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Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic stroke

《医学前沿(英文)》 2022年 第16卷 第3期   页码 429-441 doi: 10.1007/s11684-021-0842-9

摘要: The local microenvironment is essential to stem cell-based therapy for ischemic stroke, and spatiotemporal changes of the microenvironment in the pathological process provide vital clues for understanding the therapeutic mechanisms. However, relevant studies on microenvironmental changes were mainly confined in the acute phase of stroke, and long-term changes remain unclear. This study aimed to investigate the microenvironmental changes in the subacute and chronic phases of ischemic stroke after stem cell transplantation. Herein, induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs) were transplanted into the ischemic brain established by middle cerebral artery occlusion surgery. Positron emission tomography imaging and neurological tests were applied to evaluate the metabolic and neurofunctional alterations of rats transplanted with stem cells. Quantitative proteomics was employed to investigate the protein expression profiles in iPSCs-transplanted brain in the subacute and chronic phases of stroke. Compared with NSCs-transplanted rats, significantly increased glucose metabolism and neurofunctional scores were observed in iPSCs-transplanted rats. Subsequent proteomic data of iPSCs-transplanted rats identified a total of 39 differentially expressed proteins in the subacute and chronic phases, which are involved in various ischemic stroke-related biological processes, including neuronal survival, axonal remodeling, antioxidative stress, and mitochondrial function restoration. Taken together, our study indicated that iPSCs have a positive therapeutic effect in ischemic stroke and emphasized the wide-ranging microenvironmental changes in the subacute and chronic phases.

关键词: ischemic stroke     microenvironment     induced pluripotent stem cells (iPSCs)     positron emission tomography (PET)     quantitative proteomics    

F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma

《医学前沿(英文)》 2021年 第15卷 第6期   页码 913-921 doi: 10.1007/s11684-021-0874-1

摘要: Epileptogenic hypothalamic hamartoma is characterized by intractable gelastic seizures. A systematic analysis of the overall brain metabolic pattern in patients with hypothalamic hamartoma (HH) could facilitate the understanding of the epileptic brain network and the associated brain damage effects of HH. In this study, we retrospectively evaluated 27 patients with epileptogenic HH (8 female patients; age, 2–33 years) by using 18F-fluorodeoxyglucose-positron emission tomography. The correlations among tomography result, seizure type, sex, and structural magnetic resonance imaging were assessed. Whole metabolic patterns and voxel-based morphometry findings were assessed by group analysis with healthy controls. Assessment of the whole metabolic pattern in patients with HH revealed several regional metabolic reductions in the cerebrum and an overall metabolic reduction in the cerebellum. In addition, areas showing hypometabolism in the neocortex were more widely distributed ipsilaterally than contralaterally to the HH. Reductions in glucose metabolism and gray matter volume in the neocortex were predominant ipsilateral to the HH. In conclusion, the glucose hypometabolism pattern in patients with epileptogenic HH involved the neocortex, subcortical regions, and cerebellum. The characteristics of glucose hypometabolism differed across seizure type and sex. Reductions in glucose metabolism and structural changes may be based on different mechanisms, but both are likely to occur ipsilateral to the HH in the neocortex. We hypothesized that the dentato-rubro-thalamic tract and cerebro-ponto-cerebellar tract, which are responsible for intercommunication between the cerebral cortex, subcortical regions, and cerebellar regions, may be involved in a pathway related to seizure propagation, particularly gelastic seizures, in patients with HH.

关键词: hypothalamic hamartoma     gelastic seizure     fluorodeoxyglucose-positron emission tomography     voxel-based morphometry    

用于医学诊断和治疗的质子回旋加速器

樊明武

《中国工程科学》 2000年 第2卷 第12期   页码 9-15

摘要:

在许多医院都安装了生产短寿命放射性同位素的回旋加速器,但用于质子治疗的回旋加速器还处于起步阶段。质子治疗可以达到精确的幅照剂量分布,质子能量决定了穿透深度,因而产生的能量释放点可以精确控制,技术先进。由于质子束传播的线形度好,引起的横向二次散射小,肿瘤前端的健康组织接受的剂量很小,在其周围和之后的组织几乎就没有照射剂量,因此质子束治疗是一种非常有效的方法。束流传输到治疗房间的效率,束流的能量控制、强度及位置的稳定性,快速而精确的改变束流参数来满足临床需要等,都是关键。开发安装于医院的并可满足病人实际需要的质子治疗回旋加速器,包括束流输运系统和一系列的控制系统都相当复杂,文章提出了用于该目的的概念框图和建议。

关键词: 回旋加速器     正电子断层照相     短寿命放射性同位素     质子束治疗    

功能影像检测食管癌放疗过程中再增殖和乏氧以及预测临床疗效研究

于金明

《中国工程科学》 2012年 第14卷 第7期   页码 9-19

摘要:

18F-FLT PET能监测食管鳞癌放疗过程中肿瘤和正常组织的生物学变化,其较18F-FDG PET能较好区分炎症和肿瘤,能检测食管肿瘤放疗过程中的加速再增殖,18F-FETNIM PET能检测食管鳞癌的乏氧状态,18F-FLT PET和18F-FETNIM PET作为一种非创伤性的影像学技术,能为肿瘤医生提供一个早期评价治疗反应,检测放疗过程中的再增殖克隆源细胞、乏氧和评价新辅助治疗疗效的手段。18F-FLT PET和18F-FETNIM PET能为放射治疗确定“再增殖”和“乏氧”生物学靶区,以通过剂量调强放疗提高再增殖和乏氧区域放疗剂量,提高肿瘤的局部控制率和远期生存。

关键词: 食管肿瘤     放射疗法     正电子发射型     再增殖     乏氧    

局部高空间分辨率的应用适应性PET系统设计初探

刘晶晶,谢庆国

《中国工程科学》 2011年 第13卷 第10期   页码 105-112

摘要:

研制成本可负担的高空间分辨率正电子发射断层成像(positron emission tomography,PET)系统在PET成像应用中具有决定性的意义

关键词: 正电子发射断层成像     应用适应性PET系统     感兴趣区域     局部空间分辨率     不同性能探测模块    

PET imaging on neurofunctional changes after optogenetic stimulation in a rat model of panic disorder

Xiao He, Chentao Jin, Mindi Ma, Rui Zhou, Shuang Wu, Haoying Huang, Yuting Li, Qiaozhen Chen, Mingrong Zhang, Hong Zhang, Mei Tian

《医学前沿(英文)》 2019年 第13卷 第5期   页码 602-609 doi: 10.1007/s11684-019-0704-x

摘要: Panic disorder (PD) is an acute paroxysmal anxiety disorder with poorly understood pathophysiology. The dorsal periaqueductal gray (dPAG) is involved in the genesis of PD. However, the downstream neurofunctional changes of the dPAG during panic attacks have yet to be evaluated . In this study, optogenetic stimulation to the dPAG was performed to induce panic-like behaviors, and positron emission tomography (PET) imaging with F-flurodeoxyglucose ( F-FDG) was conducted to evaluate neurofunctional changes before and after the optogenetic stimulation. Compared with the baseline, post-optogenetic stimulation PET imaging demonstrated that the glucose metabolism significantly increased ( <0.001) in dPAG, the cuneiform nucleus, the cerebellar lobule, the cingulate cortex, the alveus of the hippocampus, the primary visual cortex, the septohypothalamic nucleus, and the retrosplenial granular cortex but significantly decreased ( <0.001) in the basal ganglia, the frontal cortex, the forceps minor corpus callosum, the primary somatosensory cortex, the primary motor cortex, the secondary visual cortex, and the dorsal lateral geniculate nucleus. Taken together, these data indicated that PET imaging can successfully detect downstream neurofunctional changes involved in the panic attacks after optogenetic stimulation to the dPAG.

关键词: panic disorder (PD)     positron emission tomography (PET)     optogenetics     dorsal periaqueductal gray (dPAG)    

Philadelphia chromosome-positive acute myeloid leukemia with masses and osteolytic lesions: finding of 18F-FDG PET/CT

null

《医学前沿(英文)》 2017年 第11卷 第3期   页码 440-444 doi: 10.1007/s11684-017-0523-x

摘要:

Philadelphia chromosome-positive acute myeloid leukemia is controversial and difficult to distinguish from the blast phase of chronic myeloid leukemia. As a myeloid neoplasm, rare cases of this leukemia manifest multiple soft-tissue tumors or bone lytic lesions. In this paper, we describe a 49-year-old male patient who had an abrupt onset with sharp chest pain, fever, fatigue, emaciation, and splenomegaly. 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) result showed diffuse and uneven hypermetabolic lesions in the bone marrow with peripheral bone marrow expansion, multiple soft tissue neoplasms with high 18F-FDG uptake, and lytic bone lesions. Bone marrow smear and biopsy detected aberrant blast cells expressing myeloid rather than lymphoid immunophenotype marker. For the existence of Philadelphia chromosome and BCR-ABL1 fusion gene together with complex chromosome abnormalities, a diagnosis of Philadelphia-positive acute myeloid leukemia was made, although the type (de novo or blast crisis) remained unclear.

关键词: Philadelphia chromosome     acute myeloid leukemia     mass     osteolysis     positron emission tomography    

Resveratrol promotes the survival and neuronal differentiation of hypoxia-conditioned neuronal progenitor cells in rats with cerebral ischemia

Yao Yao, Rui Zhou, Rui Bai, Jing Wang, Mengjiao Tu, Jingjing Shi, Xiao He, Jinyun Zhou, Liu Feng, Yuanxue Gao, Fahuan Song, Feng Lan, Xingguo Liu, Mei Tian, Hong Zhang

《医学前沿(英文)》 2021年 第15卷 第3期   页码 472-485 doi: 10.1007/s11684-021-0832-y

摘要: Hypoxia conditioning could increase the survival of transplanted neuronal progenitor cells (NPCs) in rats with cerebral ischemia but could also hinder neuronal differentiation partly by suppressing mitochondrial metabolism. In this work, the mitochondrial metabolism of hypoxia-conditioned NPCs (hcNPCs) was upregulated via the additional administration of resveratrol, an herbal compound, to resolve the limitation of hypoxia conditioning on neuronal differentiation. Resveratrol was first applied during the neuronal differentiation of hcNPCs and concurrently promoted the differentiation, synaptogenesis, and functional development of neurons derived from hcNPCs and restored the mitochondrial metabolism. Furthermore, this herbal compound was used as an adjuvant during hcNPC transplantation in a photothrombotic stroke rat model. Resveratrol promoted neuronal differentiation and increased the long-term survival of transplanted hcNPCs. 18-fluorine fluorodeoxyglucose positron emission tomography and rotarod test showed that resveratrol and hcNPC transplantation synergistically improved the neurological and metabolic recovery of stroke rats. In conclusion, resveratrol promoted the neuronal differentiation and therapeutic efficiency of hcNPCs in stroke rats via restoring mitochondrial metabolism. This work suggested a novel approach to promote the clinical translation of NPC transplantation therapy.

关键词: neuronal progenitor cells     resveratrol     cerebral ischemia     neuronal differentiation     mitochondrial metabolism     positron emission tomography    

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

《结构与土木工程前沿(英文)》 2019年 第13卷 第1期   页码 190-200 doi: 10.1007/s11709-018-0487-1

摘要: Split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC) was examined using two complementary techniques: X-ray computed tomography (CT) and acoustic emission (AE). Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load testing. From the CT images, fiber orientation was evaluated to establish optimum and pessimum specimen orientations, at which fibers would have maximum and minimum effect, respectively. As expected, fiber orientation affected both the peak load and the toughness of the specimen, with the optimum toughness being between 20% and 30% higher than the pessimum. Cumulative AE energy was also affected commensurately. Posttest CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for each. The results showed that fiber pullout was the dominant energy dissipation mechanism; however, the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of load. It is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词: ultra-high-performance concrete     concrete fracture     X-ray computed tomography     acoustic emission    

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

《医学前沿(英文)》 2011年 第5卷 第3期   页码 254-270 doi: 10.1007/s11684-011-0153-7

摘要: Multislice computed tomography (CT) has been widely used in clinical practice for the diagnosis of cardiovascular disease due to its reduced invasiveness and high spatial and temporal resolution. As a reliable alternative to conventional angiography, multislice CT angiography has been recognized as the method of choice for detecting and diagnosing head and neck vascular disease, abdominal aortic aneurysm, aortic dissection, and pulmonary embolism. In patients with suspected coronary artery disease, although invasive coronary angiography still remains as the gold standard technique, multislice CT angiography demonstrates high diagnostic accuracy; in selected patients, it is considered as the first-line technique. The imaging diagnosis of cardiovascular disease is based on a combination of two-dimensional (2D) and three-dimensional (3D) visualization tools to enhance the diagnostic value. This is facilitated by reconstructed visualizations which provide additional information about the extent of the disease, an accurate assessment of the spatial relationship between normal structures and pathological changes, and pre-operative planning and post-procedure follow-up. The aim of the present article is to present an overview of the diagnostic performance of various 2D and 3D CT visualizations in cardiovascular disease, including multiplanar reformation, maximum intensity projection, volume rendering, and virtual intravascular endoscopy. The recognition of the potential value of these visualizations will assist clinicians in efficiently using the multislice CT imaging modality for the diagnostic management of patients with cardiovascular disease.

关键词: cardiovascular disease     multislice computed tomography     three-dimensional reconstruction     diagnosis     visualization    

of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitance tomography

CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan

《机械工程前沿(英文)》 2006年 第1卷 第2期   页码 242-247 doi: 10.1007/s11465-006-0008-0

摘要: Sensor sensitivity field in electrical capacitance tomography is affected by the distribution of multiphase medium, which is the peculiarity of soft field. This brings great difficulty for image reconstruction. To improve the quality of image reconstruction, it is important to analyze the distribution of the sensitivity field. In this article, using the finite element method, we expound a kind of novel plotting pattern to field, which is the distribution of sensitivity field through computer simulation. From experiments and results of sensitivity field analysis, a novel method of image reconstruction based on genetic algorithms is presented. The finite element model is correct and simulation result is fine by adopting unequal interval plotting patterns. At the same time, the result of image reconstruction has high precision.

关键词: multiphase     unequal interval     capacitance tomography     pattern     sensitivity    

珊瑚岛礁环境噪声成像 Article

夏少红, 张昌榕, 曹敬贺

《工程(英文)》 2023年 第25卷 第6期   页码 182-193 doi: 10.1016/j.eng.2021.09.022

摘要:

As valuable land in the ocean, coral islands are not only important bases for making use of marine resources and protecting marine rights and interests, but also important for breakthrough research in many fields of earth science. Hence, the economical and efficient determination of the underground structure of coral islands has become significant in coral island engineering geology, but remains challenging for traditional marine geophysical prospecting and drilling methods. While ambient noise tomography with dense arrays has been widely used in continental regions, its applicability to coral islands remains undetermined. In this study, based on the data recorded by a dense array on an isolated coral island in the South China Sea, we analyzed the ambient noise characteristics and obtained a 3D subsurface structure of the coral island using ambient noise tomography. We made the following findings: ① The ambient noise frequencies can be roughly categorized into three levels: < 1, 1–5, and > 5 Hz. The spectral characteristics of the noise below 5 Hz were consistent at different stations, but there were significant differences in the characteristics of the noise above 5 Hz. ② For ambient noise frequencies below 5 Hz, cross-correlation functions with high quality could be obtained with only 24 h of waveform data. However, it was difficult to extract meaningful cross-correlation functions for ambient noise frequencies above 5 Hz. ③ The S-wave velocity in the coral island was higher toward the sea and lower toward the lagoon, which was consistent with the high degree of cementation of the outer reef flat stratum on the seaward side. ④ There were two low-velocity horizons at 25–75 and 200–300 m, which were in good agreement with the high-porosity horizons that were revealed by drilling core samples, reflecting the weathering history of the reef. Our research demonstrates that ambient noise tomography is a potentially economical, efficient, and environmentally friendly method for the geological prospecting of coral reefs.

关键词: Coral island     Ambient noise tomography     Engineering geology     South China Sea    

A new prediction method of industrial atmospheric pollutant emission intensity based on pollutant emission

《环境科学与工程前沿(英文)》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1608-1

摘要:

● Established a quantification method of pollutant emission standard.

关键词: Industrial atmospheric pollutants     Pollutant emission standards     Quantitative method     Machine learning     Single enterprise    

properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography

Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA

《结构与土木工程前沿(英文)》 2019年 第13卷 第3期   页码 640-652 doi: 10.1007/s11709-018-0502-6

摘要: A significant volume of Municipal Solid Waste incineration bottom ash and fly ash (i.e., incineration residues) are commonly disposed as landfill. Meanwhile, reclamation of landfill sites to create a new land space after their closure becomes an important goal in the current fewer and fewer land availability scenario in many narrow countries. The objective of this study is to reclaim incineration residue materials in the landfill site by using cement and coal fly ash as stabilizers aiming at performing quality check as new developed materials before future construction. Indeed, physical and mechanical properties of these new materials should be initially examined at the micro scale, which is the primary fundamental for construction at larger scale. This research examines quantitative influences of using the combination of cement and coal fly ash at different ratio on the internal structure and ability of strength enhancement of incineration residues when suffering from loading. Couple of industrial and micro-focus X-ray computed tomography (CT) scanners combined with an image analysis technique were utilized to characterize and visualize the behavior and internal structure of the incineration residues-cement-coal fly ash mixture under the series of unconfined compression test and curing period effect. Nine types of cement solidified incineration residues in term of different curing period (i.e., 7, 14, 28 days) and coal fly ash addition content (i.e., 0%, 9%, 18%) were scanned before and after unconfined compression tests. It was shown that incineration residues solidified by cement and coal fly ash showed an increase in compression strength and deformation modulus with curing time and coal fly ash content. Three-dimension computed tomography images observation and analysis confirmed that solidified incineration residues including incineration bottom and fly ash as well as cement and coal fly ash have the deliquescent materials. Then, it was studied that stabilized parts play a more important role than spatial void distribution in increment or reduction of compression strength.

关键词: mechanical property     municipal solid waste incineration residues     coal fly ash     unconfined compression test     image analysis     X-Ray Computed Tomography scanners    

Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic helical scan on 16 MDCT

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

《医学前沿(英文)》 2009年 第3卷 第2期   页码 230-235 doi: 10.1007/s11684-009-0023-8

摘要: We implemented a new protocol — multiphase dynamic helical scan to acquire CT angiography (CTA) and whole brain CT perfusion (CTP) images simultaneously with single scan on 16 multidetector CT (MDCT). A total of 90 patients who were randomly assigned into 3 groups were included in our study. Each group underwent CT scan by using the new protocol, traditional CTA and CTP protocol, respectively. The image quality of CTA, the CTP parameter values and the X-ray doses were measured and compared between the new protocol and the traditional protocols. There was no statistically significant difference in the CTA image quality between the above methods ( =0.55). For CTP parameters, the new protocol tended to overestimate the blood volume (BV) and blood flow (BF) value, and to underestimate the mean transit time (MTT) value compared with the traditional method. However, there was no statistically significant difference in BV, BF, and MTT value between the two methods except permeability surface (PS) ( >0.05). The volume CT dose index (CTDIvol) and dose length product (DLP) of our protocol were lower than the traditional one. The new protocol can obtain valuable diagnostic information in a shorter time without significant compromise in image quality. In addition, it reduces the radiation dose as well as contrast medium usage on the patient.

关键词: computed tomography angiography     computed tomography perfusion    

标题 作者 时间 类型 操作

Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic stroke

期刊论文

F-FDG-PET glucose hypometabolism pattern in patients with epileptogenic hypothalamic hamartoma

期刊论文

用于医学诊断和治疗的质子回旋加速器

樊明武

期刊论文

功能影像检测食管癌放疗过程中再增殖和乏氧以及预测临床疗效研究

于金明

期刊论文

局部高空间分辨率的应用适应性PET系统设计初探

刘晶晶,谢庆国

期刊论文

PET imaging on neurofunctional changes after optogenetic stimulation in a rat model of panic disorder

Xiao He, Chentao Jin, Mindi Ma, Rui Zhou, Shuang Wu, Haoying Huang, Yuting Li, Qiaozhen Chen, Mingrong Zhang, Hong Zhang, Mei Tian

期刊论文

Philadelphia chromosome-positive acute myeloid leukemia with masses and osteolytic lesions: finding of 18F-FDG PET/CT

null

期刊论文

Resveratrol promotes the survival and neuronal differentiation of hypoxia-conditioned neuronal progenitor cells in rats with cerebral ischemia

Yao Yao, Rui Zhou, Rui Bai, Jing Wang, Mengjiao Tu, Jingjing Shi, Xiao He, Jinyun Zhou, Liu Feng, Yuanxue Gao, Fahuan Song, Feng Lan, Xingguo Liu, Mei Tian, Hong Zhang

期刊论文

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

Eric N. LANDIS, Roman KRAVCHUK, Dmitry LOSHKOV

期刊论文

Multislice computed tomography angiography in the diagnosis of cardiovascular disease: 3D visualizations

Zhonghua Sun

期刊论文

of plotting sensor sensitivity field and image reconstruction algorithm for electrical capacitance tomography

CHEN De-yun, YANG Cong-jing, ZHENG Gui-bin, YU Xiao-yang, SUN Li-juan

期刊论文

珊瑚岛礁环境噪声成像

夏少红, 张昌榕, 曹敬贺

期刊论文

A new prediction method of industrial atmospheric pollutant emission intensity based on pollutant emission

期刊论文

properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography

Toshifumi MUKUNOKI, Ta Thi HOAI, Daisuke FUKUSHIMA, Teppei KOMIYA, Takayuki SHIMAOKA

期刊论文

Simultaneous acquisition of CT angiography and whole brain CT perfusion images by using multiphase dynamic helical scan on 16 MDCT

Weiwei CHEN, Jianpin QI, Wenzhen ZHU, Wenhua HUANG, Jinmei SONG

期刊论文