Morphology of the uterus of Ascaris lumbricoides in the region where fertilization and formation of egg-shell occur.

Morphology of the female reproductive system of Ascaris lumbricoides L. was studied in the region starting with the junction between the oviduct and the uterus (O-U) up to the junction of both uterine branches into the vagina with regard to the process of fertilization and formation of egg-shells. In the O-U junction morphology differed in two following sections: a continuous simple squamous up to simple cuboidal epithelium, and simple cuboidal up to columnar epithelium with broad intercellular spaces leading into the lumen of the tubular reproductive organ filled with sperm.

Colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium Goddard.

The process of colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium was studied by scanning electron microscopy. The preparations were made by fractionation of egg suspension exposed to the fungus for four days and frozen in liquid nitrogen according to Stĕrba and Milácek (1986). Ovicidal fungus forms an abundant ramifying mycelial network in the area between the eggs.

Visualization of chitin-protein layer formation in Ascaris lumbricoides egg-shells.

The formation of chitin-protein layer in Ascaris lumbricoides egg-shells was studied using the method of chitin structures visualization by means of derivatives of stilbene-disulfonic acid (Blankophor, Bayer, FRG). Intensive formation of chitin structures in A. lumbricoides egg-shell occurred only in fertilized females in a very short portion of uterus from the site of connection of the oviduct with the uterus up to 25-30 mm distally, i.

Diploids of ovicidal fungus Penicillium lanosum.

By use of auxotrophic mutants of Penicillium lanosum were prepared the heterokaryonts. From more rapidly growing sectors from heterokaryotic mycelium on minimal medium were isolated 17 diploid strains. They were prototrophic and on the whole they did not differ from the wild strain in their morphology and their growth rate.

[The autodehelminthizing capacity of the soil].

A description of the methodology used for the study of soil deshelminthizing processes is presented, as well as some of the results already obtained. This method has already been tested on the soil of different countries, including Mexico, and it is still in an experimental stage; notwithstanding, the results obtained are encouraging. Further research is needed for its successful application as a tool on the control of human soilborne diseases.