Bovine adenoviruses—IV. Two mixed antigens for routine serodiagnosis by complement fixation reaction

The frequency of bovine adenovirus infections occurring in cattle has been grossly underestimated up to the present day. Primary isolation of serotypes belonging to bovine subgroup II is cumbersome. Hardly any laboratory has used all 8 officially-recognised bovine serotypes in seroneutralisation-tests, which should be done when this type-specific method is used for serodiagnosis. The complement fixation test, known as group-reactive from human adenovirus serology, has failed to disclose the true incidence of bovine infections, as until recently the importance of a novel additional group-reactive bovine adenovirus antigen had been undisclosed. Here we describe production, composition and performance of two mixed antigens for complement fixation reactions, which take into account recent findings by our team on peculiarities of bovine adenovirus antigens. Mixed antigen 1 contains bovine serotypes 1, 2 and 3 and detects group-specific antibodies of the classical mastadenoviruses. Mixed antigen 2 contains bovine serotypes 4, 5, 6, 7 and 8 and determines group-specific antibodies against the novel paramastadenoviruses. In addition, each antigen is capable of demonstrating complement-fixing type-specific antibodies in sera against the respective types included in each mixed antigen, with a net enhancing effect produced by mixing. Use of the 2 mixed antigens promptly shows whether bovine adenoviruses, presently recognised as well as unclassified, are involved in a given outbreak of respiratory or enteric disease of cattle. If needed, the responsible type may be determined in a second step of serological investigation.     

毛竹竹材几个热力学特性参数的测试与分析

采用闪光法和比较法及直线法分别测量了毛竹竹材沿垂直竹纤维方向的几个热力学特性参数:热扩散率α、比热Cp及竹材密度ρ, 并根据公式λ= 418.68 α Cp ρ得出其另一个重要的热力学特性参数--导热系数λ.结果表明:竹材的热扩散率α与竹材生长的方向和高度的关系不大;导热系数λ、热扩散率α、比热均Cp在温度为70℃左右时具有最大值.这一结果对竹材的热处理加工具有一定的指导意义.     

Serologic response to Brucella abortus of cattle and guinea pigs experimentally inoculated with a Yersinia enterocolitica serotype from milk

Ten strains of Yersinia enterocolitica belonging to ten various serogroups isolated from raw milk were inoculated into groups of five guinea pigs and five calves. Y. enterocolitica serotype 0:16 was the only serotype tested that induced an antibody response to Brucella abortus in calves. No anti-Brucella response could be demonstrated serologically in guinea pigs. Activity of the anti-Y. enterocolitica 0:16 calf sera against B. abortus antigen was shown by the tube agglutination test, and by the complement fixation test. The early agglutinating antibody response was partly sensitive to reduction by 2-mercaptoethanol. This sensitivity decreased later in the response. This is the first report of anti-Brucella responses induced by a serotype of Y. enterocolitica other than 0:9; sera from a group of five calves inoculated with 0:9 were tested by the same serological techniques for comparison.     

Current status of leptospirosis in Japan and Philippines

Leptospirosis is an acute febrile illness with a wide variety of clinical manifestations and is encountered throughout the world, prominently in tropical areas with high rainfall. In this paper, we review the current status of leptospirosis in two Asian countries, Japan and Philippines, which have quite different situations in terms of economy, environment, infrastructures and prevailing infectious diseases. In Japan, until 1960, more than 200 deaths due to leptospirosis had been reported yearly. After 1960, the number of reported cases had rapidly decreased. Now, leptospirosis cases notified every year were less than 20. After the early 1960s, modernization of agriculture was introduced, at the same time, inactivated vaccine against Leptospira was applied for humans and there was good maintenance of infrastructures such as water works and sewage systems.

In Philippines, on the other hand, leptospirosis patients tend to be frequently found in flood-prone areas of urban setting such as Metro Manila, which was found to be the endemic foci of leptospirosis. Morbidity in a rural area (Cabatuan, Iloilo) was 147 cases per 100,000 populations. From 1998 to 2001, about 70% of 1200 suspected leptospirosis patients in Philippines were serologically positive. The average age of patients was 32 years old where 87% of the cases were males and 70% were outdoor workers. Case fatality rate was found to be 12–14%. The estimated major serovars in Metro Manila and neighboring provinces were Manilae, Losbanos, Tarassovi, Poi and an unknown serovar. Outbreaks of leptospirosis in the Philippines are thought to be associated with heavy rainfall, rapid urbanization (dramatic increase in populations), deforestation, increasing number of flood-prone areas, poor infrastructures and many others.     

核盘菌对几种杀菌剂的敏感性研究

为了选择防治菌核病的有效药剂,采用FAO推荐的菌落直径法研究了常用杀菌剂对核盘菌敏感性的差异。结果表明:山西五寨菌株WZ2对腐霉利、多菌灵、菌核净、福美双、乙霉威、乙烯菌核利高度敏感(EC50在0.117 0~4.965 4μg.mL-1之间);对异菌脲中度敏感(EC50为5.069 0μg.mL-1);对代森锰锌和百菌清最不敏感(EC50为20.760 0,32.107 6μg.mL-1)。内蒙古菌株NM15和NM17均对腐霉利、多菌灵、菌核净、福美双、乙烯菌核利高度敏感(EC50在0.064 0~3.059 0μg.mL-1);对乙霉威、异菌脲中度敏感(EC50为7.330 7~13.823 4μg.mL-1之间);对代森锰锌最不敏感(EC50分别为37.645 3,42.303 0μg.mL-1)。另外,菌株NM15对百菌清高度敏感(EC50为2.104 8μg.mL-1),而NM17则对百菌清中度敏感(EC50为11.777 9μg.mL-1)。并且这三个菌株对腐霉利、百菌清的敏感性差异较大,而对其他药剂的敏感性差异不大。     

植物细胞的分化与脱分化

细胞分化与脱分化是现代生物学的基本问题之一。综述了植物细胞分化、脱分化过程中的形态结构变化及其调控。结果表明：从形态结构水平很难找出标志细胞分化与脱分化的特征规律。激素被证明对细胞分化与脱分化的调控起作用。生长素与细胞分裂素的作用受到普遍的关注。参18。     

基于小波变换的语音信号去噪

利用小波的时频域局部化特性,解决语音信号的去噪问题。文中给出了语音信号的小波去噪算法,并基于不同的阈值选取,提出了采用适合于语音信号的浮动阈值,实验表明去噪效果好,提高了语音信号的识别率。     

Etude par spectrometrie de masse a etincelles de la composition minerale de cuticules isolees de feuilles de poirier passe crassane

Abstract

The minerai content of enzymatically isolated pear leaf cuticles has been determined using a technique allowing a high sensitivity and a wide elemental coverage : the spark source mass spectrometry. About thirty elements have been detected, classified in different classes according to their content : N, K (major) Ca, Si, Al, Na (≥ 1 000 ppm) Fe, Cl, Mg (≥ 100 ppm) P, Cu, Zn, Ti, Ba, Mn, Ni, Co, Sr (≥ 10 ppm) B, Ag, Rb, Cr, Sn, V, Pb, Cd, U etc... (traces). These results are compared with analysis of entire pear leaves effected simultaneously and with those reported in literature concerning isolated tomato fruit cuticles. The problem of their validity for cuticles in situ, is discussed.     

Composition and biological activity of the essential oil from Thapsia minor, a new source of geranyl acetate

The essential oils from aerial parts of Thapsia minor Hoffmanns. & Link (Apiaceae), obtained by hydrodistillation, were analyzed by gas-chromatography and gas-chromatography-mass spectrometry. Oxygenated monoterpenes represented the main fraction with geranyl acetate (82.3-83.0%) as the major constituent, making this plant a good source of this compound.Biological activity of the essential oil was evaluated against several fungal strains. The highest activity was found against dermatophyte strains, Crytococcus neoformans and Candida guillermondii with minimal inhibitory concentrations values from 0.32 μl/ml to 1.25 μl/ml. The antifungal activity could be associated with the significant contribution of the oxygenated monoterpene geranyl acetate.Furthermore, this essential oil demonstrated to have potent anti-inflammatory in vitro activity, at concentrations that did not affect macrophages and keratinocytes viability, being the anti-inflammatory properties of the oil mainly due to geranyl acetate.These favorable results emphasize the antifungal and anti-inflammatory abilities of the molecule geranyl acetate and further support the exploitation of T. minor oil for pharmaceutical industry, in order to find new phytopharmaceuticals.     

异色瓢虫显明变种对白杨毛蚜和白毛蚜选择效应研究

[目的]探究异色瓢虫显明变种对杨树主要蚜虫白杨毛蚜和白毛蚜的捕食选择趋性。[方法]在实验室条件下,在特定空间内,测定异色瓢虫显明变种对2种蚜虫不同密度值下的捕食量。[结果]白杨毛蚜和白毛蚜种群数量同步增加时,EG-S值和EJ值变化为＋1～0,EI值是在0～-1范围内依次减少,且数值变化幅度较少,表明异色瓢虫显明变种喜好捕食白毛蚜略高于白杨毛蚜;当白杨毛蚜数量不变、白毛蚜数量增加时,EG-S值和EJ值变化为＋1～∞,EI值在0～＋1范围内依次增加,表明异色瓢虫显明变种明显喜好捕食白毛蚜;当白毛蚜数量不变、白杨毛蚜数量增加时,EG-S值和EJ值变化为在＋1～0范围内依次减少,EI值在0～-1范围内依次增加,表明异色瓢虫显明变种明显喜好捕食白杨毛蚜。捕食量结果同选择指数。[结论]异色瓢虫显现变种白杨毛蚜和白毛蚜的捕食选择趋性取决于2种蚜虫的种群数量。