleotide polymorphism(SNP) caused significant changes in overall causality.Bayesian model-averaged MR was also used to rank causality based on marginal inclusion probability (MIP),and the corresponding modelaveraged causal estimate (MACE) were confirmed,which indicated that WC (GWAS ID:ukb-b-9405)was the highest-ranked risk factor (MIP=0.119,MACE=0.011);its posterior probability was 0.057.A total of 14 sex-specific GWAS data on weight,BMI,and WC were analyzed in relationship with CA,and the MR results showed no significant effects of sex-specific factors.CONCLUSION:Body weight,BMI,and WC are causally associated with an increased risk of CA,with WC identified as the most important risk factor. 展开更多
关键词 Body weight Body mass index Waist circumference Cardiac arrest Mendelian randomization
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Validation and application of a coupled xenon-transport and reactor dynamic model of Molten-salt reactor experiment
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作者 Jia-Qi Chen Caleb S.Brooks 《Nuclear Science and Techniques》 2025年第6期156-175,共20页
Liquid-fueled molten-salt reactors have dynamic features that distinguish them from solid-fueled reactors,such that conventional system-analysis codes are not directly applicable.In this study,a coupled dynamic model ... Liquid-fueled molten-salt reactors have dynamic features that distinguish them from solid-fueled reactors,such that conventional system-analysis codes are not directly applicable.In this study,a coupled dynamic model of the Molten-Salt Reactor Experiment(MSRE)is developed.The coupled model includes the neutronics and single-phase thermal-hydraulics modeling of the reactor and validated xenon-transport modeling from previous studies.The coupled dynamic model is validated against the frequency-response and transient-response data from the MSRE.The validated model is then applied to study the effects of xenon and void transport on the dynamic behaviors of the reactor.Plant responses during the unique initiating events such as off-gas system blockages and loss of circulating voids are investigated. 展开更多
关键词 Nuclear-reactor dynamics Molten-salt reactor experiment Frequency response Molten-salt reactor XENON
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Dopamine receptor D1-mediated suppression of liver fibrosis via Hippo/Yes-associated protein 1 signaling in levodopa treatment
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作者 Hai-Yan Wang Man-Man Qi +2 位作者 Kai Zhang Yu-Zhao Zhu Jian Zhang 《World Journal of Gastroenterology》 2025年第34期108-118,共11页
BACKGROUND Yes-associated protein 1(YAP1),a downstream transcriptional coactivator regulated by the Hippo signaling pathway,has been shown to be involved in liver fibrosis.YAP activity is modulated by G-protein couple... BACKGROUND Yes-associated protein 1(YAP1),a downstream transcriptional coactivator regulated by the Hippo signaling pathway,has been shown to be involved in liver fibrosis.YAP activity is modulated by G-protein coupled receptors,including Gαs-coupled protein dopamine receptor D1(DRD1).Levodopa,a dopamine precursor,activates DRD1 on cell surface,triggering its downstream signaling pathway.AIM To investigate the therapeutic effect of levodopa and the downstream mechanism on carbon tetrachloride(CCl_(4))-induced liver fibrosis,including liver DRD1 expression.METHODS SD rats were intraperitoneally injected with 40%CCl_(4)for 8 weeks to induce liver fibrosis,followed by treatment with varying doses of levodopa for 2 weeks.Serum aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels were measured,and liver pathology was assessed using hematoxylin and eosin and Masson's staining.Alpha-smooth muscle actin(α-SMA)content,along with the expressions of DRD1,YAP,and phosphorylated protein,was analyzed by Western blot,immunohistochemistry,and reverse transcription-quantitative real-time polymerase chain reaction.RESULTS Compared with the controls,levodopa-treated rats showed a decrease in the proportion of collagen in the liver and a recovery from liver fibrosis(P=0.0007).Western blot and immunohistochemistry indicated that DRD1 was upregulated in the fibrotic liver of rats treated with levodopa,showing an increase in DRD1 Level(P<0.0001).In addition,the upregulation of DRD1 activated the Hippo signaling pathway,manifested as increased YAP phosphorylation(P<0.05).CONCLUSION This was the first study to demonstrate that levodopa attenuates CCl_(4)-induced liver fibrosis by inhibiting the Hippo/YAP signaling pathways. 展开更多
关键词 LEVODOPA Liver fibrosis Yes1 associated transcriptional regulator Hippo/Yes-associated protein 1 signaling pathway Dopamine receptor D1
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Mechanistic switch in corrosion behavior of magnesium alloy diamond lattice structures induced by argon plasma treatment
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作者 Viviana M.Posadaa Alexandru Marin +2 位作者 Tonny Naranjo Juan Ramírez Patricia Fernández-Morales 《Journal of Magnesium and Alloys》 2025年第1期101-119,共19页
Advancing 3D magnesium(Mg)development beyond current limitations requires controlling Mg alloy degradation in pre-designed,low-dimension architectures.This study reveals a mechanistic switch in the corrosion behavior ... Advancing 3D magnesium(Mg)development beyond current limitations requires controlling Mg alloy degradation in pre-designed,low-dimension architectures.This study reveals a mechanistic switch in the corrosion behavior of Mg alloy(3.6%Al,0.8%Zn)diamond lattice structures,induced by plasma nanosynthesis(400 eV Ar^(+)ions,fluence 1×10^(17) ions/cm^(2)).Plasma treatment of the Mg alloy increases surface Mg from 1.5%to 14.5%,enhances carbonate formation,and generates a nanostructured surface with a Mg carbonate layer over an oxide/hydroxide layer.In vitro and in vivo analyses over 8 wk demonstrate how this treatment fundamentally alters the degradation process and stability of these 3D architectures.While untreated samples initially formed a protective film that subsequently diminished,DPNS-treated samples demonstrated an inverse corrosion behavior.X-ray photoelectron spectroscopy(XPS)and electrochemical impedance spectroscopy(EIS)confirmed the presence of a stable,protective layer composed of magnesium oxide,magnesium hydroxide,and magnesium carbonate on the DPNS-treated surfaces.After 14 days,the DPNS-treated sample exhibited a more positive corrosion potential(-0.69 V versus-1.36 V)and a marginally lower current density(0.73 mA/cm^(2)compared to 0.75 mA/c^(2))relative to the control.This protective layer,combined with modified surface topology,initiated a core-to-periphery degradation pattern that maintained structural integrity for up to 8 wk post-implantation.These findings support the conclusion that the DPNS-treated scaffold demonstrates sustained improved corrosion resistance over time compared to the untreated control.Micro-CT revealed plasma-treated samples retained larger struts(504.9±95.3μm at 8 wk)and formed larger H_(2) pockets extending 14.2 mm from the implant center,versus 4.9 mm in controls.This corrosion behavior switch enhances stability but risks pore clogging,offering insights for tailoring Mg alloy degradation and H_(2) evolution in 3D architectures for biomedical applications. 展开更多
关键词 Mg Corrosion resistance Cellular materials NANOTOPOGRAPHY Nano-medicine Diirected plasma nanosynthesis
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Advances in 18F-fluorodeoxyglucose positron emission tomography/computed tomography for soft tissue sarcomas
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作者 Yan-Lin Zhu Yi-Wen Sun +2 位作者 Yu-Chen Ge Jian He Ru-Tian Li 《World Journal of Radiology》 2025年第7期6-16,共11页
Soft tissue sarcomas(STS)are rare malignant tumors originating from mesoder-mal tissues with a poor prognosis,accounting for approximately 1%of all malig-nancies and comprising around 50 distinct subtypes.Conventional... Soft tissue sarcomas(STS)are rare malignant tumors originating from mesoder-mal tissues with a poor prognosis,accounting for approximately 1%of all malig-nancies and comprising around 50 distinct subtypes.Conventional imaging mo-dalities,such as computed tomography(CT)and magnetic resonance imaging(MRI),primarily provide anatomical information,whereas 18F-fluorodeoxyglucose positron emission tomography/CT(18F-FDG PET/CT)integrates functional metabolic and anatomical imaging,serving as a critical complementary tool in the diagnosis and management of STS.This article reviews recent advances in the application of 18F-FDG PET/CT for STS.The advantages of 18F-FDG PET/CT in STS include:(1)Early detection of metabolic activity changes in tumors,partic-ularly when morphological alterations are insignificant;(2)Effective differen-tiation between benign and malignant soft tissue tumors,as well as aiding in distinguishing high-grade from low-grade sarcomas;(3)Identification of occult metastatic lesions,improving staging accuracy,and facilitating restaging in cases of recurrence or metastasis;(4)Utilization of parameters such as maximum stan-dardized uptake value and metabolic tumor volume to assist in tumor grading and prognostic evaluation;and(5)Monitoring treatment response to guide adjust-ments in personalized therapeutic strategies.However,18F-FDG PET/CT has limitations in diagnosis of certain STS subtypes(e.g.,myxoid liposarcoma),detection and biopsy of metastatic lymph nodes,necessitating integration with clinical evaluation and other imaging techniques.18F-FDG PET/CT is poised to play an increasingly vital role in the precision diagnosis and treatment of STS. 展开更多
关键词 Soft tissue sarcomas Positron radiopharmaceuticals Fluorodeoxyglucose positron emission tomography Positron emission tomography computed tomography
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