Occurrence of Cucurbit Yellow Stunting Disorder Virus (CYSDV) and Beet Pseudo-yellows Virus in Cucurbit Crops in Spain and Transmission of CYSDV by Two Biotypes of Bemisia tabaci

The relative occurrence in Spain of two whitefly transmitted closteroviruses causing similar yellowing diseases in melon and cucumber greenhouse crops was studied. Based on a RT-PCR assay, a 1994–1997 survey of Spanish greenhouses showed that the recently described Bemisia tabaci-transmitted cucurbit yellow stunting disorder virus (CYSDV) has displaced the Trialeurodes vaporariorum-transmitted beet pseudo-yellows virus (BPYV), a virus that was present in the area since the late 1970s. The CYSDV transmission rates by each of the two biotypes of B. tabaci present in Spain were compared. The results showed that the ubiquitous B biotype and the resident Q biotype (found in Spain and Portugal) were able to transmit CYSDV with similar efficiency.     

Use of the carbon dioxide laser for perianal and rectal surgery.

The skin of the perianal region is very thin and sensitive. The carbon dioxide laser is a very effective tool for removing tumors and treating conditions of this area. It offers a "no touch" method of treatment for conditions of the perianal region. There is less bleeding, less pain, less swelling with the use of the carbon dioxide laser. The carbon dioxide laser is an effective tool for excising perianal tumors, rectal tumors, performing anal sacculectomies and treating perianal fistulas.     

Larynx-associated lymphoid tissue (LALT) in young cattle

This paper describes the presence of lymphoid tissue in the mucosa of the bovine larynx. A total of 15 bovine larynges were examined both macroscopically after tissue fixation in acetic acid and microscopically using histology. It was found that no paraepiglottic tonsil was present in cattle, although a few lymphoid follicles were present in the mucosa at the base of the epiglottis. This result is in accordance with previous reports. In contrast, numerous lymphoid follicles were seen in the mucosa of the epiglottis and the corniculate processes of the arytenoid cartilages. This suggests that larynx-associated lymphoid tissue is present in cattle. Our observation could be of clinical importance, e.g. in the framework of the development of aerosolized vaccines.     

Dogs as vectors of Streptobacillus moniliformis infection?

Rat bite fever is a bacterial zoonosis transmitted through the bite of rats. One of the two etiological agents that cause rat bite fever is Streptobacillus moniliformis. Rat bite fever is rare and very likely under diagnosed but occurs worldwide. Other animals, like dogs and cats that have mouthed a rat are often mentioned in the literature as potential risks for the attraction of rat bite fever. However, rat bite fever caused by the bite of a dog or cat has very seldom been documented. Therefore, to identify the possible risk for humans to become infected with S. moniliformis after having been bitten by a dog that has been in contact with rats, the presence of S. moniliformis in the mouth of these dogs was tested with molecular methods. Swabs taken from the mouth of 18 dogs with proven contacts with rats were tested for the presence of S. moniliformis DNA by PCR. An amplicon of the right size was obtained in 10 of the 18 dogs. Nucleotide sequencing of five amplicons of PCR positive samples demonstrated the presence of S. moniliformis DNA in the mouth of three dogs. A bite by these dogs therefore might infect humans with S. moniliformis and cause rat bite disease.     

Anatomical and histological aspects of the bovine lingual tonsil

The localization of the bovine lingual tonsil is described as a prerequisite for the removal of specified risk material from the tongue meat in order to restrict the risk arising from bovine spongiform encephalopathy (BSE) to public health. The major part of this tonsil can be located macroscopically by the openings of its follicular crypts at the root of tongue. This part consists of organized aggregations of lymph nodules. Additional solitary primary lymph nodules and diffuse accumulations of lymphocytes are macroscopically invisible but are bilaterally present in the area extending 2 cm caudal to 3 cm rostral to the last vallate papillae. By sectioning the tongue 3 cm rostral to the last vallate papillae, undermining the lingual mucosa to the level of these papillae and making a transverse cut towards the lingual process of the basihyoid bone, the greater part of the lingual tonsil can efficiently be removed. Finally, immunohistochemical staining demonstrated the presence of T and B lymphocytes, suggesting that the bovine lingual tonsil can be considered as a site where an immune response can be induced.     

Development of the conservation of Dutch coastal waters

1. Traditionally, the living and nonliving natural resources of the coastal waters of The Netherlands have been exploited. Part of this exploitation took the form of embankment and reclamation to produce new agricultural land. 2. The first nature reserve within the coastal waters was established in 1916. After this year the number of coastal nature reserves gradually increased. However, until about 1970 the status of a nature reserve provided little protection when other interests claimed the same area. 3. In the period 1965–1980 the situation changed drastically. The Dutch government took far-reaching decisions with regard to the protection of the Wadden Sea and the Oosterschelde estuary. 4. At the start of this century about 10 000 km² of coastal waters existed between the mainland coast and the three-miles territorial border of The Netherlands. Of these, 4500 km² have been embanked and reclaimed or changed into freshwater lakes, 4000 km² have protected status, and about 1500 km² within the former three-miles zone and in the Westerschelde estuary (250 km²) are still unprotected. 5. The present situation with regard to the conservation of coastal waters in The Netherlands is largely due to private initiatives. Scientists played an active part in the conservation movement by providing information, especially in the early phases of this development. © 1997 John Wiley & Sons, Ltd.