Effect of Mesenchymal Stem Cells and Platelet-Derived Growth Factor on the Healing of Radiation Induced Ulcer in Rats

Radiation-induced skin ulceration is a frequent complication of radiation therapy. This study investigated the effects of rat mesenchymal stem cells (rMSCs) and platelet-derived growth factor (PDGF) on the healing of radiation-induced soft tissue injury. Sprague-Dawley rats (n=17) were irradiated on the right and left buttocks with a single dose of 50 Gy. The right buttocks were administered with phosphate-buffered solution as a control. The left buttocks were administered with either rMSCs (2×10⁶ cells), PDGF (8 µg), or PDGF combined with rMSCs. Administration was done at three weeks after irradiation. Wound healing was analyzed by calculating the percentage of residual ulcerated skin area compared to the total irradiated area during the five week healing period after administration. Modified skin scores were also assessed. Finally, skin lesions were histologically evaluated. More than 40% of the irradiated skin area within the irradiated zone underwent ulceration within 16 days postirradiation, with peak ulceration exceeding 50% around three weeks post-irradiation. Administration of rMSCs or PDGF alone did not confer any significant healing effect. The combined rMSCs+PDGF treatment significantly reduced the wound size compared with the nontreated control up to two weeks postinjection. Regarding the histological examination, lesions administered with PDGF (either alone or mixed with rMSCs) resulted in a greater deposition of highly organized collagen fibers throughout the dermis layer, compared with the control. In conclusion, the combined administration of rMSCs and PDGF efficiently enhanced the healing of radiation-induced skin ulceration.

A study about early osteoconductivity of porous alloplastic carbonapatite and anorganic bovine xenograft in canine maixlliary augmentation model

Lemierre syndrome: A case report

Abscesses are common in the oral and maxillofacial area. However, secondary thrombosis of the internal jugular vein accompanying the primary abscess is rare. In 1936, Andre Lemeierre studied 20 patients who showed an initial oropharyngeal infection, septicemia, internal jugular vein thrombosis, and secondary spread of the infection, and after then this condition Lemierre syndrome. Clinically, these patients present with tonsilitis lasting several days, continuous fever, and cervical pain. In the past, ligation and excision of the internal jugular vein was often performed. Current therapeutic modality for this condition is appropriate antibiotic prescription and surgical drainage of abscess. This case report presents a patient who showed symptoms of Lemierre syndrome, initiated as an oropharyngeal infection then developed thrombosis of the internal jugular vein. This patient was admitted into Seoul National University Dental Hospital. In addition to routine antibiotic therapy, surgical incision and drainage of the infection site was performed. Without ligation or excision, the thrombosed IJV disappeared eventually. As the Lemierre syndrome is not a common disease, this case report and review of the literature would be useful regarding a treatment of patients with Lemierre syndrome.