Showing papers by "North China Coal Medical University published in 1998"

Ultrastructural observation on the transformation of the spermatozoon in spermatogenesis of Taeniid cestodes.

Abstract: AIM: To study the transformation of taeniid spermatozoon during spermatogenesis on the ultrastructure level. METHODS: Transmission electronmicroscopy. RESULTS: This paper was the second part of the ultrastructural observations on the spermatogenesis in Taeniid cestodes: The transformation of the spermatozoon. The 64-spermatid-plasmodium was generated from the secondary meiosis of the 32 rose-like secondary spermatocytes. The transformation of the spermatozoon was a complex process. Firstly, both the cytoplasm and nucleus of the spermatid elongated while the cytoplasm increased and connected to the cytoplasmic mass (cytophore). Secondly, the chromatins of nucleus polymerized to a thread-bundle-like structure. Finally, it detached from the cytoplasm mass and became a mature spermatozoon. The mature spermatozoon was a thread-like structure, about 16.2-18.6 microns in length and 0.35-0.45 micron in diameter. There were two structurally distinct parts: the part with the nucleus was the head and the part without the nucleus was the tail. The head measured about 5-6 microns in length, 1/3 of the total body length and contained an elongated nucleus which twined around the axoneme without mitochondria. The tail was about 11.2-16.6 microns in length. Throughout the core of the tail was an axoneme with typical "9 + 1" structure. The anterior of the tail, just behind the head, were some mitochondria, about 1.6-1.7 microns in total length which twined around the axoneme. The posterior of the tail contained only an axoneme. In cross-section of the spermatozoon, about 46 microtubules were beneath the plasma membrane. CONCLUSION: The transformation of the spermatozoon is a very complex process.

Ultrastructural observation on spermatocytogenesis in Taeniid cestodes.

Abstract: AIM To study the spermatocytogenesis of taeniid cestodes at the ultrastructural leaves. METHODS Transmission electron microscopy. RESULTS The ultrastructural observation on spermatocytogenesis in Taenia solium, T. saginata and T. pisiformis were made by TEM. Two types of spermatogonia; type A and B, as well as the supporting cells surrounding the peripheral of spermatogonia are recognized. The type A spermatogonia are stem cells and the type B are mother cells which produce 16 primary spermatocytes by mitosis for 4 times with the cells unseparated. The primary spermatocytes are characterized by the ribosome masses in the cytoplasm. 32 secondary spermatocytes arranged in roselike were produced by reductive division of primary spermatocytes. The secondary spermatocytes become the spermatid quickly by short time development. CONCLUSION The dividing mode of spermatogonia in Taeniid cestodes is mitosis with cells unseparated.

Ultrastructural observations on the formation and metabolism of calcareous corpuscles in Cysticercus cellulosae.

Abstract: AIM To study the formation and metabolism of calcareous corpuscles from Cysticercus cellulosae at the ultrastructure level. METHODS Transmission electron microscopy. RESULTS The developmental processes of calcareous corpuscles could be divided into two stages: the intracellular formation stage and the extracellular metabolic stage. The calcareous corpuscles were formed in a cell which we named calcareous corpuscle forming cell. At the early stage of the formation, the corpuscles appeared to be secretory granules in the cells. With the development of the corpuscles, they became bead-shaped and lamellae-like, then the calcareous corpuscle forming cell enlarged and the organellae degenerated. Finally the corpuscles gathered to form particle substances with black dense background, while the nucleus and organellae of the forming cell all disappeared. There were 1-3 or 10-20 calcareous corpuscles in a mature forming cell. Then, the corpuscles were released to the parenchymal tissues and gradually appeared to be concentric lamella or an empty cavity during the metabolic process. CONCLUSION The calcareous corpuscles were formed in calcareous corpuscle forming cell and consumed in metabolic process in the parenchymal layer of Cysticercus cellulosae.

Detection of hemophilia A carriers by PCR analysis of hind III polymorphism in the factor VIII gene

Abstract: OBJECTIVE To explore a scheme of using PCR analysis in the detection of carriers of Hind III polymorphism of factor VIII gene of hemophilia A METHODS Implicating intron 19 of the factor VIII gene of 6 patients with the hemophilia A and 207 unrelated X-chromosomes were amplified by PCR and were analysed by means of Amp-RFLPs of Hind III RESULTS The incidence of the polymorphic Hind III sites in the given population was found to be 029 The frequence of the Hind III heterozygotes in women calculated according to Hardy-Weinberg equation was 041, which proved to be informative enough for carrier detection and prenatal diagnosis of hemophilia A 2 out of 6 families (33%)examined in this study were informative CONCLUSION The new scheme proved to be effective for hemophilia A carrier detection and prenatal diagnosis