Biological Characterization of Marssonina coronaria Associated with Apple Blotch Disease

Marssonina coronaria associated with apple blotch disease causes severe premature defoliation, and is widely distributed in Korea. Thirteen isolates were collected from orchards located in Gyeongbuk Province from 2005~2007. All isolates displayed over 99.6% and 99.2% sequence similarity to each other in internal transcribed spacer regions and partial sequences of 28S rDNA, respectively. The isolates were phylogenetically closely related to Chinese isolates. Selected isolates did not differ in their pathogenicity. The optimum conditions for fungal growth were 20degrees C and pH 6 on peptone potato dextrose agar (PPDA). Peptone and mannose were the best nitrogen and carbon source, respectively. Fungal growth was better on PPDA than on common potato dextrose agar. This study provides valuable information for integrated disease management program and facilitates the routine culturing of M. coronaria.

Magnetic Resonance Imaging on Posterior Cruciate Ligament Injury: Can the PCL hea

PURPOSE: The aim of this study was to elucidate the continiuty of ligament in chronic injury of the pos- terior cruciate ligament(PCL). MATERIALS AND METHODS: Magnetic resonance imaging(MRI#) of twenty-six PCL injury patients with grade II or III laxity and more than 5mm side to side difference on stress radiographs were reviewed in terms of ligamentous continuity and thickness of the ligament at average 7.2 months(range:1-36) after injury. RESULTS: Eighteen PCLs(69%) showed continuity of PCL. When thickness of the ligament in cases without continuity was rated as zero, the average thickness of the PCLs as compared to intact portion of the ligament increased as the time from injury elapsed; 16.4% in 0 2 months group(7 cases), 30.0% in 3- 5 months group(6 cases), 53.8% in 6-8 months group(9 cases) and 80.0% in over 9 months group(4 cases). CONCLUSTION: More than two thirds of PCLs in symptomatic chronic injury showed ligamentous continuity on MRI. The longer the interval from injury was, the thicker the PCL was.

Morphological and Biochemical Changes of Transitional Zone after Achilles Tendon-bone Autogenous and Allogeneic Graftin Rabbitis Achilles Tendon-bone Autogeous and Allogeneic Graft in Rabbits / 대한정형외과연구학회지

Allografts or autografts of bone-tendon unit have been used for ligament injuries or deficiencies after limb salvage operation for malignant bone tumors around joints. While the remodeling process of the ligament or tendon of the allograftor autograft and the microscopic and biomechanical changes of tendon-bone graft interface have been widely investigated, little is known about the ultrastructural and biochemical changes of the transitionall zone in tendon-bone junction. This study was performed to analyzed the ultrastructural and biochemical changes of the transitional zone after tendon-bone auto-and allo-grafting. A total of twenty four rabbits were divided into two group. In 12 animals(allograft group), two Achilles ten-don-bone unit per each animal were taken and transplanted to another rabbit after preservation below -70degrees C for 2 weeks. In the other 12 animals(autograft group), the Achilles tendon-bone unit was harvested from one side and transplanted to the other side of the rabbit. After operation, their legs were immobilized with short leg cast for 4 weeks, and then mobilized freely. Four animals in each group were sacrificed at four, eight and sixteen-weeks after the transplantation, and their grafted Achilles tendon-bone interfaces were used for analysis of the ultrasturctural and biochemical changes. The following results were obtained. 1. Histologically new cartilage cells were observed at postoperative 16 weeks with local presence of faint tidemark in the autograft group but not in the allograft group. Complete remodeling of the transitional zone had not observed histologically in both groups. 2. Ultrasturctural analysis revealed no definite differences between both groups. However, the slightly rapid appearance of parallelism and cross-striation of microfibrils in the autograft group and time-related restoration of fibers and fibroblasts were observed. 3. From biochemical analysis, type I collagen concentratin was increased, and an early rapid increase of type III collagen and glycosaminoglycan were also observed. In conclusion, these data suggested that type III collagen and glycosaminoglycan are important in stabilization of grafted tendon-bone unit, especially in the transitional zone. The histological and biochemical changes in allograft group were relatively similar to that of autograft group although the allograft group showed the delayed pattern of remodeling. Therefore, the tendon- allograft could be used as a good substitute for the autograft for tendon or ligament reconstruction when no suitable autograft is available.