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Cross-Reaction between Gliadin and Different Food and Tissue Antigens
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作者 Aristo Vojdani Igal Tarash 《Food and Nutrition Sciences》 2013年第1期20-32,共13页
A subgroup of coeliac disease patients continues to experience symptoms even on a gluten-free diet (GFD). We attempted to determine whether these symptoms could be due to either cross-contamination with gluten-contain... A subgroup of coeliac disease patients continues to experience symptoms even on a gluten-free diet (GFD). We attempted to determine whether these symptoms could be due to either cross-contamination with gluten-containing foods or cross-reactivity between α-gliadin and non-gluten foods consumed on a GFD. We measured the reactivity of affinity-purified polyclonal and monoclonal α-gliadin 33-mer peptide antibodies against gliadin and additional food antigens commonly consumed by patients on a GFD using ELISA and dot-blot. We also examined the immune reactivity of these antibodies with various tissue antigens. We observed significant immune reactivity when these antibodies were applied to cow’s milk, milk chocolate, milk butyrophilin, whey protein, casein, yeast, oats, corn, millet, instant coffee and rice. To investigate whether there was cross-reactivity between α-gliadin antibody and different tissue antigens, we measured the degree to which this antibody bound to these antigens. The most significant binding occurred with asialoganglioside, hepatocyte, glutamic acid decarboxylase 65, adrenal 21-hydroxylase, and various neural antigens. The specificity of anti-α-gliadin binding to different food and tissue antigens was demonstrated by absorption and inhibition studies. We also observed significant cross-reactivity between α-gliadin 33-mer and various food antigens, but some of these reactions were associated with the contamination of non-gluten foods with traces of gluten. The consumption of cross-reactive foods as well as gluten-contaminated foods may be responsible for the continuing symptoms presented by a subgroup of patients with coeliac disease. The lack of response of some CD patients may also be due to antibody cross-reactivity with non-gliadin foods. These should then be treated as gluten-like peptides and should also be excluded from the diet when the GFD seems to fail. 展开更多
关键词 cross-reaction GLIADIN FOOD ANTIGENS Tissue ANTIGENS CELIAC Disease GLUTEN-FREE Diet
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Cross-Reaction of SARS-CoV Antigen with Autoantibodies in Autoimmune Diseases 被引量:7
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作者 YunshanWang ShanhuiSun +8 位作者 HongShen LihuaJiang MaoxiuZhang DongjieXiao YangLiu XiaoliMa YongZhang NongjianGuo TanghongJia 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2004年第4期304-307,共4页
To investigate the significance of the SARS-associated coronavirus (SARS-CoV) antibody,detected by ELISA and indirect immunofluorescence assays (IFA) for the SARS-CoV Vero E6 cell lysates,in non-SARS subjects, 114 ser... To investigate the significance of the SARS-associated coronavirus (SARS-CoV) antibody,detected by ELISA and indirect immunofluorescence assays (IFA) for the SARS-CoV Vero E6 cell lysates,in non-SARS subjects, 114 serum samples from healthy controls and 104 serum specimens from autoimmune disease patients were collected.The results of ELISA showed that among 114 sera from healthy controls,4 (3.5%) were positive of SARS-CoV-IgG antibody and 114 (100%) were all negative of SARS-CoV-IgM antibody;the specificity of SARS-CoV-IgG antibody for SARS patients was 96.5%,but the specificity of both SARS-CoV-IgG and -IgM antibodies for SARS patients was 100%.In 58 cases with SLE,positive rates of SARS-CoV-IgG and -IgM antibodies were 32.8% (19/58) and 8.6% (5/58),respectively,in which 11 cases (19%) were positive of both SARS-CoV-IgG and -IgM antibodies;in 10 cases with SS,positive rate of both SARS-CoV-IgG and -IgM antibodies was 10% (1/10);in 16 cases with MCTD,positive rate of SARS-CoV-IgG was 37.5% (6/16),positive rate of both SARS-CoV-IgG and -IgM antibodies was 6.3% (1/16);in 20 cases with RA,one case was positive (5%) of SARS-CoV-IgG.However,of all samples with positive SARS-CoV-IgG and -IgM antibodies for autoimmune diseases and healthy controls,SARS-CoV RNA and antibodies were all negative by RT-PCR and IFA.All sera for negative or positive ELISA results were also negative or positive results using ELISA with Vero E6 cells lysates.These studies showed that SARS-CoV Vero E6 cell lysates for the ELISA to detect SARS-CoV antibodies could lead to the false-positive reactions or cross-reactions of SARS-CoV antibodies in non-SARS diseases and healthy controls,and the false-positive reactions or cross-reactions were related to Vero E6 cell lysates and autoantibodies in non-SARS population.Cellular & Molecular Immunology.2004;1(4): 304-307. 展开更多
关键词 SARS-COV autoimmune disease cross-reaction
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Occurrence of False-Positive Tests and Cross-reactions Between COVID-19 and Dengue With Implications During Diagnosis:A Mixed Evidence Synthesis
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作者 Daniel C.Digwo Chidinma P.Elebe +3 位作者 Vincent N.Chigor Stella N.Madueke Christian K.Ezeh Anthony C.Ike 《Infectious Microbes & Diseases》 CSCD 2023年第2期64-75,共12页
This review aimed to assess the occurrence of false-positive serological reaction between dengue and coronavirus disease 2019(COVID-19)and its implications for diagnosis.Evidence syntheses were conducted by systematic... This review aimed to assess the occurrence of false-positive serological reaction between dengue and coronavirus disease 2019(COVID-19)and its implications for diagnosis.Evidence syntheses were conducted by systematically reviewing available literature using multiple databases,including Web of Science,PubMed,Google Scholar and medRxiv.Among a total of 16 presented cases from clinical settings,cross-reaction to COVID-19 serological tests was observed in two(12.5%)dengue-positive patients,while 14 patients(87.5%)confirmed positive for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)showed a cross-reaction with dengue serological tests,leading to misdiagnosis and mismanagement by attending clinicians.Of 1789 SARS-CoV-2-positive sera,cross-reaction to dengue serological tests was observed in 180 sera(10%),which is higher than the cross-reaction observed for SARS-CoV-2 in archived pre-COVID-19 sera positive for a dengue infection(75 of 811,9.2%,P=0.674).Clinicians in tropical regions are therefore advised to interpret serological tests with caution and use a more pragmatic approach to triage these infections. 展开更多
关键词 COVID-19 cross-reaction DENGUE SARS-CoV-2
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Cross-reactivity between aeroallergens and food allergens 被引量:12
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作者 Florin-Dan Popescu 《World Journal of Methodology》 2015年第2期31-50,共20页
In patients with respiratory allergy,cross-reactivity between aeroallergens and foods may induce food allergy,symptoms ranging from oral allergy syndrome to severe anaphylaxis.Clinical entities due to Ig E sensitizati... In patients with respiratory allergy,cross-reactivity between aeroallergens and foods may induce food allergy,symptoms ranging from oral allergy syndrome to severe anaphylaxis.Clinical entities due to Ig E sensitization to cross-reactive aeroallergen and food allergen components are described for many sources of plant origin(pollen-food syndromes and associations,such as birch-apple,cypress-peach and celery-mugwortspice syndromes,and mugwort-peach,mugwortchamomile,mugwort-mustard,ragweed-melon-banana,goosefoot-melon associations),fungal origin(Alternariaspinach syndrome),and invertebrate,mammalian or avian origin(mite-shrimp,cat-pork,and bird-egg syndromes).Clinical cases of allergic reactions to ingestion of food products containing pollen grains of specific plants,in patients with respiratory allergy to Asteraceae pollen,especially mugwort and ragweed,are also mentioned,for honey,royal jelly and bee polen dietary supplements,along with allergic reactions to foods contaminated with mites or fungi in patients with respiratory allergy to these aeroallergens.Medical history and diagnosis approach may be guided by the knowledge about the diverse cross-reacting allergens involved,and by the understanding of these clinical entities which may vary significantly or may be overlapping.The association between primary Ig E sensitization with respiratory symptoms to inhaled allergens and food allergy due to cross-reactive allergen components is important to assess in allergy practice.The use of molecular-based diagnosis improves the understanding of clinically relevant Ig E sensitization to cross-reactive allergen components from aeroallergen sources and foods. 展开更多
关键词 cross-reactIVITY SYNDROMES and associations AEROALLERGENS FOOD allergens
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Evaluation of cross-reactive antibody response to HVR1 in chronic hepatitis C
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作者 Bing-Shui Xiu Xiao-Yan Feng +9 位作者 Jing He Guo-Hua Wang He-Qiu Zhang Xiao-Guo Song Kun Chen Shi-Gan Ling Cui-Xia Zhu Xiang-Ying Zhang Lai Wei Hui-Ying Rao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第35期4460-4466,共7页
AIM:To evaluate the presence and cross-reactive anti-bodies against hypervariable region 1(HVR1) in hepatitis C virus(HCV) infected patients and its relationship with the progression of the disease.METHODS:Sixteen rep... AIM:To evaluate the presence and cross-reactive anti-bodies against hypervariable region 1(HVR1) in hepatitis C virus(HCV) infected patients and its relationship with the progression of the disease.METHODS:Sixteen representative HVR1 proteins selected from a unique set of 1600 natural sequences were used to semiquantitate the cross-reactivity of HVR1 antibodies in the sera of HCV patients.Fifty-five chronic HCV patients including 23 with asymptomatic mild hepatitis,18 with chronic hepatitis and 16 with liver cirrhosis patients were studied.RESULTS:The degree of the cross-reactivity of anti-HVR1 antibodies in 23 patients with mild asymptomatic hepatitis was 3.09 ± 2.68,which was signif icantly lower than in those with chronic hepatitis(5.44 ± 3.93,P < 0.05) and liver cirrhosis(7.44 ± 3.90,P < 0.01).No correlation was observed between the broadness of the cross-reactivity anti-HVR1 antibodies and patient's age,infection time,serum alanine aminotransferase activity,or serum HCV-RNA concentration.It was the breath of cross-reactivity rather than the presence of anti-HVR1 antibody in HCV sera that was associated with the progression of liver disease.CONCLUSION:The broadly cross-reactive HVR1 antibodies generated in natural HCV patients can not neutralize the virus,which results in persistent infection in patients with chronic hepatitis. 展开更多
关键词 Hepatitis C virus Hypervariable region 1 cross-reactIVITY
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Studies on Preparation and Characteristics of Monoclonal Antibodies Against Enrofloxacin and Cross-Reactivity of Related Fluoroquinolones
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作者 CAIQin-ren ZENGZhen-ling YANGGui-xiang CHENZhang-liu 《Agricultural Sciences in China》 CAS CSCD 2004年第11期862-868,共7页
An ester activation method was employed to couple enrofloxacin(ENFX) to the carrier proteins BSA and OVA. The conjugates ENFX-BSA and ENFX-OVA were identified with an UV spectrophotometer and amino acid automation a... An ester activation method was employed to couple enrofloxacin(ENFX) to the carrier proteins BSA and OVA. The conjugates ENFX-BSA and ENFX-OVA were identified with an UV spectrophotometer and amino acid automation analysis instrument, and resulted in conjugates with 48 ENFX molecules per carrier molecule(BSA). Splenocytes from mice immunized with ENFX-BSA were fused with SP2/0 myeloma cells and hybridomas secreting antibodies against enrofloxacin were selected and cloned. Two stable monoclonal antibodies, 2C5, 5D5 of the subclass IgG2a, were isolated. Using antibody 5D5, an indirect competitive inhibition enzyme-linked immunosorbent assay (Ci-ELISA) was developed for the quantitative detection of enrofloxacin and its metabolites. The IC50 of the standard curve was 21.67 ng mL-1 and the limit of detection for enrofloxacin was 0.13 ng mL-1. This method was sensitive and had a linear range from 0.13 to 10 000 ng mL-1 (r= -0.9782). Monoclonal antibody 5D5 exhibited high relative affinity to enrofloxacin, and the cross-reactivities with ciprofloxacin, marbofloxacin, sarafloxacin and danorfloxacin were 110.8, 27.40, 71.05 and 37.41%, respectively. Three non-fluoroquinolones of cefadroxil, chloramphenicol, sulfadimethoxine were tested and there was no cross-reaction between them. 展开更多
关键词 ENROFLOXACIN Monoclonal antibodies cross-reactIVITY
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Immunogenicity of Whole Mycobacterium intracellulare Proteins and Fingding on the Cross-Reactive Proteins between M.intracellulare and M.tuberculosis
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作者 XIAO Shi Qi XU Da +12 位作者 DUAN Hong Yang FAN Xue Ting LI Gui Lian ZHANG Wen LI Ma Chao HAN Na LI Xin Yao LI Na ZHAO Li lan ZHAO Xiu Qin WAN Kang Lin LIU Hai Can FENG Wen Hai 《Biomedical and Environmental Sciences》 CSCD 2021年第7期528-539,共12页
Objectives To evaluate the immunogenicity of Mycobacterium intracellulare proteins and determine the cross-reactive proteins between M.intracellulare and M.tuberculosis.Methods Protein extracts from M.intracellulare w... Objectives To evaluate the immunogenicity of Mycobacterium intracellulare proteins and determine the cross-reactive proteins between M.intracellulare and M.tuberculosis.Methods Protein extracts from M.intracellulare were used to immunize BALB/c mice.The antigens were evaluated using cellular and humoral immunoassays.The common genes between M.intracellular and M.tuberculosis were identified using genome-wide comparative analysis,and cross-reactive proteins were screened using immunoproteome microarrays.Results Immunization with M.intracellulare proteins induced significantly higher levels of the cytokines interferon-γ(IFN-γ),interleukin-2(IL-2),interleukin-12(IL-12),interleukin-6(IL-6)and immunoglobulins IgG,IgG1,IgM,and IgG2a in mouse serum.Bone marrow-derived macrophages isolated from mice immunized with M.intracellulare antigens displayed significantly lower bacillary loads than those isolated from mice immunized with adjuvants.Whole-genome sequence analysis revealed 396 common genes between M.intracellulare and M.tuberculosis.Microchip hybridization with M.tuberculosis proteins revealed the presence of 478 proteins in the serum of mice immunized with M.intracellulare protein extracts.Sixty common antigens were found using both microchip and genomic comparative analyses.Conclusion This is the advanced study to investigate the immunogenicity of M.intracellulare proteins and the cross-reactive proteins between M.intracellulare and M.tuberculosis.The results revealed the presence of a number of cross-reactive proteins between M.intracellulare and M.tuberculosis.Therefore,this study provides a new way of identifying immunogenic proteins for use in tuberculosis vaccines against both M.intracellulare and M.tuberculosis in future. 展开更多
关键词 Mycobacterium intracellulare Mycobacterium tuberculosis cross-reactive immune response Vaccine ANTIGEN
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抗H7N9流感病毒的单克隆抗体与胃组织的交叉反应研究
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作者 孙晶莹 张海祥 +4 位作者 冯杨萌 封青 李研 孙丽君 徐翠香 《中国实验诊断学》 2024年第9期1107-1111,共5页
目的筛选鉴定与胃组织交叉反应的抗H7N9流感病毒的单克隆抗体,初步探讨流感病毒感染会引发肠道相关疾病的可能致病机制。方法利用H7N9流感病毒制备了大量的单克隆抗体,对制备的单克隆抗体运用ELISA方法进行亚型和效价测定,免疫组化对制... 目的筛选鉴定与胃组织交叉反应的抗H7N9流感病毒的单克隆抗体,初步探讨流感病毒感染会引发肠道相关疾病的可能致病机制。方法利用H7N9流感病毒制备了大量的单克隆抗体,对制备的单克隆抗体运用ELISA方法进行亚型和效价测定,免疫组化对制备的单克隆抗体与组织的反应性进行筛选,巢式PCR分子生物学技术克隆单克隆抗体轻重链可变区序列。结果制备的单克隆抗体H7N9-71和H7N9-78均能与H7N9抗原特异性结合,抗体效价达1∶10~5,免疫组化结果表明H7N9-71、H7N9-78与人的胃组织能发生特异性反应,进一步的研究发现这两株单抗与小鼠胃组织能特异性结合。轻重链可变区序列结果证实二者为两株不同的单抗。结论H7N9流感病毒可能与胃组织之间存在异嗜性抗原,提示流感病毒感染可能与胃肠道疾病的发生存在某些关联。 展开更多
关键词 H7N9流感病毒 单克隆抗体 交叉反应 抗体可变区
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洛阳市1例华支睾吸虫病误诊误治为弓形虫病的调查报告
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作者 刘英 郭正印 臧珂 《河南医学研究》 CAS 2024年第24期4601-4603,共3页
华支睾吸虫病是由华支睾吸虫感染人和动物引起肝胆病变的一种食源性寄生虫病,多由于人和动物生食或半生食淡水鱼肉引起,在洛阳地区较为少见,临床表现以消化系统病变为主。本文报道了1例33岁男性华支睾吸虫病患者,发病前有食用生鱼片的... 华支睾吸虫病是由华支睾吸虫感染人和动物引起肝胆病变的一种食源性寄生虫病,多由于人和动物生食或半生食淡水鱼肉引起,在洛阳地区较为少见,临床表现以消化系统病变为主。本文报道了1例33岁男性华支睾吸虫病患者,发病前有食用生鱼片的流行病学史,临床症状和体征以腹部不适和肝胆系统损害为主,淋巴结肿大,实验室检查表现为肝功能异常,嗜酸细胞百分比、嗜酸细胞计数升高,C反应蛋白升高。采用肝吸虫抗体检查,但是因和弓形虫病、肺吸虫病存在抗体交叉反应,造成首次住院误诊误治。患者经吡喹酮片治疗后痊愈,出院38 d后复查,各项指标正常。建议对华支睾吸虫病患者采用诊断性治疗,吡喹酮片是治疗华支睾吸虫的特效药。借此病例报道提醒临床医生提高对华支睾吸虫病认识的敏感性,以减少漏诊和误诊。 展开更多
关键词 华支睾吸虫病 临床症状和体征 抗体交叉反应
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基于一个新SiH_(2)(1^(1)A′)势能面的H+SiH反应动力学研究
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作者 赵文丽 宋玉志 +2 位作者 马超 高峰 孟庆田 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第20期195-202,共8页
本文基于2022年报道的一个SiH_(2)(1^(1)A′)势能面,运用切比雪夫波包方法对H(^(2)S)+SiH(X^(2)П;v=0;j=0)→Si(^(1)D)+H_(2)(X^(1)∑_(g)^(+))反应体系在1:0×10^(-3)-1.0 eV的碰撞能量范围内进行动力学研究.分别应用忽略科里奥... 本文基于2022年报道的一个SiH_(2)(1^(1)A′)势能面,运用切比雪夫波包方法对H(^(2)S)+SiH(X^(2)П;v=0;j=0)→Si(^(1)D)+H_(2)(X^(1)∑_(g)^(+))反应体系在1:0×10^(-3)-1.0 eV的碰撞能量范围内进行动力学研究.分别应用忽略科里奥利耦合效应的耦合态近似和精确量子力学计算得到该反应的反应概率、积分散射截面和速率常数.计算发现在J较大时,科里奥利耦合效应显著提升该反应的反应概率,忽略科里奥利耦合效应会使H+SiH反应的积分散射截面和速率常数减小,对于速率常数而言,温度越高,两种计算方法所得结果的差距越大.精确的量子力学计算结果表明,H+SiH反应的速率常数在300-1000 K之间几乎不随温度改变,这与H+CH反应非常相似,但是在数值上,前者比后者大1个数量级. 展开更多
关键词 反应概率 积分散射截面 速率常数
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尘螨-食物过敏综合征 被引量:1
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作者 胡晓甜 蒋萍 《中华临床免疫和变态反应杂志》 CAS 2024年第1期96-100,共5页
尘螨-食物过敏综合征是由于进食与尘螨存在交叉抗原的食物(例如虾等)出现的速发型超敏反应,目前国内外均有报道尘螨与食物之间存在交叉反应,主要交叉抗原为原肌球蛋白。尘螨-食物过敏综合征患者的过敏症状轻重不一,原肌球蛋白致敏对尘... 尘螨-食物过敏综合征是由于进食与尘螨存在交叉抗原的食物(例如虾等)出现的速发型超敏反应,目前国内外均有报道尘螨与食物之间存在交叉反应,主要交叉抗原为原肌球蛋白。尘螨-食物过敏综合征患者的过敏症状轻重不一,原肌球蛋白致敏对尘螨过敏患者在进食虾等食物时应格外注意,以防发生难以预料的过敏事件。 展开更多
关键词 尘螨过敏 食物过敏 交叉反应 支气管哮喘 尘螨-食物过敏综合征
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高压电缆绝缘低密度聚乙烯交联过程中级数和自催化反应的逆向调控 被引量:2
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作者 李加才 尚恺 +2 位作者 司志成 王诗航 李盛涛 《电工技术学报》 EI CSCD 北大核心 2024年第1期13-22,共10页
在保证交联度的前提下提升耐焦烧性能是进一步发展国产高压电缆低密度聚乙烯绝缘料的关键之一。焦烧和交联度本质上是交联反应及其结果的反映,该文基于高分子化学流变学和凝胶理论,提出了绝缘料耐焦烧性能的定量表征方法,结合实验分析... 在保证交联度的前提下提升耐焦烧性能是进一步发展国产高压电缆低密度聚乙烯绝缘料的关键之一。焦烧和交联度本质上是交联反应及其结果的反映,该文基于高分子化学流变学和凝胶理论,提出了绝缘料耐焦烧性能的定量表征方法,结合实验分析和交联反应动力学模型,首次全面探讨了交联反应与焦烧和交联度的关联机理,提出了提升耐焦烧性能并保证交联度的优化策略。研究发现,低密度聚乙烯交联过程中有级数反应和自催化反应,低温下级数反应的级数越低,越有利于延缓交联反应,增加凝胶时间,提高耐焦烧性能;而高温下自催化反应的级数越高,越有利于加速交联反应,提高交联度。单一添加剂只能同向改变级数反应和自催化反应的级数,复合添加剂的协同作用则能逆向改变级数反应和自催化反应的级数,从而实现了在保证交联度的前提下提升绝缘料的耐焦烧性能。该研究为推进高压电缆低密度聚乙烯绝缘料国产化提供了重要理论支撑。 展开更多
关键词 低密度聚乙烯 级数反应 自催化反应 焦烧 交联度
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α-葡萄糖苷酶和人癌细胞的双效抑制剂——天然产物Penasulfate A的优化合成
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作者 张楠 邓昌选 +1 位作者 林汉琳 高阳光 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第12期57-68,共12页
报道了一种天然α-葡萄糖苷酶和人癌细胞的双效抑制剂Penasulfate A的汇聚式合成新方法.以烯烃复分解反应、TEMPO催化氧化、Mitsunobu反应、亚铜盐催化偶联反应和Julia烯烃化反应等为主要反应,通过最长线性10步总收率13.2%完成了Penasul... 报道了一种天然α-葡萄糖苷酶和人癌细胞的双效抑制剂Penasulfate A的汇聚式合成新方法.以烯烃复分解反应、TEMPO催化氧化、Mitsunobu反应、亚铜盐催化偶联反应和Julia烯烃化反应等为主要反应,通过最长线性10步总收率13.2%完成了Penasulfate A的全合成,优于之前合成路线的最长线性14步总收率8.6%.研究结果为Penasulfate A及其类似物的大量合成提供了一个可参考的策略,也为Penasulfate A及其衍生物活性的深入研究创造了条件. 展开更多
关键词 Α-葡萄糖苷酶 抑制剂 偶联反应 烯烃复分解反应
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氮杂环卡宾-铁配合物催化碳-碳偶联反应的研究进展
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作者 代祯 王亚鹏 +7 位作者 赵慧慧 张斌 刘万聪 张静学 何俊 胡嘉涛 刘浩 张翔 《合成化学》 CAS 2024年第5期469-484,共16页
作为传统贵金属催化剂的理想替代品,铁具有来源广泛、毒性低和环境兼容性好等特点,目前被用于多种环境友好的催化过程。近年来,氮杂环卡宾(NHC)由于其独特的空间和电子性质,常作为配体,不仅能够被应用于贵金属(如钯、镍和铑等)催化,在... 作为传统贵金属催化剂的理想替代品,铁具有来源广泛、毒性低和环境兼容性好等特点,目前被用于多种环境友好的催化过程。近年来,氮杂环卡宾(NHC)由于其独特的空间和电子性质,常作为配体,不仅能够被应用于贵金属(如钯、镍和铑等)催化,在铁催化中也得到了广泛的应用。本文综述了氮杂环卡宾及铁配合物催化剂的特点,并重点讨论了近十年其催化的碳-碳偶联包括芳基-芳基交叉偶联、芳基-烷基交叉偶联、烷基-烷基交叉偶联等反应中的研究进展。 展开更多
关键词 氮杂环卡宾配体 铁催化剂 SUZUKI偶联反应 Kumada偶联反应 合成 催化活性
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幽门螺杆菌相关胃外疾病研究进展 被引量:1
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作者 刘晋阳 陈峥宏 +2 位作者 马牧溪 林永帅 谭伟伟 《中国医学科学院学报》 CAS CSCD 北大核心 2024年第3期414-424,共11页
幽门螺杆菌(Hp)是一种常见的胃肠道感染的革兰氏阴性杆菌,主要存在于胃上皮细胞表面和黏液中,与胃溃疡、胃癌和胃黏膜等相关淋巴瘤有关。研究表明Hp可诱发或加重某些胃外疾病,还与新型冠状病毒感染发生有关,因此Hp可能通过刺激机体产生... 幽门螺杆菌(Hp)是一种常见的胃肠道感染的革兰氏阴性杆菌,主要存在于胃上皮细胞表面和黏液中,与胃溃疡、胃癌和胃黏膜等相关淋巴瘤有关。研究表明Hp可诱发或加重某些胃外疾病,还与新型冠状病毒感染发生有关,因此Hp可能通过刺激机体产生炎症因子或发生交叉免疫反应,间接或直接地参与胃外疾病的发生和发展,同时Hp还可进入念珠菌内,持续释放毒素,且发挥躲避免疫系统识别和药物杀菌作用。本文总结近年国内外对Hp相关胃外疾病的研究报道,旨在引起临床工作者对Hp相关胃外疾病的重视,积极地掌握Hp的感染相关学科知识,从而科学制订避免Hp加重或诱发其他疾病的对策。 展开更多
关键词 幽门螺杆菌 胃外疾病 交叉免疫反应 新型冠状病毒感染
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产呕吐毒素蜡样芽孢杆菌聚合酶交联螺旋反应快速检测方法的建立
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作者 王璊 孟祥宇 +1 位作者 程静 庞梦婷 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第7期716-722,共7页
为建立一种快速检测产呕吐毒素蜡样芽孢杆菌(emetic Bacillus cereus)的新型、敏感且可视化的聚合酶交联螺旋反应(PCLSR)方法,本实验根据该菌结构性合成酶基因cesB设计特异性引物,通过对反应体系和反应条件的优化,初步建立了检测emetic ... 为建立一种快速检测产呕吐毒素蜡样芽孢杆菌(emetic Bacillus cereus)的新型、敏感且可视化的聚合酶交联螺旋反应(PCLSR)方法,本实验根据该菌结构性合成酶基因cesB设计特异性引物,通过对反应体系和反应条件的优化,初步建立了检测emetic B.cereus的PCLSR方法。结果显示,PCLSR方法在64℃反应50 min、dNTP浓度为0.3 mol/L、Bst聚合酶浓度为8 U/管时获得最佳扩增效果。以5株emetic B.cereus和12株临床常见菌的DNA作为模板,经本研究建立的该PCLSR方法检测,结果显示,PCLSR法能有效检测5株emetic B.cereus,而对其他相关细菌的检测结果均为阴性,表明该方法特异性较强。将emetic B.cereus 10倍倍比稀释(1×10^(7)cfu/mL~1×10^(0)cfu/mL)后采用该PCLSR法、LAMP法和荧光定量PCR(qPCR)方法检测,结果显示,PCLSR法和qPCR方法的检测限均达1×10^(2)cfu/mL,LAMP法的检测限为1×10^(3)cfu/mL,表明本研究建立的PCLSR法的敏感性较高。采用“国标”中的细菌培养法、PCLSR法、qPCR法及环介导等温扩增(LAMP)法同时检测50份人工污染emetic B.cereus的饲料及灭菌牛奶样品,结果显示,PCLSR法与qPCR法检测emetic B.cereus的阳性率为30%(15/50),阴性率为70%(35/50),二者的符合率均达100%;细菌培养法和LAMP法检测emetic B.cereus的阳性率为24%(12/50),阴性率为76%(38/50),二者与PCLSR法的总符合率均为80%。综上所述,本研究建立的PCLSR法具有较强的特异性、较高的敏感性,且不需要复杂设备和昂贵试剂即可在短时间内完成对emetic B.cereus的检测,该方法的建立为基层部门对emetic B.cereus的检测及该菌的流行病学调查提供了新的技术手段。 展开更多
关键词 蜡样芽孢杆菌 聚合酶交联螺旋反应 检测
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光甘草定的全合成研究
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作者 刘爱云 孙耀华 +1 位作者 王刚 柴永海 《粘接》 CAS 2024年第10期9-12,共4页
光甘草定是光果甘草中一种特有的异黄酮成分,具有广泛的生物活性。以便宜易得的7-羟基香豆素为原料,与2-甲基-3-丁炔-1-氯反应构建酚炔醚,在酚炔醚的α,β-不饱和内酯部分引α-溴原子得到溴代物酚炔醚,该化合物的炔醚部分在加热条件下,... 光甘草定是光果甘草中一种特有的异黄酮成分,具有广泛的生物活性。以便宜易得的7-羟基香豆素为原料,与2-甲基-3-丁炔-1-氯反应构建酚炔醚,在酚炔醚的α,β-不饱和内酯部分引α-溴原子得到溴代物酚炔醚,该化合物的炔醚部分在加热条件下,经分子内环化生成关环产物,关环产物与2,4-二甲氧基苯硼酸经Suzuki偶联,还原共轭双键得双羟基化合物、Mitsunobu成醚、脱除甲基,七步以20%的总收率合成了光甘草定,该方法具有原料便宜易得、总路线短、总收率高等优点。 展开更多
关键词 光甘草定 Szuki偶联反应 全合成
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镍催化的β-溴氨基酸酯的交叉偶联反应的研究
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作者 孙骞 刘银玲 +1 位作者 李鑫雨 唐石 《化工技术与开发》 CAS 2024年第10期19-22,共4页
本文探究了一种β-溴氨基酸酯与烯烃磺酸酯的亲电交叉偶联反应。合成路线以丝氨酸甲酯盐酸盐为原料,先经过胺醛缩合、亲电取代、Appel溴化等一系列反应制得中间产物,再通过亲电交叉偶联反应得到目标产物2-(烯丙基(4-氯苄基)氨基)-3-(4-... 本文探究了一种β-溴氨基酸酯与烯烃磺酸酯的亲电交叉偶联反应。合成路线以丝氨酸甲酯盐酸盐为原料,先经过胺醛缩合、亲电取代、Appel溴化等一系列反应制得中间产物,再通过亲电交叉偶联反应得到目标产物2-(烯丙基(4-氯苄基)氨基)-3-(4-氯苯基)丙酸甲酯。该反应的原料价廉易得,合成路线简洁,产物具有高效性和高区域选择性,实验结果可为氨基酸的修饰提供一条新途径。 展开更多
关键词 氨基酸衍生物 交叉偶联反应 镍催化
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过渡金属催化羰基化反应的最新研究进展
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作者 徐山梅 高帆 +2 位作者 孙国庆 李明 权正军 《西北师范大学学报(自然科学版)》 CAS 2024年第3期5-24,共20页
过渡金属催化羰基化反应是制备羰基化合物最直接的方法之一,近年来得到了迅速的发展.利用活性高且廉价的CO气体作羰基源,通过过渡金属催化的方法实现羰基化,是现代有机合成中构建含羰基化合物的有效方法.基于反应原料和产品氧化还原价... 过渡金属催化羰基化反应是制备羰基化合物最直接的方法之一,近年来得到了迅速的发展.利用活性高且廉价的CO气体作羰基源,通过过渡金属催化的方法实现羰基化,是现代有机合成中构建含羰基化合物的有效方法.基于反应原料和产品氧化还原价态的改变等不同方式,将过渡金属催化羰基化反应分为四种主要类型:杂核亲核试剂的羰基化反应,碳亲核试剂的羰基化反应,碳亲电试剂的羰基化反应和还原偶联的羰基化反应,分别综述了各类型羰基化反应的最新研究进展. 展开更多
关键词 过渡金属催化 一氧化碳(CO) 羰基化反应 交叉偶联 还原偶联
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准均相光催化剂制备及其在交叉脱氢偶联反应中的应用
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作者 王照朋 蔡亭伟 +2 位作者 胡金辉 何瑾馨 赵强强 《应用化工》 CAS CSCD 北大核心 2024年第1期102-107,共6页
以甲基丙烯酸甲酯(MMA)和对氯甲基苯乙烯(VBC)为单体,偶氮二异丁脒盐酸盐(AIBA)为引发剂,通过乳液聚合制备温敏聚合物材料P(MMA-co-VBC x%)。通过接枝反应将玫瑰红(RB)引入到P(MMA-co-VBC x%)中,得到上临界溶解温度(UCST)型准均相聚合... 以甲基丙烯酸甲酯(MMA)和对氯甲基苯乙烯(VBC)为单体,偶氮二异丁脒盐酸盐(AIBA)为引发剂,通过乳液聚合制备温敏聚合物材料P(MMA-co-VBC x%)。通过接枝反应将玫瑰红(RB)引入到P(MMA-co-VBC x%)中,得到上临界溶解温度(UCST)型准均相聚合物催化剂P(MMA-co-VBC x%)-RB y%。使用1H NMR、FTIR和GPC表征了P(MMA-co-VBC x%)和P(MMA-co-VBC x%)-RB y%的结构,分析了温敏材料和准均相催化剂的UCST行为,并以N-芳基四氢异喹啉(THIQ)和硝基甲烷(NM)的交叉脱氢偶联反应(CDC)为模型,研究了准均相催化剂的催化性能和回用性能。结果表明,P(MMA-co-VBC x%)的T cp(浊点)随VBC含量增加而下降,准均相催化剂P(MMA-co-VBC x%)-RB y%的T cp随RB含量增加而下降,在乙醇-水体积比为4∶1时,两类聚合物的响应温度位于40~60℃;P(MMA-co-VBC x%)-RB y%具有较好的溶解-析出性能,溶解-析出循环5次时,回收率>90%;在催化THIQ和NM的反应中,P(MMA-co-VBC x%)-RB y%的催化活性与均相催化剂RB相当,且适用于其他衍生物的反应,降温可回收催化剂,重复使用5次,催化活性无明显下降。 展开更多
关键词 UCST型聚合物 可见光光催化 玫瑰红(RB) 交叉脱氢偶联反应
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