Adenovirus-relaxin gene therapy for keloids: implication for reversing pathological fibrosis.

BACKGROUND: Keloids or hypertrophic scars are pathological proliferations of the dermal skin layer resulting from excessive collagen deposition. Because the hormone relaxin (RLX) inhibits collagen synthesis and expression in stimulated fibroblasts, an adenovirus expressing RLX (dE1-RGD/lacZ/RLX) was generated. OBJECTIVES: To investigate the effect of RLX-expressing adenovirus on expression of various extracellular matrix (ECM) components in primary keloid spheroids. METHODS: The expression levels of type I and III collagen, fibronectin and elastin were investigated by immunohistochemistry in primary keloid spheroids transduced with the RLX-expressing adenovirus. RESULTS: Immunohistochemical analysis showed that expression of major ECM components (e.g. type I and III collagen, elastin and fibronectin) was markedly reduced in primary keloid spheroids transduced with dE1-RGD/lacZ/RLX. CONCLUSIONS: These results suggest that the antifibrotic effect of RLX-expressing adenovirus may have therapeutic effects on keloids by reversing pathological fibrosis and preventing keloid recurrence after surgical excision.

Objective evaluation of treatment effects on port-wine stains using L*a*b* color coordinates.

Wide variations in port-wine stains and their responses to various therapies pose a need for the development of an objective method to evaluate the effects of treatment. Several techniques such as laser Doppler, reflectance spectrometry, and tristimulus colorimetry have been used to evaluate the color of port-wine stains, but these techniques are limited by cost, small test size area, and other factors. Therefore, we developed a simple and cost-effective method of evaluating treatment results on port-wine stains using the L*a*b* color coordinate system in combination with a personal computer. For 22 patients with port-wine stains, the slide photographs were digitized using a slide scanner. L*a*b* color differences of the normal control and port-wine stain sites were obtained before and after treatment, and treatment effect (percent) was calculated. By calculating each color difference between the lesion and normal skin both before and after treatment, problems arising from different illuminating conditions during photography were minimized. The results were compared with the visual evaluation conducted by three experienced plastic surgeons. The treatment effects analyzed by L*a*b* color coordinate ranged from 4 to 95 percent, with a mean of 48.1 percent, whereas treatment effects evaluated by the plastic surgeons ranged from 15 to 92 percent, with a mean of 51.1 percent. The subjective clinical grades correlated well with the treatment effects obtained by the proposed color analysis system (correlation coefficient, 0.89). The maximum difference in the effect of treatment for a patient evaluated by the three clinicians was up to 60 percent, which means that visual judgment is very subjective and variable. The color analysis system proposed as a result of this study is very easy, objective, quantitative, cost-effective, and can be useful for the evaluation of treatment effects on colored skin lesions such as port-wine stains.

Pulp reconstruction of fingers with very small sensate medial plantar free flap.

The essence in dealing with the pulp deficit accompanying fingertip injuries lies in functional restitution of the inherent skin texture and characteristics unique to that area and sufficient preservation of digital length, along with successful restoration of fine tactile sensation indispensable to delicate and skillful maneuvers. Among various techniques used to meet such demands, the very small sensate medial plantar free flap can be considered an excellent method in view of the skin texture that allows firm grasping, durability to friction rub, a cushion effect, and adequate sensation. Six cases of finger pulp reconstruction with the very small sensate medial plantar free flap are presented. At follow-up examination (an average follow-up of 24.3 months), the patients were evaluated clinically and neurologically. The operative procedures, advantages, and results in clinical cases are presented. Satisfactory results were obtained with sufficient preservation of digital length and good sensory recovery. No functional deficit was found at the donor site.

Art of replacing craniofacial bone defects.

In the history of medicine, many surgeons have been tried to reconstruct lost tissue and correct deformity, attempts to use implant materials have probably paralleled those involving autogenous tissue. Recently there has been an acceleration in the understanding of the requirements and potentials of implant materials caused by collaboration between material scientists, biomaterials engineers, clinicians, and clinical investigators. Alloplastic materials have become an essential part of reconstructing the function and contour of the craniofacial skeleton. Bone is a specialized form of connective tissue, which provides support, and protects vital and delicate organs. Bone is embryologically derived from mesenchymal tissue through membranous and endochondral ossification. In the clinical field, the need for bone graft has been increased due to trauma, tumor, craniosynostosis, and pure esthetic bone surgery. Various types of bone grafts have been used to repair craniofacial bone defects over many years, but the autogenous graft has many disadvantages, such as, limited donor sites, donor morbidity, pain, growth deformity and resorption. Many surgeons working in a number of centers around the world have created substitutes and simpler methods for bone replacement. As the alloplatic bone substitute has been advanced, many synthetic substitutes are replaced by bone in vivo over time. The ideal material should be cost effective, non-toxic, non-antigenic, non-carcinogenic, and inert in the body fluids, be easily shaped at the operating table, and maintain its desired form and consistency in situ. This article reviews several of the more commonly used materials for craniofacial reconstruction and summarizes their mechanical properties and clinical aspects.

Isolation and pure culture of microvascular endothelial cells from the fetal skin.

Microvascular endothelial cells were purely isolated from human fetal skin using magnetic particles. The principle of this technique is based on the selective binding of the lectin Ulex europaeus I (UEA I) to the endothelial cell surface via fucose residues. Initially UEA I was covalently bound to tosyl-activated magnetic polydisperse polymer particles (Dynabeads) and then the UEA I-coated beads were collected using a magnetic particle concentrator (MPC). Endothelial cells were isolated by extracting microvascular segments from trypsin-treated fetal skin tissue and were purified by sieving with nylon mesh and by 35% Percoll gradient centrifugation. For further purification, the obtained cells were incubated with UEA I-coated Dynabeads. The endothelial cells bound to the Dynabeads were collected using MPC. This is a simple and reproducible technique for isolating a pure population of microvascular endothelium from the fetal skin.

The fetal wound healing: a review.

Fetal wound healing has drawn the attention of many researchers from diverse background and specialties. Fetal wound healing is unique and differs from postnatal healing in that fetal skin wounds heal rapidly without scar formation. If the mechanism underlying such phenomenon can be elucidated, it will be serve as a significant milestone in the study of wound healing. Furthermore, the implications for therapeutic applications in wound management and in diseases where scarring is the basic pathogenetic mechanism would be immense. Rather than to list the results and conflicting data of numerous studies, this article hopes to provide a general overview of the recent developments.

A quantitative evaluation of pigmented skin lesions using the L*a*b* color coordinates.

The evaluation of pigmentary skin lesions by clinical doctors has been based on subjective and qualitative judgements. Observations have mostly relied on visual inspection, making the effects of treatment difficult to evaluate with any precision. For this reason there is a real need for an objective method to evaluate prognosis after treatment. Recent scientific measurements such as reflectance spectrophotometry and reflectance colorimetry have provided accurate quantitative color information about skin lesions, but these techniques are costly and difficult to apply in the clinical field. The purpose of this study was to develop a simple and cost-effective way of evaluating treatment results. We have developed a software program using the L*a*b* color coordinate system to quantify the effect of treatment and have successfully demonstrated its clinical usefulness. Our method compares the relative color difference between normal skin and skin lesions before and after treatment, instead of measuring the absolute color of skin lesions. The accuracy of our quantitative color analysis was confirmed by the simulated images of hemangioma and ota nevus. Clinical efficacy was also confirmed through a blind test involving 3 clinicians who were asked to grade the treatment effects of 13 cases of hemangioma and 7 cases of ota nevus. These subjective clinical grades correlated well with the treatment results obtained using the proposed color analysis system (Correlation coefficient = 0.84).

Comparative study on motility of the cultured fetal and neonatal dermal fibroblasts in extracellular matrix.

One of the differences between fetal and adult skin healing is the ability of fetal wounds heal without contraction and scar formation. Extracellular matrix (ECM) provides a substratum for cells adhesion, migration, and proliferation and can directly influence the form and function of cells. As motility is essential for many important biological events, including wound healing, inflammatory response, embryonic development, and tumor metastasis, this study was designed to compare the motilities cultured dermal fetal and neonatal fibroblasts in the extracellular matrix. The motility of cultured fetal and neonatal fibroblasts was compared using a video-microscopy system that was developed in combination with a self-designed CO2 mini-incubator. To determine migration speed, cells were viewed with a 4X phase-contrast lens and video recorded. Images were captured using a color CCD camera and saved in 8-bit full-color mode. We found that cultured fetal fibroblasts move faster than neonatal fibroblast on type I collagen (fetal fibroblast, 15.1 micrometer/hr; neonatal fibroblast, 13.7 micrometer/hr), and in fibronectin (fetal fibroblast, 13.2 micrometer/hr; neonatal fibroblast, 13.0 micrometer/hr) and hyaluronic acid (fetal fibroblast, 11 micrometer/hr; neonatal fibroblast, 9.8 micrometer/hr).

A noninvasive estimation of hypernasality using a linear predictive model.

The pronunciation of a speaker with a defective soft palate is marked by hypernasality and an operation may be necessary to repair the defective soft palate to reduce this hypernasality. An assessment of hypernasality is necessary to quantify the effect of the surgery. The current clinical methods for assessing hypernasality are uncomfortable or require expensive equipment. In this paper, a new quantitative method is proposed to estimate hypernasality. This method requires only a microphone and a personal computer equipped with a sound card. Zeros in the frequency response of the vocal tract system are one of the major characteristics of hypernasality. The proposed method made use of the fact that a linear predictive model with a typical order for the human vocal tract system is not accurate when the vocal tract system has zeros in its frequency response. Hypernasality was estimated by comparing the distance between the sequences of linear predictive cepstrum of low- and high-order linear predictive models. The proposed method provides a better correlation (0.58) with nasalance measured by a nasometer than Teager method (0.44) for all the data. Furthermore, the proposed method showed higher correlation of 0.84 than 0.71 of the Teager method for data with a nasalance higher than 35%. Since the proposed method needs only digitized speech data, it is much less invasive and provides an easy and cost-effective evaluation of hypernasality.