Mixed infection with type 2 poliomyelitis virus and Columbia SK group virus in man; an attempt to explain any relation of viruses of the Columbia SK group to human poliomyelitis

Summary Two virus strains isolated from stools of poliomyelitis patients were apparently a mixture of a type 2 strain of poliomyelitis virus, and of a strain of the Columbia SK group of viruses. Both components of the E.S. strain could be separated by neutralization of second passage cynomolgus monkey cord with either Lansing or Columbia SK hyperimmune serum. A similar technique with the 19th monkey passage of the A.K. strain failed to separate the components of this strain, which is suggested to be due to interference. Under experimental conditions, the murine A.K. strain was shown to interfere with the simian A.K. strain. Similarly, the original Columbia SK virus interfered with the Aycock strain of type 2 poliomyelitis virus. No interference was observed between the murine A.K. strain and types 1 and 3 poliomyelitis virus. Aided with a grant from the National Health Research Council T.N.O., The Hague, and from the Dr Simon Baruch Foundation, New York. W. H. O. Fellow, on leave of absence from the Université Libre de Bruxelles.     

Photosynthesis and predisposition of plants to infection with certain viruses

The effects on susceptibility to infection with certain viruses of subjecting plants to various periods of darkness or reduced illumination before and after inoculation were tested. The viruses and hosts used were a tobacco necrosis virus in French bean and tobacco; tomato aucuba mosaic virus in tobacco; and tobacco mosaic and tomato bushy stunt viruses in Nicotiana glutinosa . All the virus-host combinations give necrotic local lesions, and susceptibility was measured by local lesion counts. Susceptibility was consistently increased by pre-inoculation treatments of host plants, whereas post-inoculation treatments had relatively little effect, but most often decreased susceptibility.
Short periods in the dark produced similar responses to longer periods in shade, but the different plants varied in their response to, and tolerance of, darkness. The maximum number of lesions was usually obtained with bean plants kept for only 24 hr. in the dark before inoculation, but with tobacco plants susceptibility increased with increasing time in the dark up to 5 days.
It is suggested that the successful establishment of infection occurs in two stages, the first of which is affected by. the accumulation of photosynthetic products. Whether these products confer resistance by increasing cell turgor or by reacting specifically with virus particles is unknown, but sap from plants in the light possesses no greater virus-inhibiting power than sap from plants kept in the dark.     

淋病奈瑟菌感染实验室检测技术的进展

细菌培养是诊断淋病奈瑟菌(NG)感染的"金标准",也是目前诊断淋病最可靠的方法.但淋病奈瑟菌在人体外抵抗力极弱,不易培养;仅做细菌形态学检查,诊断意义有限.随着淋病奈瑟菌耐药性不断增强,多重耐药菌出现并广泛传播.高敏感性、高特异性、操作简便的分子生物学检验技术,如单管多重聚合酶链反应(PCR)技术等,已开始用于淋病奈瑟...