内洋地黄素拮抗剂上调缺血再灌注损伤大鼠心肌细胞膜钠泵亚基的表达

目的： 观察内洋地黄素特异性拮抗剂地高辛抗血清对心肌缺血再灌注（MIR）损伤大鼠心肌组织内洋地黄素水平、钠泵活性、线粒体总钙浓度以及钠泵各亚基基因表达的影响，探讨内洋地黄素在心肌缺血再灌注损伤中的作用及其机制。方法: 将56只雄性SD大鼠随机分成7组，每组8只。假手术对照组（sham）：丝线穿过左冠状动脉前降支，但不结扎；缺血再灌注组（MIR）：结扎左冠状动脉前降支30 min，再灌注45 min；生理盐水组（NS）、维拉帕米组（Ver）、小剂量、中剂量、大剂量地高辛抗血清组（ADA）：于再灌注前5 min经股静脉分别注射生理盐水、维拉帕米5 mg·kg^-1、地高辛抗血清8.6 mg·kg^-1、 17.3 mg·kg^-1、34.5 mg·kg^-1，容积均为5 mL·kg^-1，5 min内注射完毕，其余同MIR模型组。再灌注结束后，立即取缺血区左室心肌检测心肌匀浆内洋地黄素水平、心肌细胞膜Na+ K+_ATP酶和Ca2+_Mg2+_ATP酶活性、线粒体总钙浓度；分别采用RT-PCR及Western blotting方法和免疫组化方法检测心肌钠泵α₁、α₂、α₃和β₁亚基mRNA及蛋白水平基因表达的改变。结果: 心肌缺血再灌注损伤时，心肌组织内洋地黄素水平明显升高，心肌细胞膜钠泵和Ca2+_Mg2+_ATP酶活性显著下降，线粒体总钙浓度升高，钠泵α₁、α₂、α₃和β₁亚基在mRNA及蛋白水平基因表达均明显下降；维拉帕米除具有降低线粒体总钙浓度外，对其它各项指标无明显影响。地高辛抗血清呈剂量依赖性地显著降低心肌组织内洋地黄素水平，恢复细胞膜钠泵和Ca2+_Mg2+_ATP酶活性，降低线粒体总钙浓度，上调钠泵α₁、α₂、α₃和β₁亚基mRNA及蛋白水平的基因表达。结论: 心肌缺血再灌注促进机体内洋地黄素分泌增加，后者通过下调心肌细胞膜上的钠泵α₁、α₂、α₃和β₁亚基基因表达抑制钠泵活性，进而抑制Ca2+_Mg2+_ATP酶活性，导致线粒体内钙超载，介导心肌缺血再灌注损伤。内洋地黄素特异性拮抗剂地高辛抗血清通过阻断内洋地黄素的生物学作用，上调钠泵各亚基的基因表达，发挥其抗心肌缺血再灌注损伤的作用。     

氯霉素乙酰基转移酶双抗体夹心ELISA检测方法的建立

目的 建立氯霉素乙酰基转移酶（chloramphenicol acetyltransferase,CAT)双抗体夹心ELISA的实验室检测方法。方法 从质粒pBLCAT6经PCR扩增CAT基因序列，插入到原核表达质粒pGEX-2T中，在大肠埃希菌DH5α中诱导表达；以纯化的融合蛋白GST-CAT为抗原免疫实验用兔，得到的CAT抗血清进行生物素标记，并在此基础上利用生物素链和亲和素放大系统建立双抗体夹心ELISA法，构建不同YY1结合位点突变的HPV16LCRCAT报道质粒，体外瞬时转染真核细胞，提取胞质蛋白，以建立的方法进行CAT表达检测。结果 SDS-PAGE显示表达的GST-CAT融合蛋白相对分子质量约为54000；制备的CAT抗血清可有效地识别原核及哺乳动物细胞表达的CAT蛋白；在不同启动子及调节序列的控制下，利用建立的CAT检测技术证明在瞬时转染的细胞中可诱导2-8倍的CAT表达增强。结论 建立的双抗体夹心ELISA方法可敏感地反映上游序列的启动子活性，以及启动子调节序列变化对启动子活性的影响，使CAT作为报道基因的研究更为简单化。     

一个能诱生戊型肝炎病毒中和抗体的ORF2编码蛋白短片段

目的：比较戊型肝炎病毒（HEV）第4基因型ORF2编码蛋白片段pN472-C617（aa472～617）和pN477-C613（aa477～613）的免疫原性，找到能诱生HEV中和抗体的ORF2编码蛋白的更短片段。方法：表达和纯化pN472-C617和pN477-C613，分别免疫BALB/c小鼠，以间接ELISA检测免疫血清的抗体效价，并以基于PCR的体外中和试验检测免疫血清的中和活性。结果：pN472-C617和pN477-C613可在大肠杆菌高效可溶性表达，纯化后的重组蛋白能在小鼠体内诱导出高效价的抗体。基于PCR的体外中和试验显示pN472-C617免疫血清可有效中和HEV，阻断其在敏感细胞表面的吸附和细胞内复制；而两端仅比pN472-C617各短5个氨基酸的pN477-C613的免疫血清不具有中和HEV的活性。结论：重组蛋白pN472-C617具有良好的抗原性和诱生中和抗体的能力，是目前文献报道中含有HEV中和抗原表位的最短ORF2编码蛋白片段，可作为重组亚单位候选疫苗用于HEV疫苗的开发。     

Production and Characterization of Generic Antibodies Against s-Triazine and Sulfonylurea Herbicides

Two different hapten designs have been suggested for production of generic antibodies. The first approach was based on the immunogen prepared by conjugating simazine mimic to carrier proteins through the Cl position of the s-triazine herbicide. For sulfonylurea herbicides a single ring hapten strategy was designed in order to produce antibodies with dominant selectivity towards arylsulfonyl or triazine moieties of metsulfuron-methyl. The best monoclonal antibody raised against simazine-derived hapten mimic (clone B10/B8/D2) exhibited in direct ELISA a broad pattern for a group of methylthio and methoxy s-triazines. Cross-reactivities based on simazine ( = 100%) were 417, 125, 25, 50, 28, 42 and 11% for simetryn, ametryn, prometryn, terbutryn, aziprotryn, atraton and atrazine, respectively. The superiour generic pattern was found for monoclonal antibody raised against s-triazine moiety of metsulfuron-methyl herbicide (clone 2C8/C8). This antibody showed in indirect ELISA the cross-reactivity values 100, 142, 95, 60, 40, 167, 83 and 21% for metsulfuronmethyl, cinosulfuron, triasulfuron, primisulfuron-methyl, thifensulfuron-methyl, chlorsulfuron and prosulfuron and tribenuron-methyl, respectively. The assays using both monoclonal and polyclonal antibodies operated within the ppt-ppb calibration ranges.     

Detecting antibodies with similar reactivity patterns in the HLDA8 blind panel of flow cytometry data

The blind panel collected for the 8th Human Leucocyte Differentiation Antigens Workshop (HLDA8; ) included 49 antibodies of known CD specificities and 76 antibodies of unknown specificity. We have identified groups of antibodies showing similar patterns of reactivity that need to be investigated by biochemical methods to evaluate whether the antibodies within these groups are reacting with the same molecule. Our approach to data analysis was based on the work of Salganik et al. (in press) [Salganik, M.P., Milford E.L., Hardie D.L., Shaw, S., Wand, M.P., in press. Classifying antibodies using flow cytometry data: class prediction and class discovery. Biometrical Journal].     

新生儿TORCH感染的血清学检测与临床分析

目的 对新生儿进行TORCH感染的血清学检查及临床表现分析。方法 用ELASA法检测血清中TORCH(弓形体、风疹病毒、巨细胞病毒、单纯疱疹病毒)IgM。结果 2000年1月至2003年1月本院新生儿重症监护室(NICU)共收治新生儿l554例，其中48例为TORCH感染，巨细胞病毒感染率最高占52．1％；风疹病毒感染占33．3％；单纯疱疹病毒感染占14．6％。未发现弓形体抗体阳性的患儿。结论 新生儿TORCH感染可造成多器官损伤，主要为听力异常、高胆红素血症和肝功能异常、神经系统损伤、心肌损伤、血小板减少、先天性心脏病。计划免疫、母亲孕期筛查、新生儿早期筛查、干预治疗非常重要。     

A porcine G9 rotavirus strain shares neutralization and VP7 phylogenetic sequence lineage 3 characteristics with contemporary human G9 rotavirus strains

Of five globally important VP7 (G) serotypes (G1-4 and 9) of group A rotaviruses (the single most important etiologic agents of infantile diarrhea worldwide), G9 continues to attract considerable attention because of its unique natural history. Serotype G9 rotavirus was isolated from a child with diarrhea first in the United States in 1983 and subsequently in Japan in 1985. Curiously, soon after their detection, G9 rotaviruses were not detected for about a decade in both countries and then reemerged in both countries in the mid-1990s. Unexpectedly, however, such reemerged G9 strains were distinct genetically and molecularly from those isolated in the 1980s. Thus, the origin of the reemerged G9 viruses remains an enigma. Sequence analysis has demonstrated that the G9 rotavirus VP7 gene belongs to one of at least three phylogenetic lineages: lineage 1 (strains isolated in the 1980s in the United States and Japan), lineage 2 (strains first isolated in 1986 and exclusively in India thus far), and lineage 3 (strains that emerged/reemerged in the mid-1990s). Currently, lineage 3 G9 viruses are the most frequently detected G9 strains globally. We characterized a porcine rotavirus (A2 strain) isolated in the United States that was known to belong to the P[7] genotype but had not been serotyped by neutralization. The A2 strain was found to bear serotype G9 and P9 specificities as well as NSP4 [B] and subgroup I characteristics. By VP7-specific neutralization, the porcine G9 strain was more closely related to lineage 3 viruses than to lineage 1 or 2 viruses. Furthermore, by sequence analysis, the A2 VP7 was shown to belong to lineage 3 G9. These findings raise intriguing questions regarding possible explanations for the emergence of variations among the G9 strains.     

Antigenic sites of coxsackie A9 virus inducing neutralizing monoclonal antibodies protective in mice

A panel of murine IgG monoclonal antibodies (MAbs) was produced against coxsackievirus A9 (CAV9). Fifty-nine MAbs reactive in ELISA with purified CAV9 were identified. Eighteen of them could efficiently inhibit infection by CAV9 but not coxsackieviruses B. Neutralization-resistant CAV9 variants to four different MAbs were isolated and tested for resistance to neutralization by other MAbs of the panel. Three groups of reactivity including 10, 7, and 1 MAbs were thus identified. Sequencing of neutralization-escape virus mutants showed that neutralization by one MAb group was affected by change of VP3 amino acids 62 or 69. For the second group of reactivity, mutations included amino acids 154 or 165 of VP2. The only MAb of the third group selected for a change at residue 70 of VP2. Protection studies in a newborn mouse model of myositis suggested that either epitopes in VP2 or in VP3 mediate protection from CAV9 infection in vivo.     

Preliminary findings in the evaluation of hepatic malignancies by radioimmunodetection,X-ray computed tomography,and magnetic resonance imaging

In 12 consecutive patients with suspected metastatic carcinoma of the liver, we evaluated the sensitivity of radiolabeled antibodies to tumor antigens, magnetic resonance imaging, and X-ray computed tomography imaging in the detection of hepatic malignancies. Studies were performed with ¹³¹I labeled antibodies to CEA and/or CSAp; polyclonal, monoclonal and F(ab)₂ antibodies were used. Nontarget radioactivity was diminished by administration of ^99mTc reagents simulating nontumor distribution and use of a computer substraction method. In nine patients with confirmed liver neoplasms, radioimunodetection disclosed the foci of hepatic malignancies. In three patients with suspected liver neoplasms, the antibody studies were positive, but at this time have not been confirmed. X-ray computed tomography each disclosed mass lesions in five patients and magnetic resonance in three. These findings suggest that radioimmunodetection provides greater accuracy in the detection and localization of cancer than other diagnostic modalities currently used.This research was supported in part by NIH Grants CA37408, CA37409, CA37412, and CA39841     

儿童髓鞘少突胶质细胞糖蛋白抗体相关炎性脱髓鞘疾病临床分析

目的探讨儿童髓鞘少突胶质细胞糖蛋白(MOG)抗体相关炎性脱髓鞘疾病(IDD)患儿的临床表现、影像学特征、治疗方案及临床预后。 方法选择2014年6月1日至2020年9月30日,在中山大学孙逸仙纪念医院儿科确诊的7例MOG抗体相关IDD患儿为研究对象。其中,女性患儿为2例,男性为5例;平均年龄为8.3岁。回顾性分析该7例MOG抗体相关IDD患儿的临床特征、影像学检查结果、治疗方案及临床预后等。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求。 结果①初诊时,这7例患儿分别被误诊为急性播散性脑脊髓炎(ADEM) (2例)、视神经炎(ON)(2例)、多发性硬化症(MS)(1例)、脑膜炎(1例)及自身免疫性脑炎(AE) (1例)。其中年龄较小患儿临床表现为ON症状,而年龄较大者为ADEM症状。②7例患儿中,2例脑脊液检查结果显示白细胞计数(WBC)增高、蛋白水平增高;而脑脊液MOG抗体呈阳性为6例,外周血抗CASPR-2抗体呈阳性为1例;6例患儿颅内压>200 mmH₂O(1 mmH₂O＝0.098 1 kPa)。③7例患儿中,外周血WBC增高为2例,C反应蛋白(CRP)呈阳性为1例、红细胞沉降率(ESR)增高为1例。所有患儿外周血MOG抗体检测结果均呈阳性,而外周血抗CASPR-2抗体呈阳性为1例。④影像学检查结果显示,病变累及侧脑室周围为5例、基底节为3例,丘脑、脊髓和视神经各为2例,脑干和延髓各为1例,伴脑膜强化为1例;而且这7例患儿的病灶直径均>2 cm;年龄>5岁的3例患儿的病灶边界光滑、清晰。⑤治疗方案：1例患儿于急性期静脉输注甲泼尼龙10～30 mg/(kg·d)(每3天剂量递减1/2)+静脉注射免疫球蛋白(IVIG) 2 g/(kg·d)×1 d,6例静脉输注地塞米松[起始剂量为0.5 mg/(kg·d),序贯减量至泼尼松1 mg/(kg·d)口服维持治疗]+IVIG 0.4 g/(kg·d)× 5 d。治疗维持期内,对这7例患儿均进行泼尼松口服治疗,其中5例每个月静脉输注1剂IVIG,剂量为2 g/kg。对2例MOG抗体相关IDD复发患儿,均再次进行静脉输注甲泼尼龙+IVIG治疗,其中1例接受利妥昔单抗治疗的方案为375 mg/(m²·次)×1次/周×4周。治疗后,5例患儿获得完全恢复,2例部分恢复,平均年复发率(ARR)为0.40次/年。 结论MOG抗体相关IDD患儿的临床表现多样,早期易被临床误诊。MOG抗体可与AE相关抗体同时存在,影像学诊断可见多灶性病变。MOG抗体相关IDD虽为MOG抗体所介导,但是MOG抗原的免疫致病性,则与T、B淋巴细胞息息相关。MOG抗体对激素治疗敏感,即使在该病患儿多次复发的情况下,预后亦良好。