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Biomedical subjects

J Qu

Publications and source records attributed to J Qu.

96 records · Page 6Linked to original sources
PubMed1992

Inhibin production and secretion in human placental cells cultured in vitro.

In this study, human trophoblast cells were isolated from term placentas by trypsin-DNase digestion and Percoll gradient centrifugation. After the cells were cultured in vitro, bioactive inhibin and immunoreactive inhibin were measured in the culture medium and cellular lysate by an ovine pituitary cell culture system and an immunoenzymatic assay. The trophoblast cells were capable of producing inhibin, as indicated by the observation that enhancement of inhibin content and secretion was dependent upon the cell number and time in culture. High levels of inhibin were observed in the culture medium and the cellular lysate with cell numbers of over 1 x 10(6) cells/well, whereas the inhibin levels decreased until they were nearly undetectable when the cell number was less than 0.25 x 10(6) cells/well. In the culture medium, a sharp increase of inhibin levels was observed after 2 days of culture. Bio-inhibin and immuno-inhibin concentrations in the culture medium increased tenfold and fourfold, respectively, from day 2 to day 4. The peak level of bio-inhibin (3.5 U/mL) occurred on day 4 and that of immuno-inhibin (3.55 U/mL) on day 6. In contrast, the maximal level of bio-inhibin (4.45 U/mL) and immuno-inhibin (4.25 U/mL) in the cellular lysate was observed on day 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Separation↗
PubMed1990

[Relationship between development of periodontitis and macrophage's defensive power against infection in rats fed a high-sucrose diet].

As mononuclear phagocytes have been implicated as important cellular elements in the process of bone resorption, we decided to study the relevancy of macrophage (M phi) activities to bone resorption. In this study, we investigated the phagocytic activity and activities of lysosomal enzymes of peritoneal resident M phi from rats fed a high-sucrose diet (Diet 2000) to appreciate the effects of Diet 2000 on systemic and local factors. Minkin et al. have postulated that bone-derived chemotactic factors were released from foci undergoing resorption. And so, we examined the effects of the supernatant from alveolar bone cultures (Bone-sup) prepared from rats fed Diet 2000 on the activities of glycogen induced peritoneal M phi. As a result we observed mild alveolar bone resorption with slight inflammation when the rats were fed Diet 2000 for six months. In the periodontal tissue, we found inflammatory cell infiltration, destruction of the periodontal ligament, and lacunae in the alveolar bone due to resorption. The phagocytic activity of M phi treated with Bone-sups was suppressed before the periodontal tissue, which is inflammatory condition such as alveolar bone resorption. Furthermore the phagocytic activity of resident M phi taken from rats on the Diet 2000 was suppressed. After one month of the Diet 2000, the activity of acid phosphatase (AcP), a lysosomal enzyme of M phi, was suppressed, but by six months it was enhanced. The activity of beta-N-acetyl-D-glucosaminidase (NAG), another lysosomal enzyme of M phi, was suppressed over the total period of Diet 2000 before the periodontal tissue was destroyed. These findings suggest that the capacity for defense against infection by M phi is suppressed when periodontitis is initiated by Diet 2000 feeding and that M phi activities are influenced by some factors elaborated by cells in the alveolar bone.

Alveolar Bone Loss↗
PubMed1989

Synchronization of amniotic fluid cells for high resolution cytogenetics.

A high resolution technique was applied to amniotic fluid cells by synchronization. After inoculation, the cells were incubated for 30 h in the presence of either thymidine or 5-bromodeoxyuridine (BrdU). After removal of the blocking agent and addition of a low concentration of thymidine, the cells were incubated for another 6 1/2 7 h, then harvested in prometaphase without colcemid. This technique gives a mitotic index of 3.7 per cent after thymidine synchronization and of 3.2 per cent after BrdU synchronization, and more than half of the mitoses were in the earlier phases with the chromosomes showing more than 550 bands per haploid set. GBG, GTG, and RHG prometaphases are presented. Precise high-resolution banding of chromosomes of amniotic fluid cells can increase diagnostic accuracy.

Amniotic Fluid↗