PubMed Health⌕ Search

Biomedical subjects

John Wachira

Publications and source records attributed to John Wachira.

2 recordsLinked to original sources

Ultrastructural study of Echnococcus granulosus larval forms.

The larval forms of Echinococcus granulosus were surgically removed from Turkana hydatid patients and studied on the electron microscope. It was found that the larval forms "hydatid cyst" consists of a protective laminated layer that surrounds the germinal layer. The germinal layer is made up of numerous germinal cells that transform to brood capsules within which protoscolices are formed. Protoscolices are formed from accumulations of undifferentiated germinal cells. The brood capsule wall is similar to germinal layer and they were found to contain numerous invaginated protoscolices. The invaginated protoscolices were of various sizes and they were not attached to the wall of the brood capsule. The evaginated protoscolex has two body regions, the head (scolex) and body (soma). The scolex is covered by numerous long microtriches whereas the soma is covered with few short microtriches.

Journal Article↗

Cellular immunity to Echinococcus granulosus cysts.

A fundamental feature of Echinococcus granulosus infection is its chronicity. There are many reasons for this, including weak natural immunity and the ability of the larval stages to evade or resist elimination by the hosts' specific immune responses. To identify the types of hosts' cellular immune response, a series of ultrastructral studies of hydatid cysts surgically removed from Turkana patients was conducted based on transmission electron microscopy. Ultrastructurally, the ectocyst (adventitial layer) is organised into three layers; an inner layer containing mainly the infiltrating mononuclear leukocytes; a middle, loose connective tissue layer with inflammatory cells mainly plasma cells, fibroblasts, scant neutrophils, eosinophils and lymphocytes, and an outer loose connective tissue layer that blends with the surrounding host tissue. The mast cells and basophils were not observed. This study has showm that the adventitial layer of hydatid cysts infiltrated by leukocytes, principally by macrophages and plasma cells.

Journal Article↗