Oral vaccination of brushtail possums with BCG: Investigation into factors that may influence vaccine efficacy and determination of duration of protection

AIMS: To determine factors that may influence the efficacy of an oral pelleted vaccine containing Mycobacterium bovis bacille Calmette-Guérin (BCG) to induce protection of brushtail possums against tuberculosis. To determine the duration of protective immunity following oral administration of BCG.

METHODS: In Study 1, a group of possums (n=7) was immunised by feeding 10 pellets containing dead Pasteur BCG, followed 15 weeks later with a single pellet of live Pasteur BCG. At that time, four other groups of possums (n=7 per group) were given a single pellet of live Pasteur BCG orally, a single pellet of live Danish BCG orally, 10 pellets of live Pasteur BCG orally, or a subcutaneous injection of live Pasteur BCG. For the oral pelleted vaccines, BCG was formulated into a lipid matrix, and each pellet contained approximately 10⁷ colony forming units (cfu) of BCG, while the vaccine injected subcutaneously contained 10⁶ cfu of BCG. A sixth, non-vaccinated, group (n=7) served as a control. All possums were challenged by the aerosol route with a low dose of virulent M. bovis 7 weeks after vaccination, and killed 7–8 weeks after challenge. Protection against challenge with M. bovis was assessed from pathological and bacteriological findings.

In Study 2, lipid-formulated live Danish BCG was administered orally to three groups of possums (10–11 per group), and these possums were challenged with virulent M. bovis 8, 29 or 54 weeks later. The possums were killed 7 weeks after challenge, to assess protection in comparison to a non-vaccinated group.

RESULTS: The results from Study 1 showed that vaccine efficacy was not adversely affected by feeding dead BCG prior to live BCG. Feeding 10 vaccine pellets induced a level of protection similar to feeding a single pellet. Protection was similar when feeding possums a single pellet containing the Pasteur or Danish strains of BCG. All vaccinated groups had significantly reduced pathological changes or bacterial counts when compared to the non-vaccinated group. In Study 2, oral administration of Danish BCG induced protection against challenge with M. bovis, which persisted for at least 54 weeks after vaccination. Some protection was observed in possums challenged 54 weeks after vaccination, but this protection was significantly less than that observed in groups vaccinated 29 or 8 weeks prior to challenge. There was a strong relationship between the proportion of animals producing positive lymphocyte proliferation responses to M. bovis antigens and protection against challenge with M. bovis.

CONCLUSIONS: Factors considered potentially capable of interfering with vaccination, including feeding dead BCG to possums prior to feeding live BCG, feeding multiple doses of BCG at one time, and changing strains of BCG, were shown not to interfere with the acquisition of protective immune responses in possums. Protection against tuberculosis was undiminished up to 29 weeks after vaccination with BCG administered orally. It is concluded that vaccination of possums by feeding pellets containing BCG is a robust and efficient approach to enhance the resistance of these animals to tuberculosis.     

内蒙古自治区区域协调问题与对策研究

内蒙古自治区与相关区域构成了一个复杂、开放的区域系统,其内部主要由自然区、行政区、主体功能区等组成;区域协调内容包括内蒙古自治区与全国的协调、内蒙古自治区东部与西部的协调、呼和浩特、包头、鄂尔多斯(简称呼包鄂,下同)三市协调、内蒙古自治区与俄罗斯等国家的协调、内蒙古自治区与相关省市自治区的协调、自然区与行政区的协调、行政区与主体功能区的协调、城市与农牧区的协调等;存在着许多社会经济指标低于全国平均水平、东部与西部社会经济等方面差距过大、出口依存度太低与外贸逆差过大、与相关省市自治区自然资源及产业的互补性差、地方利益与流域全局利益矛盾尖锐、主体功能区跨界缺乏统一领导、呼包鄂三市产业同构化现象趋于明显、城乡差距过大等问题;应该采取加强内蒙古自治区区域协调研究、编制区域协调规划、建立区域协调组织、利用调控手段促进区域协调发展和构建区域协调内在机制等对策.     

AMMI双标图在马铃薯区域试验产量分析中的应用

运用AMMI模型.结合双标图对2007年国家中晚熟西北组马铃薯品种区域试验各承试点的平均产量结果进行分析.试验结果表明,在参试品种中,L0031-17、青薯6号高产但不稳产,陇薯3号为高产稳产型,品种960102、中9931-48稳产但不高产,8025-1不稳产又不高产.AMMI模型具体、直观、有效的综合评价,为马铃薯品种提供了一种比较好的分析方法.     

马铃薯新品种青薯11号的选育

青薯11号是以同薯23号为母本,以青薯168为父本,通过有性杂交和系统选育育成的鲜食马铃薯新品种。中晚熟,出苗至收获107 d(天)左右;薯块椭圆形,粉红皮,薯肉黄色带红晕,芽眼浅;块茎淀粉含量17.96%,粗蛋白3.17%,VC240.3 mg·kg~(-1),还原糖0.279%。抗晚疫病。一般肥力条件下每667 m~2产量2 200~2 500 kg,高肥力条件下产量2 500~3 000kg。适宜在青海省各类地区种植。     

心痛方对心肌缺血模型大鼠MPO 活性 及PS 表达的干预作用

目的探讨心痛方对心肌缺血大鼠模型心肌梗死面积及髓过氧化物酶（MPO）、P 选择素（PS）的干预作 用。方法80 只清洁级SD 大鼠,随机分成假手术组、模型组、心痛方组、欣康组,采用结扎法造成心肌缺血模型,NBT 染色法测心肌梗死面积,比色法检测MPO 活性,免疫组化法检测PS 的表达。结果1.模型组、心痛方组、欣康组心肌梗 死面积、MPO 活性及PS 表达均显著高于假手术组,差异有统计学意义（P<0.01）;2.心肌梗死面积比较,心痛方组、欣康 组分别小于模型组（P<0.05）,差异均有统计学意义;3.MPO 活性比较,心痛方组、欣康组分别低于模型组（P<0.05）,而 心痛方组低于欣康组（P<0.05）,差异均有统计学意义;4.PS 表达比较,心痛方组、欣康组分别低于模型组（P<0.05）,差 异均有统计学意义。结论心痛方能缩小心肌梗死面积,抑制缺血心肌MPO 活性及PS 表达。在抑制MPO 活性方面心 痛方优于欣康。     

发酵与焙烤对可可豆香气影响的GC-MS分析

采用顶空固相微萃取（HS-SPME）和气-质联用仪（GC-MS）分析未发酵豆、发酵豆和焙烤豆的香气成分,并采用主成分分析法对可可豆香气的影响进行分析。结果表明：未发酵豆、发酵豆和焙烤豆香气差异明显。从未发酵豆和发酵豆中分别鉴定出30和62种挥发性成分,主要为醇类、酮类、烯烃类和醛类,发酵后可可豆香气物质增多。在105、125、145 ℃下焙烤的未发酵豆和发酵豆分别鉴定出47、59、84和71、68、83种,主要为醇类、酯类、醛类、烯烃和吡嗪类,低温焙烤和高温焙烤的可可豆香气差异明显;酮类集中于未发酵低温焙烤区,酸类、酯类和醇类偏向于发酵低温焙烤区,呋喃类和吡嗪类等杂环类化合物指向高温焙烤区。这些香气成分的差异,形成不同处理可可豆之间的风味差异,可可豆香气成分的主成分分析可以作为可可豆不同处理潜在的评价方法。     

日光温室牡丹花石榴光合特性研究

以LI-6400光合作用测定系统对日光温室牡丹花石榴的光合特性进行测定。结果表明,在晴天条件下,牡丹花石榴光合速率日变化呈双峰曲线,最高峰在8时,次峰在15时,中午有明显的“午休”现象。光合作用的光补偿点和饱和点分别为32μmol/m2/s和1200μmol/m2/s,CO2补偿点和饱和点分别为16μmol/mol和850μmol/mol。     

UV-Fenton法降解废水中苯酚的研究

［目的］探索紫外光助Fenton法降解废水中苯酚的效果。［方法］研究H2O2 和FeSO4 加入量、pH值及反应时间对苯酚降解率的影响。［结果] 试验结果得出,采用紫外光助Fenton法处理浓度为100 mg/L的苯酚废水,最佳条件为H2O2 浓度为3.0 mmol/L; FeSO4 浓度为0.3 mmol/L; pH值3.5。降解行为符合一级反应动力学,其反应速率常数为0.077 7 min^-1。［结论］UV-Fenton法是一种非常有效的去除废水中苯酚的方法。     

藿芪灌注液质量标准研究

目的建立藿芪灌注液质量标准.方法采用薄层色谱法对处方中淫羊藿、红花、丹参与益母草进行TLC定性鉴别;使用WondaSil C18柱(4.6mm×250mm,5μm),流动相∶乙腈-水(28∶72),柱温40℃,检测波长270nm,进样量10μL,流速1.0mL/min测定淫羊藿苷的含量;使用ZORBAX SB-C18柱(4.6mm×150mm,5μm),漂移管温度为90℃,载气流速为2.5L/min,流动相∶甲醇-水(65∶35),柱温40℃,流速1mL/min,用蒸发光散射检测器测定黄芪甲苷的含量.结果 TLC鉴别色谱图分离效果好,阴性对照无干扰,专属性强,重复性好;测定淫羊藿苷与黄芪甲苷含量表明,分别在2.336~58.4μg/mL(r=0.999 9)和0.047 8~0.478mg/mL(r=0.999 6)范围内与峰面积成较好的线性关系;其平均加样回收率分别为100.2%,RSD=0.45%和99.26%,RSD=1.46%.结论所建立的特征图谱专属性强、准确可行、简便、可快速用于定性鉴别、定量检测,可有效地用于该制剂的质量控制方法.     

电场处理油葵种子对其萌发期水分胁迫敏感性的影响

用不同电场强度处理油葵种子15min,以PEG(聚乙二醇)模拟水分胁迫,测定电场处理对种子萌发期抗旱性的影响.结果表明:在0～6.0kV/cm场强范围,不同电场强度,对种子水分胁迫的敏感性的影响程度不同.随着电场强度的增加,种子敏感性以振荡关系变化.适当电场处理条件能够显著地提高种子的吸水率,减轻细胞膜对干旱胁迫的敏感性,从而减小水分胁迫对细胞膜的伤害.提高种子抗旱性最佳电场处理条件的选取与处理时间和电场强度有关.