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Structural disruption of melanin-like polymers with boosted UV protection

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Science China Chemistry 2024年第5期67卷 1653-1663页

作者： Zhen Yang Xianheng Wang Wanjie Bai Zikun Zou Haoxing Wu Yiwen Li Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Manipulating the energy structure of materials represents an efficient way to regulate their light absorption behaviors. For example, constructing donor-acceptor(D-A) structures to increase the polarizability and reduce the energy bandgap of local molecules has been widely used in the field of organic photovoltaics with ordered structures. Remarkably, even in disordered and chaotic systems such as melanin-like polydopamine(PDA), visible and near-infrared light absorption can be significantly improved using this strategy. However, there has been a noticeable dearth of research on the ultraviolet(UV) light absorption regulation of bioinspired polymers with disordered and chaotic architectures by tailoring the D-A microstructures. In this study, a series of benzoheterocyclic molecules with strong electron-donating features screened by molecular simulation calculations were involved in disrupting the D-A structures within PDA. The destruction of D-A structures promoted the increase of the energy band gap and finally boosted the UV absorption of PDA. The resulting PDA nanoparticles with enhanced UV absorption were further employed to fabricate UV shielding composite films to protect the growth of plants from harmful UV radiation. This research may open up new avenues for structural disruption of bioinspired polymers for enhanced photoprotection applications.

关键词： melanin-like polymers polydopamine D-A structure UV absorption photoprotection

Synthetic fungal melanin UV absorbers

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Science China Chemistry 2024年第9期67卷 3098-3110页

作者： Chao Wang Rong Zhang Jianhua Zhang Xueqian Zhang Hengjie Zhang Huan Cao Zhen Yang Yiwen Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China

Agents with robust ultraviolet(UV)absorption capabilities play a vital role in safeguarding organisms and inorganic materials from UV ***,the synthetic procedures towards these UV absorbers are usually lengthy and complicated,accompanied by undesirable side reactions and the generation of toxic *** nature,allomelanin,a class of melanins variant found in melanized fungi near the Chernobyl nuclear power plant,plays crucial roles in the cell wall of melanized fungi,offering resistance to harsh external environments and promising UV resistance ***,allomelanin can be rapidly biosynthesized via the polymerization of 1,8-dihydroxynaphthalene in presence of enzymes in *** by this,we report here a green enzymatic polymerization strategy to efficiently and eco-friendly synthesize polydihydroxynaphthalene(PDHN)-based artificial allomelanin nanoparticles(NPs)with interesting *** calculations and experimental results demonstrated that the PDHN NPs exhibited excellent UVabsorption capacity,surpassing another widely used artificial melanin,polydopamine(PDA).Moreover,the light absorption mechanism of PDHN NPs was systematically elucidated for the first ***,the PDHN NPs were incorporated with polyvinyl alcohol(PVA)to create an anti-aging composite film with significantly enhanced UV shielding *** potential of these composite films in safeguarding plants from UV damage was meticulously ***,these PDHN NPs were first found to produce hydroxyl radicals(·OH)under UV irradiation,offering antibacterial properties that expand their potential applications.

关键词： melanin artificial allomelanin nanoparticles green synthesis UV absorption antibacterial

Deep learning model based on PET/CT and combination with Cox proportional hazard model for predicting progression of lung invasive adenocarcinoma after surgery

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中国医学影像技术 2024年第8期40卷 1194-1198页

作者： LI Yingci WU Dongbo GONG Feifei Department of PET/CT-mr.Center Harbin Medical University Cancer HospitalHarbin 150081China Department of Radiology Harbin Medical University Cancer HospitalHarbin 150081China Department of Radiology Harbin Chest HospitalHarbin 150056China

Objective To observe the efficacy of deep learning(DL)model based on PET/CT and its combination with Cox proportional hazard model for predicting progressive disease(PD)of lung invasive adenocarcinoma within 5 years after *** The clinical,PET/CT and 5-year follow-up data of 250 patients with lung invasive adenocarcinoma were retrospectively *** to PD or not,the patients were divided into the PD group(n=71)and non-PD group(n=179).The basic data and PET/CT findings were compared between groups,among which the quantitative variables being significant different between groups were transformed to categorical variables using receiver operating characteristic(ROC)curve and corresponding cut-off *** Cox proportional hazard model was used to select independent predicting factors of PD of lung invasive adenocarcinoma within 5 years after *** patients were divided into training,validation and test sets at the ratio of 6∶2∶2,and PET/CT data in training set and validation set were used to train model and tuning parameters to build the PET/CT DL model,and the combination model was built in serial connection of DL model and the predictive *** test set,the efficacy of each model for predicting PD of lung invasive adenocarcinoma within 5 years after surgery was assessed and compared using the area under the curve(AUC).Results Patients'gender and smoking status,as well as the long diameter,SUV max and SUV mean of lesions measured on PET images,the long diameter,short diameter and type of lesions showed on CT were statistically different between groups(all P4.15(HR=5.249[1.062,25.945],P=0.042)were both predictors of PD of lung invasive adenocarcinoma within 5 years after *** test set,the AUC of PET/CT DL model for predicting PD was 0.847,of the combination model was 0.890,of the latter was higher than of the former(P=0.036).Conclusion DL model based on PET/CT

关键词： adenocarcinoma of lung positron-emission tomography and computed tomography deep learning disease progression

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核磁共振系统用电子监控单元可靠性热设计及其仿真与试验验证

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中国医疗器械杂志 2024年第1期48卷 65-69页

作者：刘庭伟张存礼王亚红董怀宇金月寒通用电气核磁共振mr.京研发中心北京市100176

核磁共振系统用电子监控单元作为系统的重要单机,在全寿命周期内面临着很高的热风险。该文从结构设计、器件降额设计2个维度保证电子模块热设计的高效与可靠。为降低电子模块的热设计风险,全面验证电子模块热设计的有效性,采用仿真与试... 详细信息

核磁共振系统用电子监控单元作为系统的重要单机,在全寿命周期内面临着很高的热风险。该文从结构设计、器件降额设计2个维度保证电子模块热设计的高效与可靠。为降低电子模块的热设计风险,全面验证电子模块热设计的有效性,采用仿真与试验相结合的方法开展设计验证。在仿真环节,通过建立电路板级的热仿真模型,数值计算得到核心器件的结壳温度,并将该指标分别与热设计指标值以及测试值进行比对,一方面验证仿真模型的正确性,另一方面验证热设计的有效性;在测试环节,通过搭建产品模块的热测试平台,获取模块在极限电气工况下,核心器件的热特性测试值,并通过相应的折算方法,预测产品在不同海拔下的热性能与热设计裕度。结果表明,产品模块在结构设计、核心器件降额设计等方面,均能满足热设计要求,可以确保电子模块在核磁共振系统全寿命周期内安全、可靠地工作。

关键词：核磁共振电子模块热设计可靠性设计降额设计热测试有限元仿真

Dendritic nanomedicine enhances chemoimmunotherapy by disturbing metabolism of cancer-associated fibroblasts for deep penetration and activating function of immune cells

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3680-3696页

作者： Yunkun Li Xiaoding Shen Haitao Ding Yuxin Zhang Dayi Pan Liping Su Yahui Wu Zaixiang Fang Jie Zhoua Qiyong Gong Kui Luo Department of Radiology Huaxi MR Research Center(HMRRC)Frontiers Science Center for Disease-Related Molecular NetworkState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China Functional and Molecular Imaging Key Laboratory of Sichuan Province and Research Unit of PsychoradiologyChinese Academy of Medical SciencesChengdu 610041China Department of Radiology West China Xiamen Hospital of Sichuan UniversityXiamen 361021China

Inefficient drug penetration hurdled by the stroma in the tumor tissue leads to a diminished therapeutic effect for drugs and a reduced infiltration level of immune ***,we constructed a PEGylated dendritic epirubicin(Epi)prodrug(Epi-P4D)to regulate the metabolism of cancer-associated fibroblasts(CAFs),thus enhancing Epi penetration into both multicellular tumor spheroids(MTSs)and tumor tissues in mouse colon cancer(CT26),mouse breast cancer(4T1)and human breast cancer(MDA-MB-231)*** cytotoxicity against CT26 MTSs and remarkable antitumor efficacy of Epi-P4D were ascribed to reduced fibronectin,α-SMA,and collagen ***,thinning of the tumor tissue stroma and efficient eradication of tumor cells promoted the immunogenic cell death effect for dendritic cell(DC)maturation and subsequent immune activation,including elevating the CD4^(+)T cell population,reducing CD4^(+)and CD8^(+)T cell hyperactivation and exhaustion,and amplifying the natural killer(NK)cell proportion and effectively activating *** a result,this dendritic nanomedicine thinned the stroma of tumor tissues to enhance drug penetration and facilitate immune cell infiltration for elevated antitumor efficacy.

关键词： Dendritic prodrug Enhanced penetration Metabolic intervention Cancer-associated fibroblasts Immunogenic cell death Chemotherapy Immunotherapy Immune microenvironment reconstitution

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双胞胎先天性弓形虫病一例

放射学实践 2024年第9期 1268-1270页

作者：曾志添赵继泉杨侃荣陈芷茵广东医科大学佛山市第二人民医院mr.

病例资料患儿A,女，30天，双胞胎姐姐，胎龄35周，因胎膜早破剖宫产出生，出生时体重1.44 kg, 羊水清，无窒息抢救史，出生后Apgar评分为10分。于外院行眼底检查发现双眼视网膜病变，遂来我院检查，眼底检查提示“右眼弓形虫病变?左眼... 详细信息

病例资料患儿A,女，30天，双胞胎姐姐，胎龄35周，因胎膜早破剖宫产出生，出生时体重1.44 kg, 羊水清，无窒息抢救史，出生后Apgar评分为10分。于外院行眼底检查发现双眼视网膜病变，遂来我院检查，眼底检查提示“右眼弓形虫病变?左眼早产儿视网膜病变”,查体：头围32 cm, 骨缝增宽，前囟饱满，全身轻度花斑纹，其他无异常。否认发病前14天内曾接触活禽或野生动物。

关键词：弓形虫,先天性双胎妊娠磁共振成像脑积水脉络膜视网膜炎

增强CT灰度共生矩阵预测cN0期甲状腺乳头状癌中央区淋巴结转移

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中国医学影像学杂志 2024年第8期32卷 787-791页

作者：王晨李庆师毅冰徐州市中心医院CT/mr. 江苏徐州221009 徐州市中心医院病理科江苏徐州221009

目的探讨增强CT灰度共生矩阵预测cN0期甲状腺乳头状癌中央区淋巴结转移的价值。资料与方法回顾性分析2020年1月—2021年12月徐州市中心医院经临床、手术病理确诊的cN0期甲状腺乳头状癌患者55例,根据术后病理结果分为中央区淋巴结转移阳... 详细信息

目的探讨增强CT灰度共生矩阵预测cN0期甲状腺乳头状癌中央区淋巴结转移的价值。资料与方法回顾性分析2020年1月—2021年12月徐州市中心医院经临床、手术病理确诊的cN0期甲状腺乳头状癌患者55例,根据术后病理结果分为中央区淋巴结转移阳性组34例、阴性组21例,患者术前均行颈部CT双期增强检查。采用Image J软件分别提取动、静脉期肿瘤最大层面灰度共生矩阵参数(能量、对比、相关、逆差矩、熵)并比较两组各参数的差异,使用受试者工作特征曲线评估参数的预测效能。结果两组间动脉期能量、熵及静脉期熵差异有统计学意义(t/Z=-2.140、2.753、2.736,P0.05)。动脉期能量、动脉期熵、静脉期熵、动脉期能量动脉期熵联合预测中央区淋巴结转移的曲线下面积分别为0.672、0.706、0.686、0.734,动脉期能量动脉期熵联合预测效能最佳,敏感度和特异度分别为76.47%、66.67%。结论增强CT灰度共生矩阵有助于术前预测cN0期甲状腺乳头状癌患者中央区淋巴结转移,动脉期参数能量联合熵的预测效能最佳。

关键词：甲状腺癌,乳头状中央区淋巴结灰度共生矩阵体层摄影术,X线计算机

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联影1.5T磁共振成像序列评估急性踝关节外侧副韧带损伤的初步研究

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中文科技期刊数据库（全文版）医药卫生 2024年第2期 0131-0134页

作者：刘晓涛高碑店市医院CT/mr. 河北保定074000

分析、评价联影1.5T核磁共振成像序列对急性踝关节外侧副韧带损伤的评估与诊断价值。方法纳入在我院就诊的90例疑似急性踝关节外侧副韧带损伤患者,就诊时间在2021.09`2022.09,对所有患者均行联影1.5T核共振成像序列检查与高频超声检查... 详细信息

分析、评价联影1.5T核磁共振成像序列对急性踝关节外侧副韧带损伤的评估与诊断价值。方法纳入在我院就诊的90例疑似急性踝关节外侧副韧带损伤患者,就诊时间在2021.09`2022.09,对所有患者均行联影1.5T核共振成像序列检查与高频超声检查,以关节镜或手术探查诊断结果为准,分析联影1.5T核磁共振成像序列对该类疾病的评估与诊断价值。结果 90例患者经关节镜或手术病理诊断结果:急性踝关节外侧副韧带损伤71例(47.33%),其中ATEL、CFL、PTEL、ATEL合CFL占比率分别为49.29%(35/71)、22.53%(16/71)、9.85%(7/71)、18.30%(13/71);高频超声对ATEL、CFL、PTEL、ATEL合CFL诊断率为43.66%(31/71)、18.30%(13/71)、8.45%(6/71)、16.90%(12/71),总检出率为41.33%(62/150),联影1.5Tmr.成像序列对ATEL、CFL、PTEL、ATEL合CFL诊断率为47.88%(34/71)、21.12%(15/71)、9.85%(7/71)、18.30%(13/71),总检出率为46.00%(69/150);在71例急性踝关节外侧副韧带损伤患者中,联影1.5Tmr.成像序列诊断准确度、特异度、灵敏度分别为92.00%(138/150)、89.87%(71/77)、97.18%(69/71),高频超声诊断准确度、特异度、灵敏度分别为88.00%(129/150)、84.81%(67/79)、87.32%(62/71),前者诊断灵敏度高于后者,Pmr.磁共振成像序列评估、诊断急性踝关节外侧副韧带损伤准确度较高,能够较为准确的诊断出ATEL、CFL、PTEL、ATEL合并CFL类型,可推广应用。

关键词：急性踝关节外侧副韧带损伤联影1.5T磁共振成像高频超声

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飞利浦64排CT对肋骨骨折的诊断研究

中文科技期刊数据库（全文版）医药卫生 2024年第3期 0108-0111页

作者：刘晓涛高碑店市医院CT/mr. 河北保定074000

分析肋骨骨折中CT诊断价值。方法选取300例肋骨骨折患者为对象,所有患者均进行X线和飞利浦64排CT检查,观察结果。结果 64排CT诊断准确率高于X线诊断准确率,具有统计学差异(P<0.05)。结论肋骨骨折影像学诊断中,飞利浦64排CT诊断表现出... 详细信息

分析肋骨骨折中CT诊断价值。方法选取300例肋骨骨折患者为对象,所有患者均进行X线和飞利浦64排CT检查,观察结果。结果 64排CT诊断准确率高于X线诊断准确率,具有统计学差异(P<0.05)。结论肋骨骨折影像学诊断中,飞利浦64排CT诊断表现出更大优势,准确率较高,可清晰观察骨折情况,从而为医生疾病诊断及治疗方案制定提供参考依据。

关键词：飞利浦64排CT 肋骨骨折 X线诊断准确率