Culture of Chondrocytes on Scaffolds with Different Pore Network of PLGA and PLLA

This study was performed to investigate the in vitro proliferation and migration of rabbit auricular chondrocytes into the various sized pore of PLLA and PLGA scaffolds. The chondrocytes were harvested, expanded, and seeded onto PLGA(50 : 50, 75 : 25, 85 : 15) and PLLA scaffold having either small(50 - 100 micrometer) or large(300 - 350 micrometer) pores. On the 4th and 8th week after culture, histologic observation and quantitative DNA assay were done. We noted that the largest amount of DNA was found in the 85 : 15 PLGA sponges than others, and in the 4th and 8th week, some amount of DNA was detected in the lower portion of 85 : 15 PLGA sponge only, and DNA amounts were increased during the culture period in the 85 : 15 PLGA, significantly. We also found that the numbers of cells were low in middle portion of scaffolds, and in large pore-sized group of 85 : 15 PLGA, there were many cells in the lower portion of the scaffolds more than that of small pore group. In conclusion, the pore size of the scaffold for chondrocyte culture is important for cell migration and proliferation, and PLGA, especially 85 : 15 PLGA with 300- 350 micrometer sized pore is the more suitable biomatrix for proliferation and migration of the chondrocytes.

Complications after Open Reduction of Blow-out Fracture using Silicone Sheet

Many kinds of alloplastic implants have been used for surgical reconstruction of orbital wall fractures. Although complication rates caused by them are known to be higher than that by autologous grafts such as calvarian bone graft, there are few reports about collective cases for individual alloplastic implants. A retrospective review was performed on 115 patients who underwent orbital blow-out fractures reconstruction with silicone sheet(Silastic(R)) implants between 1989 and 1998. After the follow-up period from 1 month to 5 years, six patients(4.3%) had to undergo reoperations for implant removal because of complications such as infection, hematoma, displacement and extrusion of implant. Symptoms of Silicone sheet complications were progressive periorbital swelling, tenderness, proptosis, hypesthesia and persistant diplopia. Complications were diagnosed by history of Silicone sheet insertion, physical examination and follow-up facial bone or orbit CT. Mean duration of onset was 23.3 months. In all cases of complication, implants were surgically removed and proper antibiotics were used postoperatively. The symptoms subsided immediately without any other sequelae. The reconstruction of blow-out fractures with silicone rubber implant may cause serious late complications such as infection, displacement, hematoma, migration and extrusion. Therefore, careful follow up is nesessary, and prompt sheet removal should be considered first, if such complications are confirmed.

The Effect of Glucose Control on DNA and Collagen Synthesis of Cultured Fibroblasts of Chronic Diabetic Wounds

Diabetes is accompanied by delayed wound healing and insufficient granulation tissue formation, possibly because of a defect in fibroblast function. Maintaining glucose level at acceptable low level is considered to be an important part of the clinical treatment of diabetes, but the exact mechanism by which diabetes delays wound repair is not yet known. This study was designed to evaluate the effects of glucose on proliferation([3H]-thymidine uptake) and collagen synthesis([3H]-proline uptake) in dermal fibroblasts from non-lesional skins and chronic wounds. The subjects were divided into 3 groups: non-diabetic control(n = 5), glucose controlled(glycated Hb 8%) diabetics(n = 5). The fibroblasts were cultured in two conditions, low glucose(5 mM) and high glucose(20 mM) medium. The data were compared using Mann-Whitney test. The results are as follows: 1. There were no significant differences in the proliferation and collagen synthesis of non-lesional skin fibroblasts in all groups. 2. In high glucose medium culture, the proliferation of the fibroblasts from the wound of the glucose uncontrolled diabetic group was significantly lower than those of the other 2 groups(p< 0.05), and the collagen synthesis of the wound fibroblasts of the control group was significantly higher than those of 2 diabetic groups(p< 0.05). 3. The proliferation and collagen synthesis of the wound fibroblasts in all groups were significantly lower than those of the non-lesional skin fibroblasts(p< 0.05). 4. In the control group and the glucose controlled diabetic group, the proliferation of the wound fibroblasts in the high glucose culture media were lower than those in the low glucose culture media(p< 0.05). Also, in the glucose controlled diabetic group, the collagen synthesis of the wound fibroblasts in the high glucose culture medium was lower than that in the low glucose culture medium(p< 0.05). These results demonstrate that the glucose level may affect the proliferation and collagen synthesis of fibroblasts, and the strict blood glucose control is beneficial to the prevention and treatment of diabetic chronic wounds.

A Case of Small Cell Neuroendocrine Carcinoma in the Parotid and Lacrimal Glands

Small cell carcinoma is most frequently found in the lung. Extrapulmonary sites of this neoplasm account for only 4% of all small cell carcinomas. Small cell carcinomas arising in the salivary glands are extremely rare, accounting for less than 1% of all parotid gland carcinomas. A 72-years- old women visited our clinic to evaluate hard protruding masses in the left preauricular region and the left orbit. Superficial parotidectomy and incisional biopsy for orbital mass revealed small cell neuroendocrine carcinoma. As the extrapulmonary small cell neuroendocrine carcinoma, arising in both left parotid and lacrimal glands is reported rarely in the world and not reported in Korea yet, we report its clinical progress.

A Case of Malignant Clear Cell Hidradenoma

Malignant clear cell hidradenoma is a rare eccrine gland malignancy characterized by a solitary nodule on the head, trunk or distal extremity. We report a case of malignant clear cell hidradenoma in the left sole of a 66 year old female patient. Despite wide resection, regional lymph node dissection and radiation therapy, wide spread regional invasion and multiple distant metastasis were developed. As the malignant clear cell hidradenoma is reported rarely in the world and not yet reported in Korea, we report its clinical process of the diagnosis and treatment to patient's death.

Delay Effect of PGE1 on Rat Transverse Rectus Abdominis Musculocutaneous Flap

This study was designed to find an effective delay method for preventing the ischemic compromise of TRAM flap in rat. Forty Sprague-Dawley rats were divided into 4 groups evenly and a left inferior epigastric vessel pedicled TRAM flap, sized 5.0 x 3.5 cm was created on the upper abdomen. Experimental groups included group 1(control): no delay procedure before elevation of flap, group 2(surgical delay): the left superior epigastric vessels and the contralateral rectus perforators were ligated 2 weeks before elevation of flap, group 3(pharmacological delay): prostaglandin E>(0.5 microgram) was given intraperitoneally for 2 weeks before elevation of flap daily, group 4(surgical and pharmacological delay): the same surgical and pharmacological delay have been done simultaneously. On the seventh day after operation, we evaluated and compared the results by the measurement of the flap survival area, the observation of the vessel distribution through Microfil casts and the measurement of vessel surface area through histologic slides. The results were as follows; 1) The mean percentages of the flap survival area of group 2(73.32+/-21.07%), 3(71.77+/-l 17.49%) and 4(89.54 +/-11.38%) were higher than that of group 1(41.23 +/- 14.26%) significantly(p < 0.05). 2) The vessel distributions of group 2, 3 and 4 were much abundant than that of group 1 in Microfil casts. 3) The vessel surface areas of group 2, 3 and 4 were higher than that of group 1 significantly(p < 0.01) and that of group 4 was higher than that of group 2(p < 0.05). In conclusion, prostaglandin E could be used to increase the flap survival area in rat TRAM flap model as a pharmacological delay and the effect of prostaglandin E was comparable to that of the surgical delay.

Treatment of Malignant Eccrine Spiradenoma

Malignant eccrine spiradenoma is very rare neoplasm of cutaneous adnexal origin, arising from previously benign eccrine spiradenoma. We present an additional case of malignant eccrine spiradenoma in abdomen of 56-year-old female patient. The mass was stable for 25 years and recently increased in size and became strikingly painful and tender. The excised mass showed typical findings of eccrine spiradenoma 8 its malignancy. There was no evidence of local invasion & distant metastasis. We resected the tumor mass with 3 cm safty margin and have followed up the patient.

A New Animal Model of Proliferative Scarring

Proliferative scarring in the form of keloids and hypertrophic scars continues to be a clinical problem for some patients. The lack of an animal model for such scarring has been an obstacle to studying the biology and effective therapy of these entities. Consequently we created an accurate reproductive animal model to systematically study them. Human proliferative scars were explanted into flaps based on isolated vascular pedicles in congenitally rats. We compared the procollagen type III peptide levels of proliferative scar tissue before and after explanting. The procollagen type III peptide levels of explanted proliferative scar tissue remained increased as before explanting. Histological analysis of the explanted proliferative scar tissue revealed that all explants retained their original histotypic character even after 1 year. We could also retain the volume of implanted proliferative scar for 1 year and studied in vitro cellular proliferation. Fibroblast cultures from explanted scars demonstrated less aggressive growth characteristic than those from original surgical specimens. The advantages of this animal model are as follows: 1. The explants retain their histotypical character for a long period. 2. Placement of the explants outside the dorsum of a nude rat makes serial observation and measurement easier. 3. Agents under test can be injected into the explants through a catheter inserted into a single pedicle of island flap without the possibility of spreading systematically.

Cranial Fasciitis: Presentation as a Temporal Mass

Cranial fasciitis is a rare morphological variant of nodular fasciitis. It is characterized by a rapid growing fibroblastic proliferative lesion that develops chiefly in childhood. It has varying size and involves the soft tissues of the scalp and the underlying skull. Accurate diagnosis and surgical excision is the key to management. Prognosis is good with rare recurrence. We report a case of cranial fasciitis in the temporal fossa of a 20-month-old girl and present a review of the literature.

The Response of diabetic Rabbit Femoral Artey on the Electrical Stimulation and vasodilators

This experiment was aimed to investigate the contractile responses of the fermoral artery to the electrical stimulation and the inhibitory effects of verapamil and papaverine on the electrical stimulation of the fermoral artery in the control (n=46) and the diabetic rabbits(n=40). Diabetic rabbits were made by and administration of alloxan (100 mg/kg) intravenously and sacrified 8 weeks later. Femoral arterial rings 3 mm in length were taken and mounted on the force-displacement transducer for the measurements of isometric tension. All experiments were done in the aerated (95% O2 with 5% CO2)biological chamber filled with Kreb's solution and the initial tension of 1.5g was applied to the rings. After 1 hour of equilibrium of the rings, the contractile responses of the electrical stimulation on the femoral arterial rings were taken without vasoactive drugs and then, under verapamil and papaverine solution. And we compared the morphologic findings of the vessels in the two groups in relation to the functional changes by transmission electron miroscopy. The results are as follows: 1. The contractile responses in the presence of verapamil or papaverine solutions to the electrical stimulation were lowed significantly in the fermoral arterial rings of the diabetic rabbits compared with that of the control rabbits (verapamil; 10M~10M: p<0.01, papaverine; 10M & 10M: p<0.01). 2. Transmission electron microphotographs showed many morphological differences of the femoral arteries between the control and the diabetic rabbits. These were irregularities of the internal elastic lamina and the hypertrophy of the cytoplasms of the smooth muscle cells. And also, there were many vacuoles in the cytoplasm of the endothelial cells, lateral to the internal elastic laminaes, and between the smooth muscle cells in the diabetic rabbit femoral artery. By this study, we found that the contractile responses of the femoral arterial rings to the electrical stimulation were decreased in the diabetic rabbits, and the vasodiatory effects of verapamil and papaverine on the electrically stimulated femoral arterial rings were also lowered in the diabetic rabbits compared with the control rabbits. These changes of the vasular responses of the diabetic vessel may be associated with morphological changes manifested by transmission electron microscopy or any other functional derangement of the vessels.

Bone infection associated with pressure sores: a clinical study

Pressure sores are common complications in patients with spinal injuries or cerebrovascular accidents. The management of pressure sores requires prolonged hospitalization and repeated surgical interventions with a high recurrence rate. Particularly osteomyelitis following initial pressure sores persistently complicates wound healing and recovery. Furthermore, it may also ultimately result in serious sepsis; thus an early diagnosis of osteomyelitis in pressure sore patients is crucial along with appropriate surgical and antibiotic therapy. Although many diagnostic methods were reported, there is no single 'gold' standard for early diagnosis of pressure sore-associated osteomyelitis. Authors reviewed pre-operative CBC, plain X-ray, Tc-99m bone scan, and post-operative biopsy results in 37 patients who had received surgical treatment for pressure sores in a 5-year period from September 1991 to August 1996. Based on these reviews, authors compared and analyzed the sensitivity and specificity in diagnosing osteomyelitis.The results were as follows: 1. Of 37 patients studied, 25 cases were confirmed histologically as osteomyelitis. Ischial region revealed the highest incidence of pressure sore-related osteomyelitis(78%, 14 out of 18 cases) while the regional incidence was as following in descending order : ischial, sacral, and greater trochanteric area. 2. Tc-99m bone scan had superior sensitivity(100%) and specificity(83%) to other pre-operative studies in diagnosing osteomyelitis.In conclusion, authors suggest that Tc-99m bone scan is the best diagnostic method because of its high sensitivity and specificity if osteomyelitis is clinically suspected in pressure sore patients. And in case the test result is positive, agressive surgical bone resection and appropriate antibiotic therapy based on bacterial culture from deep bone specimen should be combined to prevent complications or recurrences.

Surgical treatment of livedo vasculitis

Livedo vasculitis is thought to be a thrombogenic disorder that is related to the autoimmune disease. It clinically shows purplish mottling and recurrent painful ulcers in the lower extremities, leaving atrophie blanche after healing of the ulcers. Histopathologic finding are thrombotic occlusion in the mid-dermal vessels without necrotizing vasculitis. The therapeutic approach has largely been made by the use of drugs that stimulate endogenous fibrinolytic activitiy, that inhibit thrombus formation, or that cause vasodilation, but surgical intervention by excision and skin graftion has rarely been reported as a primary treatment.In our experience, two patients with livedo vasculitis, who had been unresponsive to various medications, were treated with wide excision and several times of skin grafting. And they experienced complete healing without recurrence.

Lacrimal canalicular reconstruction with various materials

This retrospective clinical study consists of 27 patients with lacrimal canalicular injury caused by various accidents and which were reconstructed with various materials in the department of plastic surgery at Catholic University Medical College from December 1987 to July 1996. These 27 patients were followed up at least 6 months after the canalicular reconstruction and their medical records were reviewed and analysed retrospectively in order to obtain the clinical pattern and understand the therapeutic results. The statistical items were the age and sex distribution, the causes of injury, the prevalent site of injury, the reconstruction materials, the duration of intubation and the results of treatment. The following results are obtained: 1. Males were more dominant than females by 4.4 : 1. 2. The patient age was from 6 to 73 years old and the prevalent age groups were the third and fourth decades(55.5%). 3. The most common cause of canalicular injury was the violence(29.6%) and was followed by traffic accident. 4. The left canaliculi, especially inferior canaliculi, was the prevalent injury site. 5. Regardless of the materials(P.V.C. tube, nylon and silicone tube) used in canalicular reconstruction, the longer duration of intubation was obtained the better result of treatment. 6. So the silicone tube with stainless steel(C-line canaliculus intubation set) was relatively inert and less complicating, it could be maintained more longer and had better results than other materials such as P.V.C. tube and nylon.

Numerical aberrations of chromosome 17 and her2/neu gene amplification, her2/neu and p 53 protein expression in breast cancer

Breast cancer is one of the leading causes of death attributable to cancer in women. In view of the limitations of conventional predictable factors of the breast cancer, additional second-generation parameters would be valuable in selecting the patients who would be most likely to be beneficial from adjuvant therapy and breast reconstruction. The author investigated the HER2/neu gene amplification and the number of chromosome 17 in 39 cases of paraffin embedded breast cancer tissues, 20 cases without lymph node metastasis and 19 cases with lymph node metastasis, using fluorescent in situ hybridization(FISH) and compared the results with HER2/neu and p 53 protein expression detected by immunohistochemical method. Eleven cases fibroadenoma were used as benign tumor control. Numerical aberrations of chromosome 17 were found in 17 out 39 breast cancer cases (44%)(monosomy in 10 cases, 26%; trisomy in 3 cases, 8%; tetrasomy in 3 cases, 8%; polysomy in 1 case ,3%), and the frequency of each type aberration was not significantly different between the negative and positive groups in lymph node metastasis. Monosomy of chromosome 17 was found in 2 out of 11(12%) fibroadenoma cases. HER2/neu gene amplification was found in 8 out of 39 cases (19%) and other 2 cases revealed HER2/neu gene amplification in lymph node metastatic tumor only, not in original tumor. Fourteen out of 19 cases of breast cancer with lymph metastasis showed HER2/neu protein expression both in original and metastatic tumors. All of the six cases showing HER2/neu gene amplification in original and/or metastatic tumor revealed HER2/neu protein expression. The frequency of HER2/neu gene amplification in the 39 breast cancer cases was not different between metastatic and non-metastatic groups(p= 0.284). However, HER2/neu protein expression was increased significantly in the metastatic group(p=0.028). None of the 11 fibroadenoma cases revealed HER2/neu gene amplification or HER2/ neu protein expression. Nine out of 19 cases of breast cancer with lymph node metastasis showed p 53 protein accumulation in original tumor(47%), but 3 of them revealed p 53 protein accumulation only in original tumor. The frequency of p 53 protein accumulation was not significantly different between metastatic and non-metastatic groups. None of the 11 fibroadenoma cases revealed p 53 protein accumulation. In conclusion, there are no differences between the lymph node metastatic group and non-metastatic groups in numerical aberrations of the chromosome 17 , amplification of the HER2/neu gene expression and accumulation of the p 53 protein in breast cancer. However, the HER2/neu protein expression was increased significantly in lymph node metastatic group, so it could be one of the predictors of the metastasis in breast cancer.

Effects of topical applications of epidermal growth factor on wound healing of uve-irradiated rat

Chrionic exposure of the skin UVB radiation causes erythema and dermal connective tissue damage including wrinkling, neoplastic skin lesions, and delayed wound healing. The topical application of epidermal growth factor(EGF) has been reported to be effective in the treatment of partial and full thickness skin wounds, second degree burns, incision wound, and chronic ulcers. However, its effect thickness UVB damaged skin has not yet been defined. Fifty Sprague-Dawley rats were divided into four groups: UV irradiated-EGF treated group; UV irradiated-EGF untreated group; UV nonirradiated-EGF treated group; UV nonirradiated-EGF untreated Group peroperatively, the UV exposure groups were irradiated with UVB (40 mJ/cm2, 2 MEDs) on the dorsal skin every other day for 12 weeks. Following cessation of UNB exposure, a standard 6 cm midline dorsal linear incision was made in each animal. The animals in EGF treated group were topically applicated with EGF ointment (10 microgramg/g) twice a day. Wounds were excised and wound burst strength was applicated using tensiometer on the 7th and 10th postwounding days. The wound burst strength of the UV irradiated-EGF treated group (662+/-49.7 g/cm) was significantly increased compared to that of the UV irradiated-EGF untreated group (352 +/-40.3 g/cm) (p < 0.01) and even stronger than that of the UV nonirradiated-EGF untreated group (570+/-44.7 g/cm) (p < 0.05). On the 10th day, there was no significant difference in the wound burst strength between the UV irradiated-EGF treated group (1248 +/-101.3 g/ cm) and UV nonirradiated-EGF treated group (1270+/-98.5 g/cm) (p = 0.595). Histological examination revealed epidermal hyperplasia, degeneration of collagen fibers, and inflammatory cell infiltration in the UV irradiated groups. Thick epidermis, prominent skin appendages, increased capillaries and fibroblasts, and linear organization of collagen fibers were observed in EGF treated groups. These results indicate that repeated exposure to UVB irradiation alters normal skin structure and adversely affects subsequent wound healing and the topical application of epidermal growth factor facilitates wound healing of UVB damaged skin.

Retrospective study on the local redurrence and distant metastasis of malignant skin tumors

The results of a retrospective study on 197 cases of malignant skin tumors, which were operated from July 1991 to June 1996 were presented. 1. Primary malignant skin tumors in our series included basal cell carcinoma (42%), squamous cell carcinoma (39%), melanoma (7%). Eighty five percentage of them were developed after 5th decade. There was a slight male preponderance (male to female ratio; 1.2:1). 2. seventy five percentage of malignant skin tumors were occurred in the head and neck. However 34% of squamous cell carcinoma occurred in the extremities. 3. Overall recurrence rate was 7.1% and overall metastasis rate was 7.6%. Seven cases (8.5%) of basal cell carcinoma were recurred without metastasis and seven cases (53.8%) of melanoma were meatastasized without recurrence. 4. Overall recurrence occurred at average 27 months after primary resection and 79% of them occurred in the head and neck. Among 14 recurred tumors, one recurred secondarily and three were metastasized elsewhere. 5.Two thirds of metastasis occurred within one year of resection. Mortality rate in the patients with metastasis was 40%. Metastases involved multiple organs and involved lymph nodes most frequently. 6.Fifteen patients with metastasis were treated with surgery alone (2 cases), surgery and adjuvant therapy (3 cases), radiation and/or chemolherapy without surgery (6 cases), and no therapy(4 cases).

Prevention of reperfusion injury with CD18 monoclonal antibody and superoxide dismutase

Prolonged ischemia results in cellular necrosis and only prompt restoration of blood flow will prevent this type of injury. However, reperfusion itself can cause significant injury of previously ischemic tissue, i.e. "reperfusion injury'. This is an issue of concern in many areas of reconstructive surgery including free tissue transfer and replantation. Many factors have been implicated in the cause of reperfusion injury. Oxygen free radicals have enjoyed increasing popularity recently, but leukocytes had been thought to have a role only in the healing process that follows ischemic injury. Current studies in myocardium, liver and intestine have shown a dramatic increase in tissue leukocytes after ischemia-reperfusion and evidence implicating leukocytes in pathogenesis of ischemia-reperfusion injury has come from studies demonstrating significant injury reduction by depletion of circulating neutrophils. Therefore, increased neutrophil adhesiveness is a critical early step in the sequence of events leading to neutrophil-mediated injury. The purpose of this study is to evaluate the effect of CDl8 monoclonal antibody(CDl8 mAb), blocking antibody of neutrophil adherence, and superoxide dismutase (SOD), free radical scavenger, on reperfusion injury in rat epigastric island skin flap. The epigastric pedicle was occluded for six hours with ambient temperature at 22+/-1degrees C. The epigastric nerve was carefully dissected out and left intact to minimize autocannibalization. The flaps were sutured back down to their beds over interposed silicone sheets to prevent plasmatic imbibition. Fifteen minutes before reperfusion, the flaps were perfused with saline, CDl8 mAb(1 mg/kg), SOD(20,000 unit/kg) or CDl8 mAh/SOD(1 mg/kg + 20,000unit/kg). Percentage of flap survival was assessed by computerized planimetry on the seventh day. Tissue biopsies for myeloperoxidase(MPO) and malonyldialdehyde (MDA) were obtained at 24 hours after reperfusion. The results were as follows. 1. Percentage of flap survival was significantly increased in CDl8 mAb/SOD, CDl8 mAb and SOD groups in order, compared to the control(P < 0.05). Percentage of flap survival was significantly increased in CDl8 mAb group as compared with SOD group(p < 0.05). Percentage of flap survival significantly increased in CDl8 mAb/SOD group as compared with CDl8 mAb and SOD groups(p < 0.05) 2. MPO activity was significantly decreased in CDl8 mAb/SOD, CDl8 mAb and SOD groups(p < 0.01). MPO activity was significantly decreased in CDl8 mAb group as compared with SOD group. (p < 0.01). 3. MDA content was significantly decreased in CDl8 mAb/SOD, CDl8 mAb and SOD groups (p < 0.01), but the difference between CDl8 mAb and SOD groups was not significant. From those above results, we get to the conclusion that blocking neutrophil adherence and/or aggregation with monoclonal antibodies to CDl8 as compared with radical scavenger significantly ameliorates reperfusion injury. It is suggested that combination of modalities with antiadhesion therapy and radical scavenger may have a synergistic effect of improving flap survival and may be the optimal prevention of ischemiareperfusion injury.

Prevention of reperfusion injury with CD18 monoclonal antibody and superoxide dismutase

Prolonged ischemia results in cellular necrosis and only prompt restoration of blood flow will prevent this type of injury. However, reperfusion itself can cause significant injury of previously ischemic tissue, i.e. "reperfusion injury'. This is an issue of concern in many areas of reconstructive surgery including free tissue transfer and replantation. Many factors have been implicated in the cause of reperfusion injury. Oxygen free radicals have enjoyed increasing popularity recently, but leukocytes had been thought to have a role only in the healing process that follows ischemic injury. Current studies in myocardium, liver and intestine have shown a dramatic increase in tissue leukocytes after ischemia-reperfusion and evidence implicating leukocytes in pathogenesis of ischemia-reperfusion injury has come from studies demonstrating significant injury reduction by depletion of circulating neutrophils. Therefore, increased neutrophil adhesiveness is a critical early step in the sequence of events leading to neutrophil-mediated injury. The purpose of this study is to evaluate the effect of CDl8 monoclonal antibody(CDl8 mAb), blocking antibody of neutrophil adherence, and superoxide dismutase (SOD), free radical scavenger, on reperfusion injury in rat epigastric island skin flap. The epigastric pedicle was occluded for six hours with ambient temperature at 22+/-1degrees C. The epigastric nerve was carefully dissected out and left intact to minimize autocannibalization. The flaps were sutured back down to their beds over interposed silicone sheets to prevent plasmatic imbibition. Fifteen minutes before reperfusion, the flaps were perfused with saline, CDl8 mAb(1 mg/kg), SOD(20,000 unit/kg) or CDl8 mAh/SOD(1 mg/kg + 20,000unit/kg). Percentage of flap survival was assessed by computerized planimetry on the seventh day. Tissue biopsies for myeloperoxidase(MPO) and malonyldialdehyde (MDA) were obtained at 24 hours after reperfusion. The results were as follows. 1. Percentage of flap survival was significantly increased in CDl8 mAb/SOD, CDl8 mAb and SOD groups in order, compared to the control(P < 0.05). Percentage of flap survival was significantly increased in CDl8 mAb group as compared with SOD group(p < 0.05). Percentage of flap survival significantly increased in CDl8 mAb/SOD group as compared with CDl8 mAb and SOD groups(p < 0.05) 2. MPO activity was significantly decreased in CDl8 mAb/SOD, CDl8 mAb and SOD groups(p < 0.01). MPO activity was significantly decreased in CDl8 mAb group as compared with SOD group. (p < 0.01). 3. MDA content was significantly decreased in CDl8 mAb/SOD, CDl8 mAb and SOD groups (p < 0.01), but the difference between CDl8 mAb and SOD groups was not significant. From those above results, we get to the conclusion that blocking neutrophil adherence and/or aggregation with monoclonal antibodies to CDl8 as compared with radical scavenger significantly ameliorates reperfusion injury. It is suggested that combination of modalities with antiadhesion therapy and radical scavenger may have a synergistic effect of improving flap survival and may be the optimal prevention of ischemiareperfusion injury.

Plasmatic imbibition and revascularization in venousisland flap

Several mechanisms about venous flap were proposed. Among them, plasmatic imbibition and early revascularization are supposed to be the most important factors for the survival of venous flap. Many reports about the role of plasmatic imbibition have used silastic sheet or other foreign material to block the plasmatic imbibition so that foreign body reaction might affect the survival of the flap. No experiment has been reported to examine the revascularization directly. We blocked the plasmatic imbibition by marginal resection around the venous island flap and delayed venous island flap and placing it onto the bare cartilage to exclude the effect of foreign body. We also examined the revasularization of the delay and non-delay venous island flap directly using microfil cast. As a result blocking of the plasmatic imbibition markedly decrease the survival of the flap but the survival of delay flap is about five times that of non delay flap. Revascularization was minimal at 1 week postoperative day. It is inferred that plasmatic imbibition is more important than revascularization.

Plasmatic imbibition and revascularization in venousisland flap

Several mechanisms about venous flap were proposed. Among them, plasmatic imbibition and early revascularization are supposed to be the most important factors for the survival of venous flap. Many reports about the role of plasmatic imbibition have used silastic sheet or other foreign material to block the plasmatic imbibition so that foreign body reaction might affect the survival of the flap. No experiment has been reported to examine the revascularization directly. We blocked the plasmatic imbibition by marginal resection around the venous island flap and delayed venous island flap and placing it onto the bare cartilage to exclude the effect of foreign body. We also examined the revasularization of the delay and non-delay venous island flap directly using microfil cast. As a result blocking of the plasmatic imbibition markedly decrease the survival of the flap but the survival of delay flap is about five times that of non delay flap. Revascularization was minimal at 1 week postoperative day. It is inferred that plasmatic imbibition is more important than revascularization.