脑膜炎球菌荚膜多糖氧乙酰基相关特性及其作用机理

氧乙酰基(O-acetyl,OAc)存在于许多细菌多糖中,如脑膜炎球菌(meningococcus)A、C、W135、Y群荚膜多糖、大肠杆菌K1型荚膜多糖等均存在氧乙酰化修饰。由于荚膜多糖(capsular polysaccharides, CPS)中OAc的分布和占比被视为脑膜炎球菌多糖候选疫苗的关键质量控制因素,氧乙酰化修饰对多糖疫苗的免疫原性的重要作用,特别是脑膜炎球菌CPS OAc对其疫苗免疫原性的影响越来越受到关注。现就脑膜炎球菌CPS OAc的相关特性和检测方法、迁移因素、OAc修饰及其作用、OAc转移酶的作用机制、OAc对脑膜炎球菌免疫原性的影响作一概述,有助于脑膜炎球菌荚膜多糖疫苗安全性和免疫原性的评价。     

乙醇、丙酮和氯化钙对W135群脑膜炎球菌荚膜多糖唾液酸含量检测的影响

目的研究乙醇、丙酮和氯化钙是否影响间苯二酚法测定W135群脑膜炎球菌荚膜多糖(group W135 meningococcal capsular polysaccharide)唾液酸(sialic acid)含量。方法用苯酚法制备W135群脑膜炎球菌荚膜多糖;分别定量检测唾液酸和W135群脑膜炎球菌荚膜多糖添加不同质量浓度乙醇、丙酮和氯化钙,用间苯二酚法测定其唾液酸含量,检测乙醇、丙酮和氯化钙对间苯二酚测定唾液酸含量的影响。结果添加质量浓度≥39.5μg/mL的乙醇和≥9.9μg/mL的丙酮对唾液酸含量测定均有影响,其中乙醇影响不明显,丙酮的影响极为明显,而不同加入量的氯化钙均对唾液酸含量的测定无影响。结论乙醇和丙酮对间苯二酚法测定唾液酸含量有影响,二者可能会对W135群脑膜炎球菌荚膜多糖质量控制产生影响。     

2～59岁健康人群接种ACYW135群脑膜炎球菌多糖疫苗的免疫原性观察

目的评价ACYW135群脑膜炎球菌多糖疫苗在2～59岁健康人群中的免疫原性。方法 2～59岁健康人群接种者随机抽样(n=60),接种一剂四价脑膜炎球菌多糖疫苗。采集接种前和接种后1个月血清,采用体外杀菌试验(Serum bactericidal assay,SBA)检测血清中抗A、C、Y、W135群脑膜炎球菌的血清杀菌滴度。结果免疫前、后血清抗A群脑膜炎球菌的血清杀菌滴度GMTs(95%CI)分别为1241(736,2091)和7559(5520,10351)(P<0.05);抗C群脑膜炎球菌的血清杀菌滴度GMTs(95%CI)分别为4(9,21)和4787(2947,7775)(P<0.05);抗W135群脑膜炎球菌的血清杀菌滴度GMTs(95%CI)分别为16(9,28)和368(162,883)(P<0.05);抗Y群脑膜炎球菌的血清杀菌滴度GMTs(95%CI)分别为120(58,246)和1373(687,2745)(P<0.05)。免疫前和免疫后血清抗A群脑膜炎球菌的杀菌滴度≥128的比例分别为87(77.4,95.1)%和100(83.2,100)%;抗C群脑膜炎球菌的比例分别为17(8.3,28.5)%和97(88.5,99.6)%;抗W135群脑膜炎球菌的比例分别为13(5.9,24.6)%和68(55.0,79.7)%;抗Y群脑膜炎球菌的比例分别为57(43.2,69.4)%和85(73.4,92.9)%。免疫后较免疫前抗A群、C群、W135群和Y群脑膜炎球菌杀菌抗体滴度≥4倍升高的比例分别为50(27.2,72.8)%、97(88.5,99.6)%、62(43.2,73.9)%和55(41.6,67.9)%。结论虽然免疫前人群由于地方和国家免疫计划的实施已具有较高水平的抗A群脑膜炎球菌的血清杀菌滴度,但接种ACYW135群脑膜炎球菌多糖疫苗后可以使其保护水平进一步提高,并使人群对C群、W135群和Y群脑膜炎球菌的低水平杀菌抗体滴度均显著升高达到保护水平,证明ACYW135群脑膜炎球菌多糖疫苗在2～59岁健康人群中具有比较好的免疫原性。     

不同酸水解酪蛋白对W135群和Y群脑膜炎奈瑟菌荚膜多糖产量的影响

目的 探索不同酸水解酪蛋白对W135群与Y群脑膜炎奈瑟菌(脑膜炎球菌)荚膜多糖产量的影响。方法 分别以NaCl质量分数为37%和14%的酸水解酪蛋白作为有机氮源配制改良半综合高盐培养基和低盐培养基,利用全自动细菌发酵罐分别在两种培养基里培养W135群和Y群脑膜炎球菌,比较这两种菌株在两种培养基中的生长时间、收获液菌密度( A 600 nm 值)、收获液去菌体后与去复合多糖后上清中的荚膜多糖含量,以及纯化后的精糖产量;比较高盐培养基收获液及其2倍稀释液中不同终含量的十六烷基三甲基溴化铵(cetyltrimethylammonium bromide, CTAB)溶液对多糖沉淀效果的影响。结果 W135群与Y群脑膜炎球菌在两种培养基中的培养时间差异无统计学意义( P >0.05),但高盐培养基收获液的菌密度、收获液去菌体后上清液中的多糖含量均高于低盐培养基收获液,差异有统计学意义( P < 0.05),而高盐培养基收获液纯化后的精糖产量低于低盐培养基,差异有统计学意义( P <0.05)。高盐培养液2倍稀释后,在CTAB终体积分数为0.04%时,W135群与Y群脑膜炎球菌多糖全部沉淀,而未稀释高盐培养液即使CTAB终体积分数提高到0.14%,依然也不能完全沉淀 W135群与Y群脑膜炎球菌多糖。结论 不同酸水解酪蛋白对W135群和Y群脑膜炎球菌的生长密度和荚膜多糖产量有影响,用CTAB溶液沉淀荚膜多糖时需控制收获液盐含量。     

ACYW135群脑膜炎球菌多糖疫苗的免疫原性评价

目的评价ACYW135群脑膜炎球菌多糖疫苗在昆明健康人群接种的免疫原性,为流脑防治策略提供依据。方法 2010年对昆明市2岁!3、岁!、4岁!、5岁!、6岁!、10岁!、≥15岁共7个年龄组分层随机抽取筛选出654名健康人,分别采集免前和免后1个月血清。用微量杀菌力试验(TTC法)分别检测血清中抗A、C、Y和W135群脑膜炎球菌杀菌抗体的水平。结果免后1个月抗A、C、Y和W135群脑膜炎球菌的杀菌抗体阳转率分别为96.99%、96.37%、88.43%和87.07%,抗A、C、Y和W135群膜炎球菌血清的杀菌抗体几何平均滴度(GMT)分别为1∶297.991、∶195.80、1∶72.74和1∶45.95。结论 ACYW135群脑膜炎球菌多糖疫苗在≥2岁以上的健康人群中有较好的免疫原性。     

不同的甲醛杀菌浓度对A群、C群脑膜炎球菌荚膜多糖内毒素含量的影响

目的研究不同的甲醛杀菌浓度对A群、C群脑膜炎球菌荚膜多糖内毒素含量的影响。方法将A群脑膜炎球菌发酵液分成A、B两组,A组采用体积分数为2.5%甲醛杀菌,B组采用体积分数为2.0%甲醛杀菌。将C群脑膜炎球菌发酵液分成C、D两组,C组采用体积分数为2.5%甲醛杀菌,D组采用体积分数为2.0%甲醛杀菌。分别纯化获得荚膜多糖,用动态浊度法测定荚膜多糖中内毒素的含量。结果 A、C两组荚膜多糖中内毒素含量显著低于B、D两组荚膜多糖中的内毒素含量(P<0.05)。结论使用不同浓度的甲醛杀菌,对A群、C群脑膜炎球菌荚膜多糖内毒素的含量有显著影响。较高浓度的甲醛利于菌体细胞的固定,从而防止细菌自溶释放内毒素,因而高浓度的甲醛能够减少其内毒素的含量,提高了产品质量。     

高效阴离子交换色谱-脉冲安培法检测A、C、Y和W135群脑膜炎球菌多糖含量

目的用高效阴离子交换色谱-脉冲安培检测法(HPAEC-PAD)测定A、C、Y和W135群脑膜炎球菌多糖含量,并对该方法进行验证及初步应用。方法采用Carbo Pac~?PA-1 4×250 mm分析柱与Aminotrap 4×50 mm保护柱;使用氢氧化钠/醋酸钠梯度洗脱,以多糖抗原标准溶液质量浓度为横坐标,其相应的峰面积为纵坐标,绘制标准曲线,并对建立的方法进行专属性、精密度和准确性验证;同时与传统方法的检测结果进行比较分析。结果 A、C、Y和W135群脑膜炎球菌多糖质量浓度在0.5～27.0μg/m L范围内与峰面积均具有良好线性关系,r=0.999。该方法专属性高,分析结果重复性良好,RSD均5%;回收率均在95%～105%范围内;与传统的火箭免疫电泳法相比,检测结果差异均无统计学意义(P0.05)。结论 HPAEC-PAD准确、可靠,重复性好,可用于检测脑膜炎球菌多糖原液及疫苗成品中的多糖含量。     

新型脑膜炎奈瑟球菌X群荚膜多糖单克隆抗体及其潜在应用

正针对脑膜炎奈瑟球菌X群荚膜多糖(Men X)研制的一种新型鼠杂交瘤细胞单克隆抗体(MAb)可用于酶联免疫法对脑膜炎球菌多糖进行定量。该单克隆抗体只对X群发生反应,对于脑膜炎奈瑟菌A群C群Y群和W群均不反应。由非竞争性ELISA测定的单克隆抗体的亲和常数值(Ka)为7.25×     

HPLC法测定A群C群脑膜炎球菌多糖疫苗中乳糖含量

建立了高效液相色谱法测定A群C群脑膜炎球菌多糖疫苗中乳糖的含量。样品经离心除去多糖后,采用阳离子交换柱分离,外标法定量分析。该法线性相关系数大于0.9999,回收率为98.8%,成品测定的CV值为1.2%(<2%),该法定量准确,重复性好,适于对A群C群脑膜炎球菌多糖疫苗中乳糖含量进行快速检测。     

速率比浊法检测ACYW135群脑膜炎球菌结合疫苗中各群多糖含量

目的建立速率比浊法准确检测ACYW135群脑膜炎球菌结合疫苗(group ACYW135 meningococcal conjugate vaccine)的各群多糖含量。方法制备多糖参考品和抗血清,建立检测ACYW135群脑膜炎球菌结合疫苗各群多糖含量的速率比浊法,对建立的方法进行验证及初步应用。结果①建立的方法具备高度的特异性,各群血清仅与本群多糖抗原发生特异性反应,与非本群多糖抗原无交叉反应;②在质量浓度为0.5～5.0μg/mL多糖参考品检测区间线性良好,相关系数r>0.98;③各群血清的最低检测限均低于质量浓度为0.35μg/mL;④批内和批间变异系数(CV)值分别为0.83%～5.34%和2.33%～13.88%,加样回收率为90.5%～118.4%,精密度和准确度均符合常规质量控制要求;⑤初步应用结果显示,建立的方法可准确检测疫苗的各群多糖含量,且与火箭电泳法检测结果差异无统计学意义(P>0.05)。结论建立的方法简便快捷、灵敏准确、自动化程度高,可有效检测ACYW135群脑膜炎球菌结合疫苗的各群多糖含量。     

Definitions,measurements, and classifications of stimuli,situations, and environments

A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.     

Synthesis,tautomerism, and antimicrobial,anti-HCV,anti-SSPE,antioxidant, and antitumor activities of arylazobenzosuberones

2-Dimethylaminomethylene-1-benzosuberone 1 was coupled with diazotized aniline derivatives to afford a series of the hitherto unreported 2-arylazo-1-benzosuberones 3a–i. The tautomeric structure and the effect of substituents on the tautomeric form (s) of the products 3a–i were discussed. Similar coupling of the enaminone 1 with diazonium salts of heterocyclic amines gave the respective fused azolotriazino-benzosuberones. Some of the newly synthesized compounds showed potent antimicrobial, anti-HCV, antioxidant, antitumor (as topoisomerase I inhibitors), and antimicrobial activities.     

Low-frequency dynamics and Raman scattering of crystals, of B-, A-, and Z-DNA, and fibers of C-DNA

Normal modes of vibration of DNA in the low-frequency region (10-300 cm-1 interval) have been identified from Raman spectra of crystals of B-DNA [d(CGCAAATTTGCG)], A-DNA [r(GCG)d(CGC) and d(CCCCGGGG)], and Z-DNA [d(CGCGCG) and d(CGCGTG)]. The lowest vibrational frequencies detected in the canonical DNA structures--at 18 +/- 2 cm-1 in the B-DNA crystal, near 24 +/- 2 cm-1 in A-DNA crystals, and near 30 +/- 2 cm-1 in Z-DNA crystals--are shown to correlate well with the degree of DNA hydration in the crystal structures, as well as with the level of hydration in calf thymus DNA fibers. These findings support the assignment [H. Urabe et al. (1985) J. Chem. Phys. 82, 531-535; C. Demarco et al. (1985) Biopolymers 24, 2035-2040] of the lowest frequency Raman band of each DNA to a helix mode, which is dependent primarily upon the degree of helix hydration, rather than upon the intrahelical conformation. The present results show also that B-, A-, C-, and Z-DNA structures can be distinguished from one another on the basis of their characteristic Raman intensity profiles in the region of 40-140 cm-1, even though all structures display two rather similar and complex bands centered within the intervals of 66-72 and 90-120 cm-1. The similarity of Raman frequencies for B-, A-, C-, and Z-DNA suggests that these modes originate from concerted motions of the bases (librations), which are not strongly dependent upon helix backbone geometry or handedness. Correlation of the Raman frequencies and intensities with the DNA base compositions suggests that the complex band near 90-120 cm-1 in all double-helix structures is due to in-plane librational motions of the bases, which involve stretching of the purine-pyrimidine hydrogen bonds. This would explain the centering of the band at higher frequencies in structures containing G.C pairs (greater than 100 cm-1) than in structures containing A.T pairs (less than 100 cm-1), consistent with the strengths of G.C and A.T hydrogen bonding.     

Synthesis and properties of N-, O-, and S-phospho derivatives of amino acids, peptides, and proteins

The literature on chemical (i.e., nonenzymic) phosphorylation of amino acids, peptides, and proteins is reviewed through 1982. The review covers synthetic methods, chemical reactions, and physical properties, with emphasis on the techniques used for separation and characterization of the products. Synthetic methods are classified by reagent rather than product, and are illustrated by experimental procedures for the most important methods. Chemical reactions are classified into four groups depending on whether the reaction site is the phospho group, the amino group, the carboxyl group, or in the case of serine the hydroxyl group. Physical data are given for all of the known N-, O-, and S-phospho derivatives of the amino acids, peptides, and proteins, within certain limitations, and are discussed in detail in the section on physical properties. Emphasis is given to the techniques used for separation of the products, such as chromatography and electrophoresis, and for characterization of the products, particularly spectroscopy. Medical and other uses of the products are mentioned.     

Cultural, Biochemical, and Immunological Properties of Mima, Herellea, and Flavobacterium Species

From study of cultural and biochemical characteristics of 40 strains of Herellea, Mima, or Flavobacterium species, a proposed schema for identification was developed. The reactions observed by agglutination, gel diffusion, and immunofluorescence suggest antigenic heterogeneity of this group of organisms.     

Count data, detection probabilities, and the demography, dynamics, distribution, and decline of amphibians

The evidence for amphibian population declines is based on count data that were not adjusted for detection probabilities. Such data are not reliable even when collected using standard methods. The formula C = Np (where C is a count, N the true parameter value, and p is a detection probability) relates count data to demography, population size, or distributions. With unadjusted count data, one assumes a linear relationship between C and N and that p is constant. These assumptions are unlikely to be met in studies of amphibian populations. Amphibian population data should be based on methods that account for detection probabilities.