PubMed Health⌕ Search

Biomedical subjects

Y F Ai

Publications and source records attributed to Y F Ai.

9 recordsLinked to original sources
PubMed2001

[Reconstruction of tissue engineered vascular model in vitro].

OBJECTIVE: To explore the feasibility of reconstructing tissue engineered vessel in vitro. METHODS: Bovine endothelial cells were isolated from calf thoracic aorta by enzyme digestion methods and subcultured and purified. The endothelial cells of the 3rd to 7th passages were seeded into the inner surface of tubular scaffold material by polyglycolic acid(PGA) coated with cross-linked collagen, and cultured in vitro for 10 days using dynamic rotation culture technique. Scanning electron microscopy was used to analyse the morphological characteristics, and prostacyclin released by endothelial cells was measured by radioimmunoassay of 6-keto-prostaglandin F1 alpha. RESULTS: The VIII factor staining of cultured endothelial cells was positive. The endothelial cells adhered well on the inner surface of tubular scaffold material with confluent monolayer covering(91.2 +/- 1.5)%. The endothelialized model released prostacyclin at a rate of (4.6 +/- 0.5) micrograms/cm2.min. There was significant difference to control group (P < 0.05). CONCLUSION: The PGA coating with collagen is an ideal scaffold for endothelial cells, the coverage rate is increased through dynamic rotation culture technique. It will lay a good foundation for architecture of a laminated structure of tissue engineered vessel.

Animals↗
PubMed2001

[Expression of endogenic bone morphogenetic protein in repairing rabbit skull with tissue engineering technique].

OBJECTIVE: To explore the distribution and effect of endogenic bone morphogenetic protein (BMP) in repairing rabbit skull with tissue engineered bone. METHODS: The autologous osteoblast-like cells were instantly implanted onto polyglycolic acid (PGA) matrix coated with collagen. The rabbit skull defect models were established by resection of bilateral 1.5 cm x 1.0 cm full-thickness parietal bone in 18 New Zealand rabbits, which were randomly divided into two groups. In one group, the composite of osteoblast- like cells and PGA matrix were grafted into the defect on one side of the skull as experimental group I, leaving the same defect area on the other side as control group without any graft implanted. In the other group, simply PGA was done in the same way as experimental group II. The tissue samples were harvested at 3, 8 and 14 days postoperatively and examined by histological and immunohistochemistry methods. The concentrations of BMP in different regions of the samples were measured using computer image analysis system. RESULTS: After 3 days of operation, the BMP positive cells were found in the matrix of experimental group I. At 8 days postoperatively, the formation of new bone on experimental group I was prior to that of experimental group II and control group. On the 14th day, bone trabecula was formed on the experimental group I, but there was only fibrous tissue on control group. The concentration of BMP on the experimental group I and II were higher than that of corresponding region on control side. CONCLUSION: The osteoblast-like cells instantly implanted onto PGA matrix can synthesize and secrete BMP. It may be one of the reasons of tissue engineered bone inducing new bone regeneration that localizing endogenic BMP in bone defect area, increasing the concentration of endogenic BMP and improving its distribution by tissue engineering technique.

Animals↗
PubMed2000

[Application of multiple tissue expanders for repair of facial and neck scar].

OBJECTIVE: To repair facial and neck scar using tissue expanding technique. METHODS: From January 1991 to January 1995, 16 cases with facial and neck scar were treated. Multiple tissue expanders were put under the normal skin of facial and neck area, after being fully expanded, the scars were excised and the expended skin flaps were transplanted to cover the defects. The size and number of tissue expanders were dependent on the location of the scars. Normally, 5 to 6 ml expanding volume was needed to repair 1 cm2 facial and neck defect. The incisions should be chosen along the cleavage lines or in the inconspicuous area, such as the nasolabial fold or submandibular region. The design of flap was different in the face and in the neck. In the face, direct advanced flap was most common used, whereas in the neck, transposition flap was often used. Appropriate tension was needed to achieve smooth and cosmetic effect. It was compared the advantages and disadvantages of several methods for repair of the defect after facial and neck scar excision. RESULTS: Fifteen cases had no secondary deformity after scar excision. Among them, 1 case showed blood circulation disturbance and cured through dressing change. Ten cases were followed up and showed better color and texture in the flap, and satisfactory appearances. CONCLUSION: Tissue expanding technique is the best method for the repair of facial and neck scar, whenever there is enough expandable normal skin.

Adolescent↗
PubMed1994

[Haemolytic transfusion reaction of surgical patients due to incompatibility of Rh blood groups].

Haemolytic transfusion reactions occurred in 4 patients under plastic surgery due to incompatibility of Rh blood groups. The reaction in one of the patient occurred not only abrupt but severe and finally died of renal failure. Other three patients with delayed haemolytic reactions survived after treatment. Since more than 99.5% Chinese population is Rh positive, cross-matching on Rh blood groups is not a routine. The reactions develop usually different from typical ABO blood group haemolytic reactions and are not easy to make an early diagnose. If the surgical patients show profound anemia and haemorrhage following transfusion which could not be explained by bleeding and coagulation abnormalities, haemolytic transfusion reactions due to incompatibility of Rh blood groups might be considered.

Adult↗
PubMed1989

[Planning of a local flap of expanded scalp for repair of alopecia cicatrisata].

Tissue expansion of scalp opens a new way for the treatment of alopecia cicatrisata. From May 1986 to April 1988, 56 cases of alopecia cicatrisata and skull outcrop had been repaired by Chinese tissue expander in our department. All cases got good results. Of them, the area of alopecia was over 120 cm2 and the greatest one (320 cm2) consisting of two third of the total scalp in 21 cases. There were 49 cases repaired by one expansion and other 7 cases followed by a secondary expansion. The characteristics of the expanded scalp and the common types of local flap design had been discussed. It was applicable for all kinds of alopecia cicatrisata and both for children (over 3 yrs) and adults. The results of scalp expansion in children revealed superior than that in adults. We considered that the repairing of alopecia cicatrisata by scalp expansion had more advantages than other methods.

Adolescent↗