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X M Tang

Publications and source records attributed to X M Tang.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Cytochemical studies on the formation of multivesicular bodies in Leydig cells].

Multivesicular bodies were observed frequently in electron microscope photographs of Leydig cells from normal adult rat testes. Their formation, evolution and fate were analyzed morphologically in preparations treated to show cytidine monophosphatase (CMPase) activity and in animals sacrificed at various time intervals ranging from 5 min to 2 hrs after a single intratesticular injection of cationic ferritin (CF). Analysis of morphological and cytochemical data led to the following interpretation for the origin and fate of the multivesicular bodies in Leydig cells. The formation of multivesicular bodies in Leydig cells can be divided into three steps. Step 1, some endocytic vacuoles in Golgi region fuse with small vesicles to form pre-multivesicular bodies. Step 2, the pre-multivesicular bodies fuse together to form pale multivesicular bodies which are characterized by their large size, pale matrix and paucity of internal vesicles. Step 3, the pale multivesicular bodies remove their surplus enveloping membrane to become dense multivesicular bodies which are characterized by their smaller size, dense matrix and filling with internal vesicles. The pre-multivesicular bodies and pale multivesicular bodies do not contain hydrolytic enzymes, the dense multivesicular bodies acquire their hydrolytic enzymes by fusion with lysosomes and show CMPase activity. The dense multivesicular bodies often show a very close association with autophagosomes, and they might be involved in the autophagic activity of Leydig cells.

Animals↗
PubMed1990

Ultrastructural study of hip joint osteoarthritis. Scanning electron microscopic study of articular cartilage of femoral head.

The surface structure of four different articular cartilages of the femoral head was studied with scanning electron microscope in 12 cases of hip joint osteoarthritis. These articular cartilages were mink white, yellow, dusky red and hyperplastic and thickened. The osteoarthritic articular cartilage surface was uneven with puckerings of various height, width and orientation. The puckerings were covered with fibril network. The fibrils were exposed collagen fibrils and of different diameters. Wider fiber bundles without orientation were found on the fibril network. On the surface of the hyperplastic articular cartilage observed were many deep and oval spaces left behind after breakdown of the lacunae of cells in the clusters of articular chondrocytes. In the spaces, remnants of articular chondrocytes were seen.

Cartilage, Articular↗
PubMed1990

Ultrastructural investigation of granulation tissues on the osteoarthritic femoral head. A scanning electron microscopic and transmission electron microscopic study.

From the femoral heads of nine cases of advanced osteoarthritis of hip joint, three categories of granulation tissues with different colors (bright red, dark-red and white granulation tissues) and texture were obtained. After processing, the specimens were observed under scanning electron microscope and transmission electron microscope. With transformation of the granulation tissues from bright red to white, the collagen fibers therein contained gradually changed from fine to thick ones. Nevertheless, the cellular components in these three types of granulation tissues always possessed the characteristics of both fibroblasts and chondrocytes, i.e., fibroblastic configuration with pericellular Type I collagen fibrils bearing 64 nm periodicity; and chondrocytic scallop-shaped cytoplasmic membrane with intracytoplasmic fat droplets and glycogen granules and pericellular Type II collagen fibrils. All these indicated that in osteoarthritis of hip joints, the granulation tissues of the femoral heads transformed eventually into fibrocartilage, irrespective of their color and texture.

Femur Head↗
PubMed1989

Granule formation and polarity of the Golgi apparatus in neutrophil granulocytes of the rat.

The formation of granules in neutrophil (heterophil) progenitor cells was examined with the electron microscope in sections of rat bone marrow fixed in 2% glutaraldehyde and postfixed with reduced osmium (Karnovsky: Proceedings of the 11th Meeting, American Society of Cell Biologists, Abstr. 284, p. 146, 1971). The cells were also osmicated in 2% osmium tetroxide for 36 hours at 37 degrees C to outline the osmiophilic element usually observed on the cis-face of the stacks of saccules of the Golgi apparatus of various cell types. In myeloblasts, which do not produce granules, the cis-osmiophilic element (CE) was found on the concave face of the C-shaped Golgi stacks. In promyelocytes the CE was present on the convex aspect of the C-shaped stacks, while the primary (azurophilic) granules formed in relation to elements on the concave aspects of the stacks. In myelocytes, the situation was reversed: the CE was found on the concave face of the Golgi stacks, while the secondary (specific) granules were seen forming in relation to elements on the convex aspect of the stacks. Finally, in metamyelocytes and mature neutrophils in which no granule formation took place, the appearance on Golgi stacks varied: they were either flat or C-shaped. The CE was indiscriminately found on one face or the other of the flat Golgi stacks of metamyetocytes and on the convex or concave faces of the C-shaped Golgi stacks of mature neutrophils. Using the cis-osmiophilic-element as a marker of the cis-face of the stacked Golgi elements, it thus appeared that despite marked changes in the configuration and orientation of the stacks of the cis-trans polarity of the stacked elements was maintained throughout granulopoiesis. In addition the primary and secondary granules that appeared sequentially in promyelocytes and myelocytes were both seen to form in relation to trans-elements of the Golgi apparatus.

Animals↗
PubMed1989

Effect of intra-articular fracture on articular chondrocytes. A transmission electron microscopic study.

Intra-articular fractures involving the subchondral bone were produced surgically in both left and right medial femoral condyles of twenty rabbits. The edges of the fractures on the left side were well approximated, while those on the right side maintained with a gap of 2 mm. Transmission electron microscopic study of the nearby articular cartilages conducted 1, 2, 3, 4 and 5 months after the fracture revealed the following results: 1) The neighbouring articular chondrocytes tended once to assume the configuration of fibroblasts; 2) Those remote from the fracture showed both degeneration and hyperplasia to form clones; 3) Even after the intra-articular fractures were well-healed, degeneration and hyperplasia of the articular chondrocytes nearby the fracture would persist for some time.

Animals↗
PubMed1989

Immunological studies on thromboangiitis obliterans.

Using humoral immunity (gamma-globulin 18 cases, IgG, IgA, IgM each 30 cases, CH50, C3, C4 each 29 cases and CIC 31 cases), cellular immunity (E-RFC 68 cases, As 30 cases, SmIg, SmIgG each 18 cases, IMIT 30 cases) and immunopathological manifestations (light microscope, fluorescence microscope, transmitted electron microscope each 7 cases) as indices, we studied the immunological changes of "progressing", "remittent" and "stabilized" groups of patients with thromboangiitis obliterans (TAO) in different stages. Humoral immunity indicated that gamma-globulin, immune complex and IgG were all increased; cellular immunity indicated that the rate of T cells and suppressor cells was declined, while that of B cells was elevated. Immunopathologically, under light microscope all the layers of involved vessels were infiltrated with neutrophils, lymphocytes and monocytes; under fluorescence and electron microscope, immune complexes were found in the involved vessel walls. Our preliminary results suggest that TAO is an autoimmune disease relevant to antigen-antibody complex.

Adult↗
PubMed1989

Radioautographic findings in osteoarthritic femoral head.

During total hip replacement for 8 patients with hip joint osteoarthritis specimens of femoral articular cartilages of 3 types of involvement were taken, i.e. the "normal" articular cartilage, the fissured and wrinkled articular cartilage, and the yellow or dusky red, markedly thickened, and roughened articular cartilage. Radioautographical studies with 3H-Thymidine labelling showed the clusters of articular chondrocyte, degeneration, death and vanishing of the chondrocytes with empty lacunae left; and mitosis and proliferation of the chondrocytes, as evidenced by silver granules in the nuclear area. In the articular cartilages of three types of involvement, the percentages of degenerated, dead and vanished chondrocytes represented by empty lacunae, of non-mitotic chondrocytes without silver granule and of chondrocytes undergoing mitosis with silver granules, were 19.9, 38.3 and 41.8; 9.1, 48.9 and 42; 5.3, 35.0 and 59.7 respectively. A large number of empty lacunae appeared in the "normal" articular cartilage, signifying aging of the cartilage. Chondrocytes bearing silver granules appeared not only in the "normal" articular cartilage but also largely in the severe osteoarthritic cartilage and served as a compensatory manifestation of both aging and osteoarthritis.

Aging↗
PubMed1989

Electron radioautographic study of experimental fracture healing.

The mitotic activities of various cellular components of callus tissues in different periods after tibial fracture of rat were studied with 3H-thymidine labeling and electron radioautographic method. Silver grains were accumulated over the nuclear areas of mesenchymal cells, monocytes, macrophages, endothelial cells of capillaries, fibroblasts, chondroblasts and chondrocytes, as a result of incorporation of the labelling material during their mitosis. Although osteoblasts and osteocytes could not undergo mitosis, they also revealed silver grains over nuclear areas because of their derivation from the mesenchymal cells or osteogenic cells.

Animals↗
PubMed1989

[Cytolytic action of normal human natural killer cells on CNE-2 nasopharyngeal carcinoma cell in vitro].

Cytolytic actions of human natural killer cells, which were separated with nylon wool column from normal human peripheral blood, were investigated on human nasopharyngeal carcinoma cell line cells (CNE-2) and the dynamic processes of conjugation and cytolysis were studied. It was found that NK cells attacked living target cells and the course of cytolysis might be divided into 2 types according to their rapid or slow responses. In addition to the large granular lymphocytes the non-granular lymphocytes also participated in NK functions.

Humans↗
PubMed1986

Effect of CO2 laser irradiation on experimental fracture healing: a transmission electron microscopic study.

The healing of standardized fracture of rabbit radius was expedited as a result of treatment with low-power CO2 laser irradiation. Observation with transmission electron microscope revealed the following favorable effects of CO2 laser irradiation: The red blood cells were induced to disintegrate, thus promoting the absorption of the hematoma. The macrophages emerged early and increased in number so that debridement of the necrotic tissues was enhanced. The fibroblasts were more active in producing the fibrous callus. The chondrocytes were unusually active in forming bone tissues. The early and sustained appearance of osteoclasts favored the bone remodeling process. Increased capillary formation endowed the fracture healing with rich blood supply. Deposition of calcium salts took place early.

Animals↗