Establishment of a rat osteoporotic model by ovariectomy combined with glucocorticoid exposure / 中国组织工程研究

BACKGROUND:There are many postmenopausal women taking hormone, which leads to much loss of bone mass, further inducing fragility fractures. The studies on the hormone exposure combined with ovariectomy-induced osteoporotic model are still immature, and the related molecular mechanism remains unclear. OBJECTIVE: To establish the rat osteoporotic model induced by ovariectomy combined with glucocorticoid exposure and to explore the underlying molecular mechanism. METHODS: Thirty 3-month-old female Sprague-Dawley rats were randomly divided into blank control, sham and model groups (n=10 per group). The rats in the blank control group received no intervention; rats in the sham group were clipped off a little of coeliac adipose tissue; the model rats received bilateral ovariectomy and 4-week administration of glucocorticoid. RESULTS AND CONCLUSION:At 4 weeks after modeling, compared with blank control and sham groups, the model group showed significantly lower bone mineral density of the femur, number of bone trabeculae and bone volume/total volume, and significantly wider bone trabecular spacing. Additionally, the model group revealed the damaged bone trabecular structure and thiner cortical bone. The expression level of Runx2 was downregulated whereas both collagen type 1α1 and peroxisome proliferators activated receptor γ mRNA were upregulated in the model group. These findings suggest that ovariectomized rats exposed to glucocorticoid rapidly develop femur osteoporosis, maybe by downregulating the expression of Runx2, as well as upregualting collagen type 1α1 and peroxisome proliferators activatedreceptor γ mRNA.

Augmentation rhinoplasty using a reverse alar cartilage flap assisted with implantation of silicon prosthesis / 中华医学美学美容杂志

Objective To investigate a new method which could not only avoid the extrusion of the silicon implant, but also be benefit for the reconstruction of nasal tip and alar during nasal augmen-tation procedure. Methods Folded lower lateral cartilage flap combined with silicon implant was ap-plied for nasal dorsal augmentation and reconstruction of nasal tip and alar with its unique character at the same time. Results 12 cases were all primary healing, without infection, extrusion of implant and other complications. One month after operation, the projection of nasal tip was increased, which had better delicate and definite shape, natural appearing tip adding contour and height to nasal tip, pleas-ant definition. Conclusions Folded lower lateral cartilage flap combined with silicon implant is an ef-fective method to decrease the incidence of extrusion, when we want to have a little over-projected na-sal tip with prosthesis. It is also helpful for reconstructing the nasal tip and alar with its unique char-acter.

Experimental study on the toxic effects of hydrophilic polyacrylamide gel / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the safety of Hydrophilic polyacrylamide gel (HPAG) through an animal experiment.</p><p><b>METHODS</b>After HPAG was injected underneath the skin of SD rats, tissue specimens were taken for general and histological examinations. The cytotoxicity was evaluated by agar coverage and MTT method.</p><p><b>RESULTS</b>It was determined that the cytotoxicity was over level-two. The toxicity to kidney was obvious. The local histological reaction was slight and a thin fibrous membrane was formed around HPAG, which became stiff gradually. The shape and location of the injected HPAG was not stable. The HPAG could not be drawn out completely.</p><p><b>CONCLUSION</b>HPAG has obvious cytotoxicity and is not a suitable material as soft tissue implant for the bad shape and texture.</p>

Repeated tissue expansion in head and neck / 中华医学美学美容杂志

Objective To summarize the experiences in treating 30 cases of skin soft tissue defects in head and neck by applying repeated expansion, and to explore an effective and satisfactory method of massive defect repair in head and neck. Methods Skin soft tissues were repeatedly expanded for 1 to 3 times after the first expansion. Massive skin defects in head and neck were repaired several times by useing repeated expansion of flap. The size of the skin defects ranged from 29cm?24cm to 10cm?8cm. The indications, complications and experiences in the treatment were discussed. Results A total of 30 cases were treated. Complication incidences of every expansive procedure were 27%, 15%, 14% and 0% respectively . After 6～12 months postoperative follow-up, the appearance and functional restoration was satisfactory. Conclusion Repeated expansion is an excellent method of repairing massive defects in head and neck.