Seventy-eight symptomatic females without palpable breast lumps were subjected to bilateral four quadrant fine needle aspiration cytology. Cytological evidence of an epithelial proliferative lesion was seen in 44 of these cases. Based on the cytological evidence of proliferation, the site for open biopsy was determined. Histopathological study of the breast biopsies in these patients showed proliferative disease without atypia (PDWA) in 40 cases, atypical ductal hyperplasia (ADH) in two, atypical lobular hyperplasia (ALH) in one and ADH with ALH in one case. Cytology was thus useful in establishing the presence of proliferative activity, commenting on the extent of proliferation, and thereby roughly mapping out the area of the breast most suitable for biopsy. On cytological grounds, it was not possible to distinguish the atypical hyperplastic lesions from the proliferative diseases without atypia.
Sporulation of Clostridium bifermentans serovar malaysia, which has a larvicidal activity towards mosquitoes, was examined by electron microscopy. Parasporal inclusion bodies lacking a crystalline structure were first detected at t5 (5 h after the end of exponentional growth). Also, the presence of "brush-bottle"-like appendages appearing first at t5 was noted; these remained attached to the spores when released after sporangium lysis. Larvicidal activity assayed on Anopheles stephensi larvae appeared at t0 and increased rapidly to a maximum between t5 and t8. However, a decrease in bacterial toxicity occurred with sporangium lysis.
The karyotypes have been determined of 16 of the 32 species of the genus Varanus, including animals from Africa, Israel, Malaya and Australia. A constant chromosome number of 2n = 40 was observed. The karyotype is divided into eight pairs of large chromosomes and 12 paris of microchromosomes. A series of chromosomal rearrangements have become established in both size groups of the karyotype and are restricted to centromers shifts, probably caused by pericentric inversion. Species could be placed in one of six distinct karyotype groups which are differentiated by these rearrangements and whose grouping does not always correspond with the current taxonomy. An unusual sex chromosome system of the ZZ/ZW type was present in a number of the species examined. The evolutionary significance of these chromosomal rearrangements, their origin and their mode of establishment are discussed and related to the current taxonomic groupings. The most likely phylogenetic model based on chromosome morphology, fossil evidence and the current distribution of the genus Varanus is presented.