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C J Hackett

Publications and source records attributed to C J Hackett.

41 records · Page 3Linked to original sources
PubMed1976

Ultrastructure of developing ascospores in Sordaria brevicollis.

The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity.

Ascomycota↗
PubMed1975

An introduction to diagnostic criteria of syphilis, treponarid and yaws (treponematoses) in dry bones, and some implications.

Diagnostic criteria of syphilis and some other diseases are proposed from a study of 424 crania and calvariae and 250 long bones in 22 medical museums in Europe. Yaws bone lesions in Uganda and changes in Australian aboriginal bones also contributed to the establishment of these criteria. Any deductions about disease in the past or isolated populations must depend upon acceptable diagnostic criteria; post mortem damage must be recognised. In crania and calvariae the sequence of changes of Virchow's caries sicca, and in long bones nodes/expansions with superficial cavitation are sound indicators of syphilis, and of yaws and treponarid in relevant geographical areas. Attention is called to the cause of sequestra in European calvariae labelled syphilis, the absence of sequestra due to haematogenous pyogenic osteomyelitis in Australian and other aboriginal bones and possibly in Europe before the Middle Ages. The number of bones with diagnostic criteria needed to demonstrate the endemicity of a particular infection in a past community is discussed. There is also need for an extensive application of diagnostic criteria of syphilis to pre-Columbian or pre-European bones everywhere. The uncertain future of old dry diseased bones in medical museums, and the need for reference centres to provide sound advice and guidance in palaeopathology are stressed.

Bone and Bones↗