Genotypic variation of Agrobacterium-mediated transformation of Italian ryegrass

In the present study, genotypic variation of Agrobacterium-mediated transformation of Korean Italian ryegrass has been evaluated. Mature seed-derived calli of seven cultivars were inoculated and co-cultured with Agrobacterium tumefaciens carrying the binary vector pCAMBIA1301, which contains a reporter gene (gus) and a plant selectable marker gene conferring resistance to hygromycin (hpt) in the T-DNA region. The effects of several factors such as callus type and callus age on transformation effectiveness and the expression of the GUS gene were investigated. The highest transformation effectiveness (6.7 percent) was obtained with the Hwasan 101 cultivar when 9-week-old calli (type-I) were inoculated with Agrobacterium. The overall transformation rates of the examined cultivars ranged from 0.4 percent to 6.7 percent. GUS histochemical assays, PCR, and southern analysis of transgenic plants demonstrated that transgenes were successfully integrated into the genome of Italian ryegrass. Thus, evaluation of transformation effectiveness and selection of a suitable cultivar of Italian ryegrass may improve molecular breeding of this species.

An Ectopic Pleomorphic Adenoma in the Superficial Subcutaneous Layer of the Preauricular Area

Pleomorphic adenoma is a benign tumor originated from the mature salivary tissue. Ectopic pleomorphic adenoma is defined as an unusual presentation of pleomphic adenoma in other sites except the major salivary gland and the minor salivary gland. Ectopic pleomorphic adenoma was found in the soft tissue of the neck, in the skin of the external auditory canal, in the subcutaneous layer of the nose, and in the lymph node of the mediastinum. Ectopic pleomphic adenoma could appear due to the metastasis, the neoplastic degeneration of the ectopic salivary tissue, or the implantation after the surgery of a salivary gland tumor. We present a case of pleomorphic adenoma found in the superficial subcutaneous layer above the superficial musculoaponeurotic system(SMAS) of the preauricular area. The patient had no history of the surgery of the salivary tumor and no specific physical finding. We discussed the previous cases of ectopic salivary tissues and ectopic pleomorphic adenomas. No case of the ectopic salivary tissue nor ectopic pleomorphic adenoma in the superficial subcutaneous layer of the preauricular area has been reported. This case could be a rare presentation of the ectopic pleomorphic adenoma from the ectopic salivary tissue arising from the division of the parotid gland in early embryonic period.

Surgical Treatment of Burn Induced Helical Keloid with Excision and Full-Thickness Skin Grafting

Burn induced helical keloid is usually manifested by the severe disfigurement. The satisfactory reconstruction of the helical rim has not been achieved by the methods such as full thickness skin grafting(FTSG), core extirpation, and simple excision combined with intralesional steroid injection. In treatment with FTSG, the frequent failure of skin graft in the helical rim is due to the lack of adequate vascular supply in the recipient bed and the exposed helical cartilage after keloid excision. However, if the recipient bed with rich vascularity is widen and sufficient to maintain the viability of the graft, FTSG is the best method that leaves less donor morbidity and is able to reconstruct the natural appearance of helix. We proposed that the improved survival of skin graft could be achieved by better vascular supply by the deepithelialization of the surrounding normal skin after keloid excision. Five helical burn keloids and hypertrophic scars were reconstructed by the method of excision and FTSG. There were no recurrence and the results showed good texture and similar skin color. Excision of scar and FTSG is a satisfactory method to treat helical burn keloid.