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DNA microarray gene expression analysis was conducted in human umbilical vein endothelial cells (HUVECs) and coronary artery endothelial cells (HCAECs) exposed to laminar or turbulent shear stress. Approximately 3% of the total 5600 gene in HUVECs and HCAECs increased their expression more than two-fold or decreased it to less than half the static control in response to an arterial level of laminar shear stress (15 dynes/cm(2) for 24 hours). The proportions of shear-stress-responsive genes decreased to around 2% under the venous level of laminar shear stress (1.5 dynes/cm(2)) in both cell lines. Turbulent shear stress of 1.5 dynes/cm(2) altered the expression of 1.1% of all genes in the HCAECs. Laminar shear stress, but not turbulent shear stress, decreased the expression of a number of genes involved in DNA synthesis and the cell cycle in both HUVECs and HCAECs. Clustering analysis showed a variety of temporal profiles of gene expression in HUVECs exposed to laminar shear stress of 15 dynes/cm(2) for 3, 6, 12, 24, and 48 hours. Turbulent shear stress affected expression of many genes that play a role in vascular remodeling, including genes encoding plasminogen activators and their inhibitor, endothelin-1, transforming growth factor-beta, collagen type IV, and ephrin A1.

CATCH 22 syndrome is characterized by cardiac defects, abnormal facial features, thymic hypoplasia, cleft palate, and hypocalcemia. It results from a deletion within chromosome 22q11. This syndrome is not a simple disease. It includes DiGeorge syndrome, conotruncal anomaly face syndrome, and velocardiofacial syndrome. The authors report two cases of CATCH 22 syndrome.

To investigate whether hyperthermic preconditioning can actually protect skin flaps against ischemia/reperfusion injury, the authors first developed a new skin-flap model in 15 mice, a dorsal bipedicle island skin-flap model. Then, another 75 mice were separated into five groups. Mice in Groups 1 to 4 received the same hyperthermic preconditioning, but had different recovery times of 6 hr, 24 hr, 48 hr, and 72 hr, respectively. Mice in Group 5 served as control. Island skin flaps were elevated in all groups, and then were subjected to 8 hr of ischemia and subsequent reperfusion. Flap survival was statistically significantly higher than in controls in animals in Groups 1 and 3, with recovery times of 6 hr and 48 hr, respectively. Mice in Groups 2 and 4 had recovery times of 24 hr and 72 hr, respectively. Hyperthermic preconditioning could thus protect skin flaps against ischemia/reperfusion injury, and there were two optimal periods for such a protective effect.

Since ischemia-reperfusion injury continues to be a major problem in reconstructive microsurgery, improvement of experimental models is still desirable. We developed a model that allows direct visualization of flap microcirculation in mice by intravital microscopic techniques. A newly designed skinfold chamber was installed on the dorsum of mice, and microcirculation was inspected with an intravital microscope. An island flap, nourished by the deep circumflex iliac arteries, was elevated after implantation of the chamber, allowing visualization of the microcirculation in the island flap. The island flap was exposed to global ischemia by clamping the pedicles, and the clamps were then released to allow reperfusion. Various microcirculatory responses induced by ischemia-reperfusion were visualized. This model accurately simulated the clinical situation in reconstructive surgery and successfully realized chronic visualization of the flap microcirculation in vivo., (Copyright 2002 Wiley-Liss, Inc. MICROSURGERY 22:304-310 2002)

Mice are popular animals for biomedical studies, but few skin flap models have been reported in them. To investigate the ischaemia/reperfusion phenomenon in skin flaps, we first investigated the vascular anatomy of murine dorsal skin and then designed a suitable murine dorsal skin flap model. In 120 mice, six distinct vascular patterns were identified, one being seen in 111 mice (93%). Based on this finding, in Part 2 of the study, 15 mice had flaps (4 x 4 cm) raised based on the two caudal vascular pedicles of the left and right deep circumflex iliac vessels as a bipedicled flap in which the mean (SD) survival was 96 (5)%. In a further 10 mice, flaps were raised based on a single pedicle, the left deep circumflex iliac vessel, as a monopedicled flap, in which the mean (SD) survival was 71 (12)%. The bipedicled flap model was then used to study ischaemia/reperfusion injury. Twenty flaps were subjected to eight hours of ischaemia and subsequent reperfusion, and their mean (SD) survival was 43 (26)%. Histological assessments were also carried out using neutrophil and leucocyte counts, and significant differences between groups were observed.

Amrinone is a selective phosphodiesterase III inhibitor that increases cyclic adenosine monophosphate by preventing its breakdown. It is effective in the treatment of congestive heart failure because of its ability to increase myocardial contractility and vascular smooth muscle relaxation. This study was designed to clarify the potential efficacy of amrinone in plastic surgery by clinically assessing its ability to enhance flap blood flow after reconstructive surgery and relieve intraoperative vasospasm. Its effects were compared with those of prostaglandin E1 and lidocaine, which are widely approved agents for improving the hemodynamics of flaps. In the first clinical study, the effects on flap blood flow after flap transfers were investigated. Twenty-six patients underwent reconstructive surgery with vascularized free or pedicled flaps. Blood flow was measured before and 60 minutes after intravenous infusion of lactated Ringer solution (control), amrinone (10 microg/kg/min), or prostaglandin E1 (10 ng/kg/min) using a laser Doppler flowmeter. In the second study, the effects on relief of vasospasm during operation were evaluated. The blood flow of 28 island flaps was measured by laser Doppler flowmetry immediately after flap elevation and 10 minutes after topical application of saline (control), amrinone (5 mg/ml), or lidocaine (10%) to the pedicle in an attempt to resolve the vasospasm. In both clinical studies, the effects of amrinone were statistically no less than those of prostaglandin E1 and lidocaine. The results show that amrinone positively influences the microcirculatory blood flow of transferred flaps and relieves intraoperative vasospasm in clinical cases. The present study suggests that amrinone could be useful for postoperative and intraoperative care in reconstructive surgery.

To clarify the transport of O(2) across the microvessels in skeletal muscle, we designed an intravital laser microscope that utilizes a phosphorescence quenching technique to determine both the microvascular and tissue PO(2). After we injected the phosphorescent probe into systemic blood, phosphorescence excited by a N(2)-dye pulse laser was detected with a photomultiplier over a 10 microm in diameter area. In vitro and in vivo calibrations confirmed that the present method is accurate for PO(2) measurements in the range of 7-90 Torr (r = 0.958) and has a rapid response time. This method was then used to measure the PO(2) of microvessels with different diameters (40-130 microm) and of interstitial spaces in rat cremaster muscle. These measurements showed a significant drop in PO(2) in the arterioles after branching (from 74.6 to 46.6 Torr) and the presence of a large PO(2) gradient at the blood-tissue interface of arterioles (15-20 Torr). These findings suggest that capillaries are not the sole source of oxygen supply to surrounding tissue.

Background: Amrinone, a selective phosphodiesterase III inhibitor, is an agent that possesses a combination of positive inotropic and vasodilating properties as a result of preventing the degradation of cAMP, and it has recently been licensed for the treatment of heart failure. The aim of this study was to investigate the potential therapeutic application of amrinone to resolve vasospasm, which is the major problem in reconstructive surgery. In this study its effect was compared with that of lidocaine, the most commonly used topical vasodilating agent clinically., Materials and Methods: The probe of an ultrasonic transit-time volume flowmeter was applied to the femoral artery of rats to measure blood flow. After a baseline recording was obtained, 0.03 ml of epinephrine was applied topically to induce vasospasm. The vessels were then immersed in 1 ml of amrinone (5 mg/ml), 10% lidocaine hydrochloride, or normal physiological saline solution for 1 min in an attempt to resolve the spasm. In another group of animals, no solution was used following administration of epinephrine to allow observation of spontaneous resolution of the vasospasm over time., Results: The results showed an essentially immediate spasm-resolving effect in both the amrinone group and the lidocaine group. The amrinone group showed a significantly greater degree of maximum increase in blood flow than the lidocaine group. The effect of lidocaine decreased with time, whereas amrinone had a more lasting effect., Conclusions: The findings suggest that amrinone could be used as an effective topical vasodilating agent to resolve vasospasm in reconstructive surgery., (Copyright 2000 Academic Press.)

Ingestion of caustic material often produces profound and irreversible pathologic changes that require reconstructive surgery of the organs damaged. This report describes the authors' successful experience with microsurgical techniques that allowed adequate reconstruction in three patients with cicatricial contracture of the oral cavity and esophagus following ingestion of caustic substances. All patients had attempted suicide by ingesting liquid alkali. Patients #1 and #2 complained of limited mouth opening and impaired tongue movement due to oral scar contracture. Contracture release in the first patient resulted in a defect from the anterior border of the mandible to the retromolar region. The defect was resurfaced with a 6 x 12 cm free forearm flap. Release of the scar contracture in the second patient resulted in a long, narrow, tortuous defect that was difficult to cover, even with a forearm flap, and a jejunal segment was microsurgically transferred as a patch graft to reconstruct the defect. Patient #3 had dysphagia due to stricture of the cervical portion of the esophagus. The defect after resection of the cervical portion was reconstructed by free jejunal interposition. Appropriately selected free-flap transfer in each case provided a satisfactory restoration of function of the oropharyngeal and digestive passages.

We investigated the acute effect of static magnetic fields of up to 8 T on skin blood flow and body temperature in anesthetized rats. These variables were measured prior to, during, and following exposure to a magnetic field in a superconducting magnet with a horizontal bore. The dorsal skin was transversely incised for 1 cm to make a subcutaneous pocket. Probes of a laser Doppler flowmeter and a thermistor were inserted into the pocket and positioned at mid-dorsum to measure skin blood flow and temperature. Another thermistor probe was put into the rectum to monitor rectal temperature. After baseline measurement outside the magnet, the rat was inserted into the bore for 20 min so that mid-dorsum was exactly positioned at the center, where the magnetic field was nearly homogeneous. Post-exposure changes were then recorded for 20 min outside the bore. Sham-exposed animals were submitted to exactly the same conditions, except that the superconducting magnet was not energized. Skin blood flow and temperature decreased significantly during magnetic field exposure and recovered after removal of the animal from the magnet. The rectal temperature showed a tendency to decrease while the animal was in the magnet. The microcirculatory and thermal reactions in the present study were consistent and agreed with some of the predictions based on mathematical simulations and model experiments., (Copyright 2000 Wiley-Liss, Inc.)

The clinical application of microvascular free-flap transfers in reconstructive surgery has expanded tremendously since their introduction. Difficult reconstruction in the head and neck region can now be accomplished in a one-stage procedure using these techniques. Free flaps such as rectus abdominis, forearm, and scapular flap have been used frequently in this region because of their many advantages. They have a long vascular pedicle of a large-caliber vessel with anatomic stability and have ample blood supply. It is easy to harvest, and donor site morbidity in negligible. However, further improvement and refinement of surgical procedures are required to obtain better functional results and increase patients' quality of life. In this article, we describe the most recent concepts and techniques in head and neck reconstruction.

Reconstruction of oral scar contracture is often a challenging problem due to the complex structures and functions of the oral cavity. This report describes the treatment of a patient who sustained extensive oral scar contracture following caustic liquid soda ingestion. Surgical release of the scar contracture formed an S-shaped, thin, long defect that was difficult to cover with a conventional flap or skin graft. A jejunal segment was transferred microsurgically as a patch to reconstruct the defect. It sustained a sufficient oral space to provide full opening of the mouth and good movement of the tongue. A free jejunal flap, used occasionally for reconstruction following oral cancer resection, has significant advantages for restoration of function after release of an oral scar contracture.

A new method that uses a prefabricated free jejunal transfer has been applied to three cancer patients with pharyngoesophageal defects with a high pharyngeal deficit extending up to the nasopharynx. In this method, the jejunum harvested in the usual manner is divided into two segments with a single vascular pedicle. Its distal segment is used to reconstruct the cervical esophagus, and its proximal segment is turned over to create a mucosal patch to cover the high pharyngeal defects. The two segments are then co-apted in a side-by-side anastomosis. The esophagus can be reconstructed in a naturally straight shape without a curved portion or blind loop formation, thus leading to good swallowing function. In our series, all grafts survived well and there was no complication directly related to jejunal transfer. All patients could tolerate a soft diet without difficulty. This method is easy to perform and applicable to any shape or size of very high pharyngeal defects that cannot be reconstructed properly by other methods. Although patients with an advanced hypopharyngeal cancer usually have a poor prognosis, this technique allows a better quality of life for a probable short life span.

A one-stage procedure for the reconstruction of a defect of the upper auricle is described. The anterior surface of a carved costal cartilage graft was covered with an anterosuperiorly based skin flap, and the posterior surface was covered by the superficial mastoid fascial flap and a skin graft. This method can be performed easily, without leaving any scar in the hair-bearing area or visible postauricular region, and can be applied to cases in which the condition of the margin scar of an auricular defect is poor.

Gel-forming dressings, which absorb the wound exudate to form a non-adherent gel, accelerate wound healing in a moist environment. The most commonly used of these dressings are calcium alginate and hydrocolloid membranes. This study was designed to evaluate the physical properties of these dressings, including fluid retaining ability, gel formation, and the dissolution process to clarify the mechanisms that promote healing. A simple immersion method was used for measurement. This technique was useful for the quantitative assessment of gel-forming dressings and may help to evaluate potential application of these dressings. A comparative analysis showed that alginate dressings remained gelled longer than hydrocolloid dressings. This result was consistent with previously reported clinical features of these dressings. The absence of calcium in wound fluid induced rapid resolution of alginate gel while the presence of a certain concentration of calcium prevented degradation of the gel for as long as one month.

The effect of chronic administration of the alpha 1 blocker prazosin on microvascular angiogenesis was studied in rabbit ear chamber to investigate the role of concomitant increase in flow-oriented wall shear stress in vascular remodeling during angiogenesis. Rabbits were treated with prazosin hydrochloride (50 mg/liter in water) orally after ear chambers were installed. The microcirculation in the chamber was observed and recorded from 4 to 23 postoperative day (POD) by an intravital videomicroscope. The total vascular area (TA) were quantified as a morphometric parameter. Changes in wall shear stress in venules (20-40 micron ID) were calculated from flow velocity, vessel diameter, and in vivo blood viscosity. TA was significantly increased in the prazosin-treated animals. The levels of shear stress, which was increased 1.43 times by prazosin on 9 POD, gradually decreased toward the control level on 13 POD and they almost coincided on 21 POD. These findings experimentally provided supporting evidence that shear stress is probably involved in the adaptive response as one of mechanical factors regulating vascular remodeling during angiogenesis., (Copyright 1998 Academic Press.)

Background: Amrinone, a selective phosphodiesterase (PDE) III inhibitor, is a newly developed agent that possesses a combination of positive inotropic and vasodilating properties as a result of preventing the degradation of cAMP and it has recently been licensed for treatment of heart failure alone. Amrinone is expected to be useful for the treatment not only of heart failure but also of peripheral circulatory disorders, including vascular disease, and for ischemic flaps, because it improves microcirculatory hemodynamics. To investigate potential therapeutic applications of amrinone, we evaluated its ability to improve microcirculatory hemodynamics and flap survival., Materials and Methods: The rat skinfold chamber technique was employed to quantify microcirculation directly in vivo. The improved survival area of random flaps in rats treated with amrinone was examined to assess therapeutic efficacy of this drug. Its effects were compared with those of prostaglandin E1 (PGE1), which has been widely approved as an agent for improving hemodynamics., Results: Microcirculatory blood flow and flap survival area were significantly increased in both amrinone- and PGE1-treated animals, compared to the saline-treated controls. The ameliorating effects of amrinone were comparable to those of PGE1., Conclusions: The results of this study suggest amrinone to be a potentially useful drug not only for treating heart failure but also for improving microcirculation in patients with vascular diseases and for postoperative care after reconstructive surgery.

Recent studies indicate that wall shear stress plays a significant role in the physiological adaptation of the vascular system. This study focused on the effect of sustained wall shear stress on wound-healing angiogenesis by exploring the morphologic and hemodynamic changes in developing microvessels in vivo through the tissue repair process. Rabbits were treated with the alpha 1 blocker prazosin (50 mg/L in water) orally from Day 0 to Day 23 after implantation of ear chambers to increase peripheral blood flow. The microvasculature in the chamber was recorded from Day 7 to Day 23 by using an intravital videomicroscope. The relative area of the chamber covered by vascularized tissue (%), the rate of ingrowth (mm2/day), the total vascular area (mm2), and the wall shear stress level (dyne/cm2) in venules (diameter in 20-40 microns) were quantified using a computerized image analysis system. The relative area increased significantly in the prazosin-treated animals from Days 7 to 19. The chamber of the treated group was completely covered with vascularized tissue earlier than that of the control group. The final total vascular area was larger by 21% in the treated group. The time course of shear stress in the treated group showed an initial elevation (1.44 times increase vs the control) followed by a gradual decrease toward the control level. These findings suggest that wound-healing angiogenesis may be partly involved in the adaptive response of microvasculature to shear stress.

A case of skin metastasis of adenocarcinoma on the back of a 69-year-old female was reported. The ultrasound appearance of the tumor indicated a malignant lesion prior to the detection of a primary lung carcinoma.

The combined loss of skin and tendons after avulsion or degloving injuries continues to be a challenging problem. A 51-year-old man sustained an extensive avulsion injury of the dorsal hand. He underwent reconstruction with a vascularized tendinocutaneous free flap transfer from the dorsum of the foot and was followed for over a year. The functional and aesthetic results were satisfactory.

Pseudocyst of the auricle is a rare, asymptomatic cystic swelling of the auricle resulting from accumulation of yellow viscous fluid with unknown cause. We herein report 3 such patients in whom biochemical study of the aspirated fluid revealed markedly elevated activity of lactate dehydrogenase (LDH) and a preponderance of LDH-4 and LDH-5. We postulate that pseudocyst formation is due to the disruption of the auricular cartilage and that LDH in the fluid is released from the auricular cartilage. This observation supports that the lesions represent a pattern of chondromalacia. It is hypothesized that the cause of such pseudocysts is repeated minor trauma.

A case of dermal duct tumor on the back of a 61-year-old male, representing a cystic lesion, is reported. Such cystic dermal duct tumors seem to be considered poroid hidradenomas according to the recently suggested classification of poromas. Poroid hidradenoma is rarely mentioned in the literature, and no description of its clinical features has yet been published. Carcinoembryonic antigen (CEA) immunostaining was positive in the tumor cells adjacent to the cystic space. We suppose that these CEA-positive cells were associated with cyst formation in our case.