Capsule induction technique in a rat model for bladder wall replacement: an overview

The search for a reliable technique for functional genitourinary tissue replacement remains a challenging task. The most recent advances in cell biology and tissue engineering have utilized various avascular and acellular collagen scaffolds with or without seeded cells. These techniques, however, are frequently complicated by tissue necrosis, contracture and resorption due to limited vascularization. We employed a new three-stage, evolving animal model with stage I optimizing the culture delivery vehicle, stage II employing a seeded vascularized capsule flap, and stage III adding a contractile matrix in the form of pedicled gracilis muscle prelaminated with autologous, in vitro-expanded urothelial cells to reconstruct an entire supratrigonal bladder-wall defect in rats.Specimens stained with hematoxylin and eosin (H&E), alpha(1)-actin staining, and a specific immunohistochemical staining (AE(1)&AE(3)-anticytoceratin monoclonal antibody stain) showed a continuous, multilayered, functioning urothelial lining along the transposed prelaminated gracilis flap in the animals of the final-stage experiment. Successful urinary reconstruction requires a contractile neoreservoir resistant to resorption over time and a stable, protective urothelial lining. We demonstrated that a gracilis muscle flap can be seeded with autologous cultured urothelial cells suspended in fibrin glue. This prelaminated flap can be safely transposed onto its pedicle and become successfully integrated into the remaining bladder wall, demonstrating urothelial lining and the potential to contract. Further studies in larger animals with urodynamic assessment is warranted to determine if this type of bladder-wall replacement technique is suitable for urinary reconstruction in humans.

Safe treatment of trigger finger with longitudinal and transverse landmarks: an anatomic study of the border fingers for percutaneous release

Transverse landmarks have recently been determined to predict the proximal and distal edges of the A1 pulley for trigger finger release. Percutaneous A1 pulley release has been discouraged for the border digits because of the risk of injury to the neurovascular structures of the index and small fingers. The purpose of the study was to identify longitudinal surface landmarks to prevent injury to the neurovascular bundles during percutaneous A1 pulley release of the ulnar and radial border digits. Longitudinal surface landmarks were identified and marked on 29 cadaver hands. Proximal and distal landmarks for the longitudinal vector through which the A1 pulley of the small finger was released include the midline of the proximal digital crease and the scaphoid tubercle. Proximal and distal landmarks for the longitudinal line through which the index finger A1 pulley was released include the midline of proximal digital crease and radial edge of the pisiform. Longitudinal incisions were performed between these landmarks, straight through the skin and deep enough to score the A1 pulley. The distance of the medial edge of the neurovascular structures from the longitudinal incision in the A1 pulley was measured for each small finger and index finger. Using these longitudinal landmarks for the index and small fingers, none of the neurovascular structures was injured while performing these longitudinal incisions through the skin, scoring the A1 pulley. In fact, the average distance for the neurovascular structures from the longitudinal vector of the small finger was 5.4 +/- 1.4 mm radially and 6.7 +/- 1.9 mm ulnarly. The average distance for the neurovascular structures from the longitudinal line of the index finger was 8.5 +/- 1.8 mm radially and 6.2 +/- 1.7 mm ulnarly. Based on the findings of this anatomical study, these longitudinal landmarks can be used to avoid injury to neurovascular structures in the management of trigger finger involving the border digits with steroid-injection, open, or percutaneous A1 pulley release.

Facial fracture approaches with landmark ratios to predict the location of the infraorbital and supraorbital nerves: an anatomic study

In exposing facial fractures for reduction and fixation with coronal, subciliary, subtarsal, and upper buccal sulcus approaches, the supraorbital and infraorbital nerves are susceptible to injury. The location of the supraorbital and infraorbital nerves can be predicted by palpating for the supraorbital notch. Significant edema as seen with facial fractures can make these prominent bony landmarks difficult to palpate, however. The purpose of this study was to determine a method to predict the location of the supraorbital and infraorbital nerves in the face of frontal and periorbital edema when the supraorbital and infraorbital nerves are not palpable. The supraorbital and infraorbital nerves were identified in 14 cadaver heads. The orbital width from the medial to lateral canthus was measured. The distance of the vertical vector of the supraorbital and infraorbital nerves from the medial canthus was measured along this horizontal vector of the orbit. The distance of the infraorbital nerve from the infraorbital rim was measured. The orbital width measured 42.2 +/- 1.6 mm from the medial to lateral canthus. The vertical vector of the supraorbital nerve measured 15.9 +/- 1.1 mm from the medial canthus along the horizontal vector of the orbit. The vertical vector of the infraorbital verve measured 16.8 +/- 1.4 mm from the medial canthus along the horizontal vector of the orbit. The infraorbital nerve measured 9.8 +/- 1.0 mm inferior to the infraorbital rim. The medial one third of the orbit measured 14.1 mm. Therefore, the supraorbital and infraorbital nerves are located approximately along the medial third of the orbit, with the upper bound of 95% confidence at 3.1 mm. The location of the supraorbital and infraorbital nerves can be predicted by the previous landmark ratio to within 3 mm.

Surface landmarks to locate the thenar branch of the median nerve: an anatomical study

The thenar branch of the median nerve can be injured during carpal tunnel release. The purpose of this study was to identify surface landmarks to consistently predict the location of the thenar branch of the median nerve. Surface landmarks were marked and incised in 28 cadaveric hands. The incisions were made along the longitudinal line of the third web space and the horizontal cardinal line from the hamate hook to the ulnar border of the thumb. The origin of the thenar branch was determined in relation to these longitudinal and horizontal vectors. The origin of the thenar nerve branch was consistently observed in the radial proximal quadrant formed by the aforementioned longitudinal and horizontal vectors. The thenar branch origin was observed to be an average of 8.6 +/- 1.9 mm radial to the longitudinal axis along the third web space. The origin of the thenar branch was observed to be an average of 6.3 +/- 2.0 mm proximal to the horizontal axis between the hamate hook and the ulnar border of the thumb. The thenar branch was observed precisely at the intersection of the longitudinal vector from the second web space to the scaphoid tubercle and the horizontal vector from the hamate hook to the radial edge of the proximal metacarpophalangeal crease in all 28 cadaveric hands. On the basis of these 28 cadaveric dissections, the location of the thenar branch of the median nerve can be predicted by the intersection of the longitudinal vector from the second web space to the scaphoid tubercle and the horizontal vector from the hamate hook to the radial aspect of the metacarpophalangeal crease.

The safe face lift with bony anatomic landmarks to elevate the SMAS

The risk for facial nerve injury has been reported to be increased with the inclusion of superficial musculoaponeurotic system (SMAS) elevation as compared with a skin-only face lift. The facial nerve courses through the parotid gland. The SMAS is elevated superficial to the parotid gland. However, in elevating the SMAS anterior to the parotid gland, the facial nerve is at risk of injury where its branches emerge from the anterior edge of the parotid gland. The purpose of this study was to identify bony anatomic landmarks to predict the location of the anterior edge of the parotid gland to avoid injury to the facial nerve branches as they exit the parotid gland. The authors dissected 20 cadaver face halves to determine bony landmarks-the masseteric tuberosity and the inferior lateral orbital rim-to predict the location of the anterior parotid edge. Then they measured the anterior edge of the parotid gland in relation to the vector formed between these two bony landmarks. They identified and measured the most anterior portion of the parotid gland in relation to this vector. Then the most posterior aspect of the parotid gland in relation to this vector was measured. In the 20 dissections, the authors found the most anterior portion of the parotid gland to be 2.7 +/- 1.0 mm anterior to the vector from the inferior lateral orbital rim to the masseteric tuberosity. The most posterior part of the anterior edge of the parotid gland in relation to this vector was found to be 1.0 +/- 1.5 mm posterior to this vector. The parotid gland measured an average of 38.8 +/- 3.5 mm in width from the tragus to the anterior parotid edge. In elevating the SMAS with a face lift, the facial nerve branches can be predicted to exit the anterior edge of the parotid gland, which can be located 38.8 mm anterior to the tragus and near the vector from the inferior lateral orbital wall to the masseteric tuberosity.

Age-related differences of neutrophil activation in a skeletal muscle ischemia-reperfusion model

Free tissue transfers and replantation of amputated limbs are better tolerated by young adolescents than mature adults. The authors hypothesized that this observation may be, in part, because of an attenuated ischemia-reperfusion (IR) injury in younger patients. Because neutrophils have been identified as a critical cell line responsible for IR injury, the authors investigated the effects of animal age on the degree of neutrophil activation in a rat model. Activation was evaluated by monitoring expression of integrin surface markers (mean fluorescence intensity [MFI] of CD11b) and oxidative burst potential (MFI of dihydrorhodamine [DHR] oxidation) by flow cytometry in neutrophils analyzed after 4 hours of ischemia and 1, 4, and 16 hours of reperfusion in a gracilis muscle flap model in mature adult and young adolescent rats. Neutrophil activation was also evaluated in control sham-operated animals, which underwent elevation of gracilis muscle flaps without exposure to an ischemic insult. Muscle edema, determined by wet-to-dry muscle weight ratio, and muscle viability, determined by nitro blue tetrazolium (NBT) staining, were completed for gracilis muscles exposed to ischemia after 24 hours of reperfusion for each of the groups. Integrin expression, assessed by MFI of CD11b, was increased significantly in ischemic muscles of mature adult rats at 4 hours of reperfusion (71.10+/-3.53 MFI vs. 54.88+/-12.73 MFI, p=0.025). Neutrophil oxidative potential, assessed by MFI of DHR oxidation, was increased significantly in ischemic muscles of mature adult rats compared with young adolescent rats at 1 hour of reperfusion (78.10+/-9.53 MFI vs. 51.78+/-16.91 MFI, p=0.035) and 4 hours of reperfusion (83.69+/-15.29 MFI vs. 46.55+/-8.09 MFI, p=0.005). Increased edema formation was observed in the ischemic muscles of mature adult rats when compared with young adolescent rats (1.25+/-0.04 vs. 1.12+/-0.05, p=0.031) after 24 hours of reperfusion. A trend toward decreased muscle viability was observed in the mature adult rats when compared with young adolescent rats (23.7+/-3.1% NBT staining vs. 32.3+/-13.7% NBT staining, p=0.189) after 24 hours of reperfusion. The authors present evidence of an attenuated IR injury in young adolescent animals when compared with mature adult rats. These findings emphasize the importance that studies involving IR injury should be performed with consideration of animal age.

Treatment of infected wounds with the antimicrobial peptide D2A21

BACKGROUND

Infected wounds impose a significantly negative effect on patient care and recovery, as infection hinders normal wound healing, resulting in increased patient morbidity and mortality. More attention is being focused on addressing the problem of multidrug-resistant bacteria and the staggering costs and consequences resulting from this. Recently, newly evaluated antimicrobial peptides have been shown to be active against a wide variety of bacteria in in vitro studies. This study evaluates the use of a particular antimicrobial peptide, D2A21 (Pittsburgh, PA), to combat infection in an acutely infected wound model.

METHODS

Forty-eight Wistar rats were used to compare the effects of D2A21 to control vehicle, silver sulfadiazine (SSD), and Sulfamylon in this model. Two 1.5 x 1.5-cm full-thickness defects were created on the rat dorsum and were subsequently inoculated with 108 Pseudomonas aeruginosa. Animals underwent daily treatment with either D2A21 gel, control vehicle, SSD, or Sulfamylon. Animals were evaluated for survival differences.

RESULTS

Survival analysis at 21 days for the different treatment groups were as follows: 100% for the D2A21-treated animals, 50% for control-treated animals, 83% for Sulfamylon-treated animals, and 33% for SSD-treated animals.

CONCLUSION

D2A21 antimicrobial peptide demonstrates significant activity compared with controls and standards of therapy. The promising effect of this topical peptide is clearly evident as shown by this study, and its further investigation as a potential agent in the fight against infected or chronic wounds is warranted.

Outcomes after mutilating hand injuries: review of the literature and recommendations for assessment

The functional outcome of a mutilating hand injury cannot be fully assessed at the time of injury alone. The measure of functional outcome must incorporate the evaluation and severity of the initial injury and the subsequent reconstructive surgeries. The complexity of the hand deserves no less. Restoration of prehensile function is the top priority in reconstruction following mutilating hand injuries, and assessment of outcome should address this goal. Flaps and specialized tissue grafts can restore architecture and balance in the hand. One can reconstruct a thumb and fingers with the big toe and smaller toes to give a functional sensate grip. The assessment of functional outcome should include not only objective measures but also subjective questionnaires that focus on issues most relevant to the patient. The use of questionnaires that have been shown to be valid, reliable, consistent, responsive, and sensitive allows the most meaningful conclusions about and comparisons between treatments. Perhaps because of the unique challenges presented by mutilating hand injuries, a new instrument, specific to mutilating hand injury, may provide the most beneficial information to guide treatment and assess outcome.

Mutilating hand injuries: principles and management

The objectives of the treatment of mutilating hand injuries are to insure patient's survival, limb survival and ultimately limb function. Initially, patients are stabilized and cleared of other potentially life threatening trauma. The cornerstone to the early intra-operative management of the mangled hand includes irrigation and debribement. Skeletal stabilization, revascularization, replantation or the use of spare parts to restore functions are addressed at the initial surgery. Subsequent second or third look surgeries may be required to procure a clean wound bed. Regional flaps and free tissue transfer provides definitive coverage than soft tissue is required. Secondary procedures such as tenolysis, joint mobilization or toe transfers may be needed to restore dexterity to the healed yet dysfunctional hand. Adherence to sound safe principles help prevent further mobidity while fostering the restoration of hand function to return the patient to gainful activities.

Local hypothermia during early reperfusion protects skeletal muscle from ischemia-reperfusion injury

Amputated tissue maintained in a hypothermic environment can endure prolonged ischemia and improve replantation success. The authors hypothesized that local tissue hypothermia during the early reperfusion period may provide a protective effect against ischemia-reperfusion injury similar to that seen when hypothermia is provided during the ischemic period. A rat gracilis muscle flap model was used to assess the protective effects of exposing skeletal muscle to local hypothermia during ischemia only (p = 18), reperfusion only (p = 18), and both ischemia and reperfusion (p = 18). Gracilis muscles were isolated and exposed to hypothermia of 10 degrees C during 4 hours of ischemia, the initial 3 hours of reperfusion, or both periods. Ischemia-reperfusion outcome measures used to evaluate muscle flap injury included muscle viability (percent nitroblue tetrazolium staining), local edema (wet-to-dry weight ratio), neutrophil infiltration (intramuscular neutrophil density per high-power field), neutrophil integrin expression (CD11b mean fluorescence intensity), and neutrophil oxidative potential (dihydro-rhodamine oxidation mean fluorescence intensity) after 24 hours of reperfusion. Nitroblue tetrazolium staining demonstrated improved muscle viability in the experimental groups (ischemia-only: 78.8 +/- 3.5 percent, p < 0.001; reperfusion-only: 80.2 +/- 5.2 percent, p < 0.001; and ischemia-reperfusion: 79.6 +/- 7.6 percent, p < 0.001) when compared with the nonhypothermic control group (50.7 +/- 9.3 percent). The experimental groups demonstrated decreased local muscle edema (4.09 +/- 0.30, 4.10 +/- 0.19, and 4.04 +/- 0.31 wet-to-dry weight ratios, respectively) when compared with the nonhypothermic control group (5.24 +/- 0.31 wet-to-dry weight ratio; p < 0.001, p < 0.001, and p < 0.001, respectively). CD11b expression was significantly decreased in the reperfusion-only (32.65 +/- 8.75 mean fluorescence intensity, p < 0.001) and ischemia-reperfusion groups (25.26 +/- 5.32, p < 0.001) compared with the nonhypothermic control group (62.69 +/- 16.93). There was not a significant decrease in neutrophil CD11b expression in the ischemia-only group (50.72 +/- 11.7 mean fluorescence intensity, p = 0.281). Neutrophil infiltration was significantly decreased in the reperfusion-only (20 +/- 11 counts per high-power field, p = 0.025) and ischemia-reperfusion groups (23 +/- 3 counts, p = 0.041) compared with the nonhypothermic control group (51 +/- 28 counts). No decrease in neutrophil density was observed in the ischemia-only group (40 +/- 15 counts per high-power field, p = 0.672) when compared with the nonhypothermic control group (51 +/- 28 counts). Finally, dihydrorhodamine oxidation was significantly decreased in the reperfusion-only group (45.83 +/- 11.89 mean fluorescence intensity, p = 0.021) and ischemia-reperfusion group (44.30 +/- 11.80, p = 0.018) when compared with the nonhypothermic control group (71.74 +/- 20.83), whereas no decrease in dihydrorhodamine oxidation was observed in the ischemia-only group (65.93 +/- 10.3, p = 0.982). The findings suggest a protective effect of local hypothermia during early reperfusion to skeletal muscle after an ischemic insult. Inhibition of CD11b expression and subsequent neutrophil infiltration and depression of neutrophil oxidative potential may represent independent protective mechanisms isolated to local tissue hypothermia during the early reperfusion period (reperfusion-only and ischemia-reperfusion groups). This study provides evidence for the potential clinical utility of administering local hypothermia to ischemic muscle tissue during the early reperfusion period.

Dorsalis pedis arterial pulse: palpation using a bony landmark

INTRODUCTION

The unreliability of the pulse examination of the foot has primarily been due to variability of technique between examiners. Whereas the groove between the medial malleolus and the Achilles tendon more readily defines the location of the posterior tibial pulse, the location of the dorsalis pedis pulse remains vague. In this paper a novel method of locating the dorsalis pedis pulse by physical examination is described.

METHODS

Forty one consecutive patients admitted to a general surgery service of a tertiary medical centre within a two month period were examined. Using the dorsal most prominence of the navicular bone as a landmark, the distance to the dorsalis pedis pulse in bilateral lower extremities was measured by palpation and compared to Doppler ultrasound. Measurements were confirmed by two separate examiners blinded to each others' results.

RESULTS

The dorsalis pedis artery was palpable in 78% of extremities and present by Doppler ultrasound in 95%. The location of the left dorsalis pedis artery was a mean (SD) 9.8 (1.4) mm by palpation and 11.1 (2.1) mm by Doppler ultrasound from the dorsal most prominence of the navicular bone. The right dorsalis pedis artery was 10.4 (3.4) mm by palpation and 11.5 (0.7) mm from the dorsal most prominence of the navicular bone. No significant differences in location of the dorsalis pedis artery were observed bilaterally between Doppler ultrasound and palpation; No significant differences were observed comparing contralateral dorsalis pedis arteries nor any differences between the examiners' results.

CONCLUSION

The dorsal most prominence of the navicular bone provides a bony landmark to readily locate the dorsalis pedis artery. Reliability of the examination may be increased as to the patency of the dorsalis pedis artery by using this dependable anatomic landmark.

Tumors of the perionychium

Tumors of the perionychium are often subtle and difficult to diagnose. Because they are somewhat uncommon, the early symptoms of these tumors, which may include vague pain, local swelling, nail discoloration, nail deformity, or drainage, may be mistaken for signs of infection and/or trauma and therefore treated with topical or oral antibiotics for some time. Functionally important in enhancing fingertip sensation, protection, and manipulating fine objects, the perionychium is continuously subject to day-to-day trauma and injury that can alter the natural contours and growth patterns of the nail plate. Bacterial, viral, or fungal infections can incite swelling, pain, and distortion of the perionychium as well. Both infection and trauma, then, can mask underlying tumors or growths that would delay their diagnosis. A delay in treatment can be devastating if the growth of the perionychium happens to be malignant. Therefore, a general understanding of the signs and symptoms of the perionychium tumors is needed by all physicians and surgeons treating nail problems.

Lower blepharoplasty using bony anatomical landmarks to identify and avoid injury to the inferior oblique muscle

In the resection of redundant orbital fat during lower blepharoplasty, selective excision is performed from the medial, central, and lateral compartments. During transcutaneous blepharoplasty, the inferior oblique muscle is susceptible to injury because of its intimate association between the medial and central compartments. When performing a transconjunctival approach, the inferior oblique muscle is even more susceptible to injury because it lies in the direct path of dissection for fat pad exposure. Injury to the inferior oblique muscle can result in symptoms ranging from transient diplopia to a more debilitating permanent strabismus. Fresh cadaver heads were used to identify bony anatomical landmarks that would help to more accurately define the origin and body of the inferior oblique muscle. The orbital rim, infraorbital foramen, and supraorbital notch were chosen as guideline landmarks. The origin of the inferior oblique muscle was designated with respect to the above structures, and the muscle course was delineated. The inferior oblique muscle originates on the orbital floor, 5.14 +/- 1.21 mm posterior to the inferior orbital rim, on a line extending from the infraorbital foramen to 10 +/- 0.9 mm inferior to the supraorbital notch along the supramedial orbital rim. The muscle belly extends from this origin to its insertion into the posterolateral globe in an oblique direction toward the lateral canthal area. Identification of the orbital rim, infraorbital foramen, and supraorbital notch more accurately localizes the origin and course of the inferior oblique muscle, which may facilitate fat resection during lower blepharoplasty by preventing morbidity associated with inferior oblique muscle injury.

Aggressive digital papillary adenocarcinoma presenting as finger infection

Aggressive digital papillary adenocarcinoma (ADPA) is a rare tumor of sweat gland origin that may present in a nonspecific manner on the finger. The authors report a case of ADPA that was treated initially as a chronic infection of the finger, leading to a delay in diagnosis and definitive treatment. Failure of the wound to heal led to a biopsy of the lesion, which revealed ADPA. Because of the potential for aggressive local growth and distant metastases, amputation was indicated. This case demonstrates the importance of considering ADPA in the differential diagnosis of nonhealing wounds of the finger that have not responded to other forms of treatment. Wide local excision with clear margins and close surveillance for signs of recurrence or metastasis are indicated for this rare sweat gland neoplasm.

Successful transplantation of three tissue-engineered cell types using capsule induction technique and fibrin glue as a delivery vehicle

Recent advances in cell biology and tissue engineering have used various delivery vehicles for transplanting varying cell cultures with limited success. These techniques are frequently complicated by tissue necrosis, infection, and resorption. The purpose of this study was to investigate whether urothelium cells, tracheal epithelial cells, and preadipocytes cultured in vitro could be successfully transplanted onto a prefabricated capsule surface by using fibrin glue as a delivery vehicle, with the ultimate goal for use in reconstruction. In the first step of the animal study, tissue specimens (bladder urothelium, tracheal epithelial cells, epididymal fat pad) were harvested for in vitro cell culturing, and a silicone block was implanted subcutaneously or within the anterior rectus sheath to induce capsule formation. After 6 to 10 days, when primary cultures were confluent, the animals were re-anesthetized, the newly formed capsule pouches were incised, and the suspensions of cultured urothelia cells (n = 40), tracheal epithelial cells (n = 32), and preadipocytes (n = 40) were implanted onto the capsule surface in two groups, one using standard culture medium as a delivery vehicle and the second using fibrin glue. Histologic sections were taken, and different histomorphologic studies were performed according to tissue type. Consistently in all animals, a highly vascularized capsule was induced by the silicon material. In all animals in which the authors used fibrin glue as a delivery vehicle, they could demonstrate a successful reimplantation of cultured urothelium cells, tracheal epithelial cells, or preadipocytes. Their animal studies showed that capsule induction in combination with fibrin glue as a delivery vehicle is a successful model for transplantation of different in vivo cultured tissue types.

Outcome analysis of reduction mammaplasty using the modified Robertson technique

The benefits of reduction mammaplasty have been well documented in previous literature. Anticipating and correcting for pseudoptosis (bottoming-out), however, can impair the cosmetic outcome as the inferior skin envelope stretches and lengthens over time. We present long-term results on patients using the modified Robertson technique for reduction mammaplasty, which appears to have significant benefit in helping to prevent bottoming-out. Surveys were sent to patients undergoing reduction mammaplasty surgery with this technique from 1987 to 1997. Patients were queried regarding preoperative and postoperative symptoms, satisfaction, and outcome related to their surgery and were also offered free follow-up examinations. The patients who returned for follow-up were then evaluated by the attending surgeons for evaluation of scarring, nipple position, ptosis, pseudoptosis, shape, and overall appearance. Reduced breasts were also compared with cosmetically optimal breasts to compare for measured levels of pseudoptosis using our defined visual inferior pole ratio measurements. Average reduction size was 910 g and follow-up was 4.7 years from the time of surgery. There was significant improvement demonstrated in all areas questioned, with the greatest relief shown in back and shoulder pain, shoulder grooving, and difficulty fitting clothing. There was also demonstrated to be significantly less use of medical modalities postoperatively and significant increases in activity levels. Satisfaction for size, shape, symmetry, and overall results was 85, 94, 98, and 94 percent, respectively. Evaluations for pseudoptosis by the attending surgeons were rated good or excellent in 95 percent of patients. Measurements of the visual inferior pole ratio for pseudoptosis also demonstrated no significant differences when compared with aesthetically optimal breasts. The modified Robertson reduction mammaplasty is a reliable technique that can be used for both small and large reductions, giving both reliable and consistent results. This technique significantly improves symptoms, as do other reduction techniques, but has the added advantage of helping to avoid pseudoptosis postoperatively.

Improvement in burn wound infection and survival with antimicrobial peptide D2A21 (Demegel)

Naturally occurring antimicrobial peptides have been discovered in both plants and animals. Many of these peptides demonstrate impaired activity or cytotoxicity when applied exogenously. Synthetically engineered antimicrobial peptides have been designed to increase potency and activity against bacteria and fungus yet remain noncytotoxic. The antimicrobial peptide D2A21 (Demegel) has already demonstrated significant activity in vitro against many common hospital pathogens. The purpose of this study was to evaluate the effects of D2A21 in an in vivo infected burn-wound model, examining both quantitative cultures of the wound and survival of the animal. Forty-four Wistar rats were subjected to a 23 percent total body surface area scald burn. Pseudomonas aeruginosa was administered topically with 108 organisms and wounds were then evaluated at day 1, 2, or 3 for eschar and subeschar muscle quantitative culture. The experimental group was treated daily with 1.5% topical D2A21. The control group was treated with control gel. A second group of Wistar rats (n = 14) were burned and given a 107 inoculum of the same Pseudomonas and evaluated to 14 days for survival and weight changes. This group was subdivided into rats receiving either topical D2A21 or control base daily. The quantitative biopsy results demonstrated that D2A21-treated wounds had no bacterial growth in burn eschar at day 2 or 3, whereas control animals demonstrated growth at greater than 105 organisms by day 2. Subeschar muscle cultures also demonstrated significantly less bacterial invasion compared with controls on each day tested. D2A21-treated animals had an 85.7 percent survival compared with 0 percent survival in controls. Furthermore, the D2A21-treated groups demonstrated maintenance of body weights, whereas controls had significant weight loss with time. In conclusion, D2A21 demonstrates significant antibacterial activity against Pseudomonas, sterilizing burn eschar and decreasing subeschar bacterial load, allowing for a markedly significant improvement in survival in this infected burn-wound model.

Operative repair of a chronic, ulnar proximal interphalangeal dislocation of the little finger with an excellent functional result

Chronic dislocations of the proximal interphalangeal joint are not common. The instability and physical impairment, however, can render the digit or hand quite dysfunctional. A case report of the reconstruction of a nine-year chronic proximal interphalangeal joint dislocation of the left little finger is presented. The functional recovery is described. A literature review of the treatment of chronic dislocations of the proximal interphalangeal joint is also discussed.

Upper blepharoplasty with bony anatomical landmarks to avoid injury to trochlea and superior oblique muscle tendon with fat resection

The trochlea and superior oblique muscle tendon separate the medial and central fat compartments in the upper lid. The purpose of this study was to determine anatomical landmarks to predict the location of and avoid injuring the trochlea and superior oblique muscle tendon with orbital fat resection during upper blepharoplasty. The trochlea and superior oblique muscle tendon were identified in 14 cadaver heads. Bony anatomical landmarks were identified to predict the oblique vector along which the trochlea and superior oblique tendon lie. The trochlea was measured in millimeters from the palpable superior orbital foramen. The oblique course of the superior oblique muscle tendon was measured from its medial location in the lateral direction in millimeters from the frontozygomatic suture. These measurements were obtained with 4.0-power loupe magnification. The trochlea was identified 10.0 +/- 0.9 mm inferior to the palpable superior orbital foramen. The superior oblique muscle tendon coursed laterally along an oblique vector to within 1 mm of the frontozygomatic suture for all 14 dissections. The vertical vector of the superior orbital foramen was measured 15.9 +/- 1.1 mm lateral to the medial canthus. The width of the bony orbit measured 42.2 +/- 1.6 mm. In two dissections, the superior orbital foramen could not be palpated, and the latter measurements were used to predict the superior orbital foramen. This anatomical study showed that when performing orbital fat resection with upper blepharoplasty, the trochlea and superior oblique muscle tendon can be identified and avoided with the above-described bony landmarks.

Effects of liposome-mediated gene transfer of VEGF in ischemic rat gracilis muscle

The purpose of the current study was to determine the effects of vascular endothelial growth factor (VEGF) on muscle flap survival and vascularity in a rat gracilis ischemia-reperfusion model. A total of 12 adult male Wistar rats were divided into two groups (n = 6). The experimental group received the plasmid encoding VEGF(165) cDNA plus lipofectamine (cationic liposome) injected directly to the gracilis muscle following 4 h of ischemia. The control group received lipofectamine only. The viability and vascularity of the flaps were evaluated after 7 days of reperfusion. The data demonstrated that the VEGF plasmid- and lipofectamine-treated muscle flaps had significantly greater total survival and capillary count 7 days after reperfusion compared with the flaps treated only with lipofectamine. These results indicate that VEGF exerts a protective effect on ischemic skeletal muscle flaps.

Transplantation of tracheal epithelial cells onto a prefabricated capsule pouch with fibrin glue as a delivery vehicle

OBJECTIVE

The purpose of this study was to investigate whether in vitro cultured tracheal epithelial cells can be transplanted onto a prefabricated capsule surface in vivo for possible use in tracheal reconstruction.

METHODS

Tracheal epithelial cells from 12 donor inbred rats were harvested for culture and expansion. In 16 recipient inbred rats, 2 sterile cylinders made of silicone rubber were implanted in each rat bilaterally in the folds of both the left and right anterior rectus sheath by wrapping the sheaths around the cylinders to induce a capsule formation. Ten days later, the cell cultures were divided and suspended in 1 of 2 delivery vehicles (standard culture medium or fibrin glue) and implanted onto the capsule surface. To compare the 2 delivery vehicles, we used fibrin glue on one side and the standard culture medium on the other.

RESULTS

After 2 (group 1, n = 8) and 4 (group 2, n = 8) weeks, histologic findings, immunohistochemical staining, and electron microscopy demonstrated the capsule to be covered with a tracheal neoepithelium in group 1 and additional ciliated cells and secretory cells in a confluent layer in group 2 but only on the side with fibrin glue as the delivery vehicle. No viable epithelial cells were identified on the side with the standard culture medium in either group.

CONCLUSION

We conclude that cultured epithelial cells can be successfully transplanted onto a prefabricated capsule surface with fibrin glue, which will differentiate into morphologic, nearly normal epithelium, showing potential for tracheal reconstruction.