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Dermis
Kinds of Dermis Selected AbstractsPheomelanin Production in the Epidermis from Newborn Agouti Mice is Induced by the Expression of the Agouti Gene in the DermisPIGMENT CELL & MELANOMA RESEARCH, Issue 5 2004Tomohisa Hirobe The present study was designed to clarify the role of the agouti gene in the regulation of the proliferation and differentiation of mouse epidermal melanocytes using serum-free primary culture of epidermal melanocytes from 0.5-d-old black (a/a; C57BL/10JHir) mice and congenic, agouti (A/A; C57BL/10JHir- A/A) mice. There was no significant difference in the proliferation or differentiation of melanocytes between a/a and A/A mice. However, the content of pheomelanin in culture media from A/A melanocytes was increased by l -tyrosine compared with a/a melanocytes. In addition, the content of the pheomelanin precursor, 5- S -cysteinyldopa, in culture media from A/A melanocytes was dramatically increased by l -tyrosine. Moreover, pheomelanin content in the epidermis from 3.5- and 5.5-d-old A/A mice was much higher than in a/a mice. Analysis of the A gene using reverse transcription-polymerase chain reaction revealed that cultured keratinocytes and melanocytes do not express the A gene. Moreover, the A gene was expressed in the A/A dermis of 0.5-, 3.5- and 5.5-d-old mice, but not in the a/a dermis nor in the A/A or a/a epidermis. These results suggest that A/A epidermal melanoblasts are influenced by the A gene from the dermis of neonatal mice, and are capable of synthesizing pheomelanin in the culture. Pheomelanin production in the epidermis from 3.5- and 5.5-d-old A/A mice may be induced by the expression of the agouti gene in the dermis. [source] The Use of Acellular Dermis in the Prevention of Frey's SyndromeTHE LARYNGOSCOPE, Issue 11 2001Satish Govindaraj MD Abstract Educational Objective At the conclusion of this presentation, the participant should be able to discuss the indications and advantages of using acellular dermis in the prevention of post-parotidectomy gustatory sweating (Frey's Syndrome). Introduction Gustatory sweating is a common postoperative problem and a challenge to treat. The purpose of this study was to evaluate the role of acellular dermis in preventing post-parotidectomy gustatory sweating. Methods Sixty-four patients were randomly assigned to two groups. Group I consisted of 32 patients who underwent a superficial lobe parotidectomy. Group II consisted of 32 patients who underwent a superficial lobe parotidectomy and underwent intraoperative placement of acellular dermis within the parotid bed, between the skin flap and the remaining parotid tissue. The implanted volume of acellular dermis was determined by the amount required to aesthetically restore lateral facial contour. All 64 patients were evaluated for gustatory sweating by identical phone and mail questionnaires. Thirty randomly chosen patients (group I = 15, group II = 15) were evaluated using a modified Minor's Starch-Iodine Test (MSIT). In all 30 patients, the MSIT was administered to both sides of the face. Results The responses to questionnaires (N = 64) demonstrated the subjective presence of gustatory sweating in 3 of 32 patients (9.3%) in group I, whereas group II demonstrated a subjective incidence in 1 of 32 patients (3.1%). The objective incidence determined by those who underwent the MSIT (n = 30) revealed a 40% (6) and 0% incidence of Frey's Syndrome in groups I and II, respectively. The complication rate in group I was 9% (3 seromas) and in group II it was 25% (7 seromas and 1 wound infection). Conclusions Acellular dermis appears to be an effective method for preventing post-parotidectomy gustatory sweating, despite its higher complication rate. [source] Tissue Engineered Artificial Skin Composed of Dermis and EpidermisARTIFICIAL ORGANS, Issue 1 2000Eun Kyung Yang Abstract: We made an artificial skin comprised of a stratified layer of keratinocytes and a dermal matrix with a type I collagen containing fibroblasts. In this work, we showed keratinocyte behavior under primary culture, gel contractions varying with concentration of collagen solution, and cell growth plots in the collagen gel. The optimum behavior of dermal equivalent could be obtained using 3.0 mg/ml collagen solution and attached gel culture. The attached gel culture had a jumping effect of growth factor on cell growth at the lag phase. To develop the artificial skin, 1× 105 cells/cm2 of keratinocytes were cultured on the dermal equivalent at air-liquid interface. Finally, to overcome the problem that artificial skin of collagen gel was torn easily during suturing of grafting, we prepared histocompatible collagen mesh and attached the mesh to the bottom of the gel. Cultured artificial skins were successfully grafted onto rats. [source] Application for regenerative medicine of epithelial cell culture-vistas of cultured epitheliumCONGENITAL ANOMALIES, Issue 3 2006Hajime Inoue ABSTRACT This review describes culture techniques for the epithelial system as well as trends in the clinical application of cultured keratinocytes in our department and the possibility of applying the techniques to other organs. Cultured epithelium and cultured dermis in particular have considerably preceded regeneration of other organs in the field of regenerative medicine. Since 1988 we have grafted cultured keratinocytes by the Rheinwald-Green modified method in at least 500 patients with large skin defects. As a result of the establishment of a culture technique for individual patients, it is now possible to prepare enough regenerated epithelium to cover the body surface area of as many as 10 adult patients in approximately three weeks after collecting 1 cm2 of skin, and then remaining cultured keratinocytes can be cryo-preserved for two-stage dermatoplasty at another site. This procedure makes it possible to avoid frequent skin collection from the same patient and thereby improves patients' quality of life and activities of daily living. On the other hand, to solve the problem of regenerated epithelium shrinking and problems with graft efficiency on dermis defect lesion, we have developed a proteinase-resistant regenerated dermis by mixing a certain protein with a fibrin scaffold. Recently we also took the initiative in grafting hybrid-type regenerated trachea in an animal experiment by using the epithelial and dermal cell culture technique, and some results of the graft were obtained. [source] Multiwavelength Laser Treatment of Venous LakesDERMATOLOGIC SURGERY, Issue 12 2009MÓNICA RONCERO MD BACKGROUND Venous lakes (VLs) are common benign ectasias in the upper dermis, usually observed in older people. Different treatment strategies have been described as useful, such as cryosurgery, excision, and various types of laser. OBJECTIVE We report our experiences using a multiwavelength laser, which has not been previously described. PATIENTS AND METHODS Thirty-nine VLs in 30 patients were treated. Treatment with 595-nm pulsed-dye laser was conducted at 20 ms and 10 J/cm2, followed by 1,064-nm neodymium-doped yttrium aluminum garnet laser at 20 ms and 70 J/cm2. RESULTS Complete resolution was observed in 38 lesions (95%). No complications after treatment were noted. One case developed a small scar. CONCLUSIONS Multiwavelentgh laser (595 nm; 1,064 nm) provides a safe, fast, and effective option in the treatment of VLs. [source] Does Imiquimod Histologically Rejuvenate Ultraviolet Radiation,Damaged Skin?DERMATOLOGIC SURGERY, Issue 12 2007KATHLEEN SMITH MD BACKGROUND Imiquimod (IMI) 5% is believed by some to result in an improved cosmetic appearance of chronically ultraviolet radiation (UV)-damaged skin. OBJECTIVE The objective was to determine what histologic and immunohistologic changes were present in actinically damaged skin after treatment with IMI. METHODS AND MATERIALS Pre- and posttherapy biopsies of 12 patients with histories of actinic keratoses were evaluated with routine histology and immunohistochemical stains including p53, p63, proliferating cell nuclear antigen (PCNA), c-kit, and Factor XIIIa. RESULTS After IMI therapy there was less compact hyperkeratosis, a more uniform rete ridge pattern with a more ordered proliferation of the epidermis, and a decrease in sun-damaged melanocytes. The papillary dermis showed a more uniform cellularity, and there was increased cellularity within the area of solar elastosis. After therapy, staining for p53, p63, and PCNA was decreased within the epidermis; staining for c-kit was decreased but more uniform in the basal cell; and Factor XIIIa expression was increased within the papillary dermis with a more ordered pattern of staining. CONCLUSION These morphologic and immunohistochemical patterns may explain some of the improvement in overall skin appearance after IMI therapy and may be related to the spectrum of signaling pathways induced by the imidazoquinolines. [source] Histometric and Histochemical Analysis of the Effect of Trichloroacetic Acid Concentration in the Chemical Reconstruction of Skin Scars MethodDERMATOLOGIC SURGERY, Issue 10 2006SUNG BIN CHO MD BACKGROUND Atrophic scars can be induced by various causes, including severely inflamed acne, chicken pox, and trauma. Many treatment modalities are used for reconstructing and improving the appearance of scars with various treatment results. OBJECTIVE A recent report shows the clinical efficacy of the chemical reconstruction of skin scars (CROSS) method, which consists of the focal application of trichloroacetic acid (TCA) in a higher concentration. Histometric analysis of the CROSS method, however, has not yet been established. METHODS In this study, five hairless mice were used to evaluate the effect of the CROSS method and to analyze the difference between the CROSS method and simple TCA application. RESULTS Similar histologic changes were observed in the two methods, including epidermal and dermal rejuvenation with new collagen deposition. These changes, however, were more prominent in the CROSS method,treated areas, particularly when 100% TCA was used. CONCLUSION The results of this study suggest that treatment of atrophic scars using the CROSS method is more effective than simple application of TCA in activating fibroblasts in the dermis and increasing the amount of collagen. [source] Nonablative Acne Scar Reduction after a Series of Treatments with a Short-Pulsed 1,064-nm Neodymium:YAG LaserDERMATOLOGIC SURGERY, Issue 8 2006GRAEME M. LIPPER MD BACKGROUND Effective treatment of facial acne scarring presents a major challenge. Nonablative lasers and radiofrequency devices work by thermally stimulating dermal collagen remodeling, thereby softening acne scars in a minimally invasive fashion. One such laser, a 1,064-nm short-pulsed Nd:YAG, uses rapidly scanned low-energy infrared pulses to heat the dermis selectively through the normal dermal microvasculature. OBJECTIVE In this pilot study, the safety and efficacy of a novel short-pulsed Nd:YAG laser were investigated for the treatment of moderate to severe facial acne scarring. MATERIALS AND METHODS Nine of 10 enrolled patients with moderate to severe facial acne scarring received eight sequential 1,064-nm Nd:YAG treatments (laser parameters 14 J/cm2, 0.3 milliseconds, 5-mm spot size, 7-Hz pulse rate, 2,000 pulses per side of face). Patients were graded for the presence and severity of three scar morphologies: superficial (rolling), medium-depth (boxcar), and deep (ice pick). Outcome measures included blinded evaluation of before and after photographs by three physician observers (scar severity score) and patient self-assessment. RESULTS Acne scarring improved in 100% of the nine patients completing the study. Scar severity scores improved by a mean of 29.36% (95% confidence interval, 16.93%,41.79%; p=.006); 89% of patients noted greater than 10% scar improvement. No treatment-related adverse events were seen. CONCLUSION Our findings support the use of a short-pulsed, low-fluence 1,064-nm Nd:YAG laser as a safe, effective treatment for facial acne scarring. Scar improvement was noted in all treated subjects with minimal discomfort and no downtime. This protocol appears to be most effective at reducing scar depth and softening scar contours. [source] Injection Necrosis of the Glabella: Protocol for Prevention and Treatment After Use of Dermal FillersDERMATOLOGIC SURGERY, Issue 2 2006ADRIENNE S. GLAICH MD BACKGROUND Injection of filler materials into the dermis is well tolerated with few mild and transient side effects. Injection necrosis is a rare but clinically important potential complication caused by interruption of the vascular supply to the area by compression, injury, and/or obstruction of the vessel(s). The glabella is a particular danger zone for injection necrosis regardless of the type of filler used. OBJECTIVE We recommend a protocol that may be used to help prevent and treat injection necrosis of the glabella after injection with dermal fillers. CONCLUSION Injection necrosis in the glabellar region may be prevented by a knowledge of the local anatomy and an understanding of its pathophysiology and treated by a suggested protocol. [source] Deep Phenol Peeling and Fat Injection: Treatment Option for Perioral Wrinkles in a Scleroderma PatientDERMATOLOGIC SURGERY, Issue 7 2005Yitzhack Ramon MD Background Scleroderma is characterized by abnormal growth of connective tissue, often manifested with hard and tight skin. The viscous properties of the skin are impaired, and the main histologic changes include a thicker dermis, absence of pilosebaceous units, and a decreased space between collagen bundles. Often these patients have wound healing problems. Objective The objective was to demonstrate a case of scleroderma that had deep phenol perioral peeling and fat injection into the lips. According to our bibliographic search, this is the first report in the English literature of using these modalities in scleroderma patients. Methods A 64-year-old woman suffering from scleroderma for more than 20 years came for improvement of her perioral appearance. We decided to manage her deep perioral wrinkles by deep peeling using the Baker formula and concomitantly to use autologous fat injection to augment her thin lips. Results The healing of our patient after these two interventions was uneventful, and satisfactory results have been obtained. Conclusion Based on our experience, this intervention may be suggested for patients suffering from scleroderma after a detailed explanation of the possible wound healing difficulties is provided to the patients. [source] Curettage prior to Mohs' Micrographic Surgery for Previously Biopsied Nonmelanoma Skin Cancers: What Are We Curetting?DERMATOLOGIC SURGERY, Issue 1 2005Comparative Study, Prospective, Retrospective Background Curettage prior to excision and Mohs' micrographic surgery for nonmelanoma skin cancer is performed based on the assumption that the curette will remove softer, more friable tumor-infiltrated dermis and leave structurally intact normal skin. This assumption, however, has not been objectively examined in the dermatologic surgery literature. Objective We performed a study to examine the ability of curettage to selectively remove and delineate nonmelanoma skin cancer prior to Mohs' micrographic surgery. Methods The study included 150 previously biopsied basal cell and squamous cell carcinomas less than 1.5 cm in size. We conducted (1) a retrospective study of 50 tumors curetted prior to Mohs' surgery by a surgeon who routinely curettes preoperatively; (2) a prospective study in which a surgeon who routinely does not curette preoperatively curetted 50 tumors prior to Mohs' surgery; and (3) a comparative historical group of 50 noncuretted tumors treated with Mohs' surgery by the latter surgeon. All curetted tissue was evaluated histologically. Results Only 50% of the curetted tissue demonstrated the presence of tumor in the curettings, but in 76% of these, the curette left residual tumor at the surgical margins. Of the other 50% in which the curette removed only non,cancer-containing skin, 34% had tumor present at the surgical margin. Overall, the curette removed tumor, leaving no residual tumor at the surgical margins in only 12% of lesions. Comparison with historical noncuretted tumors operated on by the same surgeon showed that curettage did not affect the mean number of stages or the proportion of tumors requiring more than one stage for histologic clearance. Conclusion Although curettage may be helpful in debulking friable skin prior to Mohs' micrographic surgery, it does not reliably delineate the extent of a tumor. MING H. JIH, MD, PHD, PAUL M. FRIEDMAN, MD, LEONARD H. GOLDBERG, MD, AND ARASH KIMYAI-ASADI, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Use of a Living Dermal Equivalent for a Refractory Abdominal Defect after Pediatric Multivisceral TransplantationDERMATOLOGIC SURGERY, Issue 9 2004Carlos A. Charles MD Background. Primary closure is not always possible after pediatric multivisceral transplantation. Reepithelialization may require extended periods of postoperative time, which can be associated with significant morbidity Objective. The objective was to accelerate secondary wound closure thereby minimizing infection or further complications in a pediatric multivisceral transplant patient. Methods. Five applications of human fibroblast-derived dermis (Dermagraft, Smith and Nephew) were applied to the postsurgical defect of a pediatric multivisceral transplant patient over the course of 8 months. Routine wound care and observation was performed between human fibroblast-derived dermis applications. Results. Human fibroblast-derived dermis stimulated healing and accelerated reepithelialization. Signs of clinical rejection or infection were not observed. Conclusion. Reepithelialization can be aided in the postoperative period in pediatric multivisceral transplant patients with human fibroblast-derived dermis, thereby helping to deter complications associated with secondary wound closure. We have illustrated the successful use of a human fibroblast-derived dermis as an adjunct for wound healing in a complicated surgical defect. [source] Dermoscopic Features of Mucinous Carcinoma of the SkinDERMATOLOGIC SURGERY, Issue 8 2004Rie Yoshida Background. Dermoscopic features of nonpigmented skin lesions are seldom reported; dermoscopy might be useful in speculating pathologic features in the upper dermis. Objective. The objective was to identify additional dermoscopic criteria. Methods. Dermoscopy of the mucinous carcinoma of the skin occurring on the cheek of a 69-year-old man was performed. Results. We have shown characteristic dermoscopic features of whitish network and light-brown globules and they correspond to the pathologic findings of fibrous septum and mucinous deposition, respectively. Discussion. Dermoscopic examination seemed useful as an adjunct to the diagnosis of this rare nonpigmented malignant neoplasm. [source] Ocular Melanoma Metastatic to Skin: The Value of HMB-45 StainingDERMATOLOGIC SURGERY, Issue 6 2004Robert A. Schwartz MD Background: Cutaneous metastatic disease is an important finding that may represent the first sign of systemic cancer, or, if already known, that may change tumor staging and thus dramatically altered therapeutic plans. Although cutaneous metastases are relatively frequent in patients with cutaneous melanoma, they are less so from ocular melanoma. Objective: To demonstrate the value of HMB-45, staining in the detection of ocular melanoma metastatic to skin. Methods: The immunohistochemical stain HMB-45 a monoclonal antibody directed against intact human melanoma cells, was employed on a skin biopsy specimen from a cutaneous tumor. Results: HMB-45 staining was positive in the atypical hyperchromatic cells of the deep dermis. Conclusion: HMB-45 may be of value in the detection of ocular melanoma metastatic to skin. Cutaneous metastatic disease is a somewhat common and extremely important diagnosis. Although cutaneous metastases from cutaneous melanoma are relatively frequent, those from ocular melanomas are less so. Use of histochemical staining, especially the HMB-45 stain, allows confirmation of the diagnosis. [source] Rapid Development of Keratoacanthomas After a Body PeelDERMATOLOGIC SURGERY, Issue 2 2003SueEllen Cox MD Resurfacing techniques have been traditionally limited to the face because of a lack of predictability and standardization for peeling nonfacial skin. There is a need for medical and surgical intervention for treating nonfacial skin that is actinically damaged. Medium-depth chemical peels (Jessner +35% trichloroacetic acid) remove the photodamaged epidermis to stimulate the production of new collagen in the dermis and remove lesions associated with facial actinic damage, including lentigines and actinic keratoses. Widespread actinic damage is common on the arms and chest. A 70% glycolic acid gel plus 40% trichloroacetic acid peel (Cook Body Peel) is a controlled peel that predictably enables peeling of nonfacial skin in a uniform and safe fashion with specific clinical endpoints. An unusual complication of this body peel is reported. [source] Gross and Microscopic Findings in Patients Submitted to Nonablative Full-Face Resurfacing Using Intense Pulsed Light: A Preliminary StudyDERMATOLOGIC SURGERY, Issue 8 2002Enrique Hernández-Pérez MD background. Intense pulsed light (IPL) is a noncoherent, nonlaser, filtered flashlamp emitting a broadband visible light that has been shown to be effective in photoepilation, as well as in a number of vascular and pigmented lesions of the skin. Their efficacy has also been reported recently in the treatment of photodamaged facial skin. In the last condition, however, there are few studies showing the clinical and microscopic changes produced by IPL. objective. To assess the gross and microscopic changes that occur in photodamaged skin submitted to nonablative full-face resurfacing (NAFFR) using IPL. methods. Five women were submitted to five NAFFR sessions using IPL, one every 2 weeks. Skin biopsies and photographs were taken on all of the patients before the first procedure and after the last one, as well as weekly clinical assessment. Data concerning skin features (wrinkles, oiliness, thickness, dilated pores, and general appearance) were all assessed. Microscopic improvement of the aging features in the epidermis and dermis were all assessed. For the statistical analysis a t test for small samples was used. results. All the patients showed clinical and microscopic improvement in every one of the parameters assessed. The t test for small samples showed a statistically significant difference (P < 0.01) in epidermal thickness. conclusion. Facial photodamage was clinically and microscopically improved using IPL. Use of IPL as a rejuvenating method seems to be promising, with minimal side effects, a wide safety margin, and minimal downtime. [source] Follicular Unit Extraction: Minimally Invasive Surgery for Hair TransplantationDERMATOLOGIC SURGERY, Issue 8 2002William R. Rassman MD background. Follicular Unit Transplantation (FUT) is performed using large numbers of naturally occuring individual follicular units obtained by single-strip harvesting and stereo-microscopic dissection. Donor wound scarring from strip excision, although an infrequent complication, still concerns enough patients that an alternative solution is warranted. objective. The purpose of this paper is to introduce Follicular Unit Extraction (The FOX Procedure), in which individual follicular units are removed directly from the donor region through very small punch excisions, and to describe a test (The FOX Test) that determines which patients are candidates for this procedure. This paper explores the nuances, limitations, and practical aspects of Follicular Unit Extraction (FUE). methods. FUE was performed using 1-mm punches to separate follicular units from the surrounding tissue down to the level of the mid dermis. This was followed by extraction of the follicular units with forceps. The FOX test was developed to determine which patients would be good candidates for the procedure. The test was performed on 200 patients. Representative patients who were FOX-positive and FOX-negative were studied histologically. results. The FOX Test can determine which patients are suitable candidates for FUE. Approximately 25% of the patients biopsied were ideal candidates for FUE and 35% of the patients biopsied were good candidates for extraction. conclusion. FUE is a minimally invasive approach to hair transplantation that obviates the need for a linear donor incision. This technique can serve as an important alternative to traditional hair transplantation in certain patients. [source] Resurfacing of Pitted Facial Acne Scars with a Long-Pulsed Er:YAG LaserDERMATOLOGIC SURGERY, Issue 2 2001Jeung-Tae Jeong MD Background. Conventional short-pulsed Er:YAG lasers show less effective hemostasis and weak photothermal damage on papillary dermis. Recently, newer long-pulsed Er:YAG laser systems has been developed. Objective. To evaluate the clinical and histologic effects of long-pulsed Er:YAG laser resurfacing for pitted facial acne scars. Methods. Thirty-five patients with pitted facial acne scars were treated with a long-pulsed Er:YAG laser. All patients had Fitzpatrick skin phototypes III,V. A pulsed Er:YAG laser with a 5 mm handpiece at a setting of 7.0,7.5 J/cm2 with a 10-msec pulse duration was used. The laser was fired at 5 Hz, with four to five passes. In 28 patients, the results of laser treatment were evaluated for the degree of clinical improvement, duration of erythema, pigmentary change, and any adverse events at 2 weeks, 1 month, and 3 months. In seven patients, skin biopsy specimens were obtained at the following intervals: immediately, 1 week, 2 weeks, 4 weeks, and 8 weeks postoperatively for histologic examination. Results. The results of long-pulsed Er:YAG laser resurfacing for pitted facial acne scars were excellent in 10 patients (36%), good in 16 patients (57%), and fair in 2 patients (7%). Erythema occurred in all patients after laser treatment and lasted longer than 3 months in 15 patients (54%). Postinflammatory hyperpigmentation occurred in 8 patients (29%). But the pigmentation faded or disappeared within 3 months. One patient (4%) experienced mild hypopigmentation. Pruritic symptoms that required medical intervention occurred in 16 patients (57%). Mild to moderate postoperative acne flare-up occurred in 8 patients (29%). No other adverse effects such as scarring, bacterial infection, or contact dermatitis were observed. Conclusion. In conclusion, resurfacing with a long-pulsed Er:YAG laser is a safe and very effective treatment modality for pitted facial acne scars. [source] Increased Glycosaminoglycans Production in Sclerosing Basal Cell Carcinoma-Derived Fibroblasts and Stimulation of Normal Skin Fibroblast Glycosaminoglycans Production by a Cytokine-Derived from Sclerosing Basal Cell CarcinomaDERMATOLOGIC SURGERY, Issue 11 2000Ronald L. Moy MD Sclerosing basal cell carcinoma (S-BCC) is characterized by an abundant stroma. There is evidence that some tumor cells secrete cytokines that are mitogenic for stromal fibroblasts (FBs). From this study we report increased glycosaminoglycan (GAG) production by cultures of S-BCC FBs in comparison to cultures of nodular BCC (N-BCC) FBs and normal skin FBs. GAG production was measured by cetylpyridinium chloride precipitation of incorporated [3H]-glucosamine. The sclerosing BCC FBs demonstrated a significant increase in production of GAG over control FBs (P < .001) and over N-BCC FBs (P < .001). Values reported as a mean percentage ± SEM for GAG production by S-BCC over control normal skin FBs are 359 ± 28 and over N-BCC FBs are 266 ± 27. In additional experiments, cell extract dilutions from S-BCC tumor, normal dermis, and normal epidermis were incubated with cultures of normal skin FBs. S-BCC-conditioned media was also incubated with normal FBs and GAG production was measured. For both S-BCC extracts and conditioned media, a dose response curve was established showing increased GAG production by normal FBs in relation to increasing the concentration of S-BCC extract or conditioned media. When S-BCC extract was added to normal FBs there was increased GAG production in comparison to normal FBs incubated with dermal or epidermal extracts (P < .001) for both. Two growth factors, transforming growth factor-, (TGF-,) and platelet-derived growth factor (PDGF), already known to be mitogenic for FBs, were incubated with N-BCC and normal FBs in an effort to elucidate the potential cytokine(s) released by S-BCC, causing increased GAG production by surrounding FBs. Neither of these cytokines proved to be effective in promoting a significant increase in GAG production. Our findings support the hypothesis that BCCs release factors that alter stromal FB production of GAG. [source] Approach to procedures in neonatesDERMATOLOGIC THERAPY, Issue 2 2005Valerie B. Lyon ABSTRACT:, Physical constraints and metabolic differences in neonates require that special attention is given to performing procedures in this patient group. Neonates have a thinner dermis and a greater surface-to-weight ratio, allowing for easier invasion through the skin barrier. The enzymes for metabolism of agents and defense against organisms inside the body are not fully developed in infants. Very premature neonates also have less circulating albumin, making the effective concentration of circulating agent even greater. The infant is prone to unanticipated movement during procedures, such as rolling on the procedure table. The neonatal period is the most common time period for malformations to become manifest on the skin, and invasion of some of these lesions can produce morbidity. These and other factors affect the choice of the type of procedure used, the timing for intervention, and the approach to intervention in this age group. This article reviews the important considerations for approaching procedures and offers suggestions for safe and effective methods of reliably producing the intended outcome. [source] Embryonic dermal condensation and adult dermal papilla induce hair follicles in adult glabrous epidermis through different mechanismsDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2006Mutsumi Inamatsu Hair induction in the adult glabrous epidermis by the embryonic dermis was compared with that by the adult dermis. Recombinant skin, composed of the adult sole epidermis and the embryonic dermis containing dermal condensations (DC), was transplanted onto the back of nude mice. The epidermis of transplants formed hairs. Histology on the induction process demonstrated the formation of placode-like tissues, indicating that the transplant produces hair follicles through a mechanism similar to that underlying hair follicle development in the embryonic skin. An isolated adult rat sole skin piece, inserted with either an aggregate of cultured dermal papilla (DP) cells or an intact DP between its epidermis and dermis, was similarly transplanted. The transplant produced hair follicles. Histology showed that the epidermis in both cases surrounded the aggregates of DP cells. The epidermis never formed placode-like tissues. Thus, it was concluded that the adult epidermal cells recapitulate the embryonic process of hair follicle development when exposed to DC, whereas they get directly into the anagen of the hair cycle when exposed to DP. The expression pattern of Edar and Shh genes, and P-cadherin protein during the hair follicle development in the two types of transplants supported the above conclusion. [source] Dorsal versus ventral scales and the dorsoventral patterning of chick foot epidermisDEVELOPMENTAL DYNAMICS, Issue 3 2004Fabrice Prin Abstract The dorsal and ventral scales of the chick foot can be distinguished morphologically and molecularly: the dorsal oblong overlapping scuta expressing both , and , keratins, and the ventral roundish nonprotruding reticula expressing only , keratins. The question arises how En-1 and Lmx1, whose role in dorsoventral limb patterning has been well established, can affect skin morphogenesis, which occurs 8 to 12 days later. Forced expression of En-1 or of Lmx1 in the hindlimb have, respectively, as expected, a ventralizing or a dorsalizing effect on skin, leading to the formation of either reticula-type or scuta-type scales on both faces. In both cases, however, the scales are abnormal and even glabrous skin without any scales at all may form. The normal inductive interactions between dermis and epidermis are disturbed after En-1 or Lmx1 misexpression. Effectively, while Lmx1 endows the dermal precursors of the ventral region with scuta inducing ability, En-1 blocks the competence of the dorsal epidermis to build scuta. Developmental Dynamics 229:564,578, 2004. © 2004 Wiley-Liss, Inc. [source] Differentiation of the epidermis of scutes in embryos and juveniles of the tortoise Testudo hermanni with emphasis on beta-keratinizationACTA ZOOLOGICA, Issue 3 2005L. Alibardi Abstract The sequence of differentiation of the epidermis of scutes during embryogenesis in the tortoise Testudo hermanni was studied using autoradiography, electron microscopy and immunocytochemistry. The study was mainly conducted on the epidermis of the carapace, plastron and nail. Epidermal differentiation resembles that described for other reptiles, and the embryonic epidermis is composed of numerous cell layers. In the early stages of differentiation of the carapacial ridge, cytoplasmic blebs of epidermal cells are in direct contact with the extracellular matrix and mesenchymal cells. The influence of the dermis on the formation of the beta-layer is discussed. The dermis becomes rich in collagen bundles at later stages of development. The embryonic epidermis is formed by a flat periderm and four to six layers of subperidermal cells, storing 40,70-nm-thick coarse filaments that may represent interkeratin or matrix material. Beta-keratin is associated with the coarse filaments, suggesting that the protein may be polymerized on their surface. The presence of beta-keratin in embryonic epidermis suggests that this keratin might have been produced at the beginning of chelonian evolution. The embryonic epidermis of the scutes is lost around hatching and leaves underneath the definitive corneous beta-layer. Beneath the embryonic epidermis, cells that accumulate typical large bundles of beta-keratin appear at stage 23 and at hatching a compact beta-layer is present. The differentiation of these cells shows the progressive replacement of alpha-keratin bundles with bundles immunolabelled for beta-keratin. The nucleus is degraded and electron-dense nuclear material mixes with beta-keratin. In general, changes in tortoise skin when approaching terrestrial life resemble those of other reptiles. Lepidosaurian reptiles form an embryonic shedding layer and crocodilians have a thin embryonic epidermis that is rapidly lost near hacthing. Chelonians have a thicker embryonic epidermis that accumulates beta-keratin, a protein later used to make a thick corneous layer. [source] Effect of intravenous lidocaine administration on laminar inflammation in the black walnut extract model of laminitisEQUINE VETERINARY JOURNAL, Issue 3 2010J. M. WILLIAMS Summary Reasons for performing study: Laminitis is a serious complication of horses suffering from sepsis/endotoxaemia-related events. Laminitis in horses and organ injury in human sepsis are both reported to involve inflammatory injury to the laminae/organs including early activation of endothelium and leucocytes leading to emigration of neutrophils into the tissue interstitium. In the black walnut extract (BWE) model, systemic inflammatory events coincide with marked increase in laminar mRNA concentrations of inflammatory genes including proinflammatory cytokines (i.e. IL-1,, IL-6), COX-2, chemokines (i.e. IL-8) and endothelial adhesion molecules (i.e. ICAM-1 and E-selectin). In models of human sepsis, i.v. lidocaine has been reported to decrease leucocyte and endothelial activation, and the expression of proinflammatory cytokines and chemokines. Objectives: To evaluate the effect of i.v. lidocaine therapy on the inflammatory processes documented to occur in the BWE model of laminitis. Methods: Twelve horses were administered BWE and treated immediately with either lidocaine (1.3 mg/kg bwt bolus, followed by 0.05 mg/kg bwt/min CRI, n = 6) or saline (n = 6) for 10 h. At 10 h post BWE administration, laminar samples were obtained under general anaesthesia for assessment of proinflammatory gene expression (using RT-qPCR) and leucocyte emigration (via CD13 immunohistochemistry). At 0, 3 and 10 h post BWE administration, skin samples were obtained for assessment of leucocyte emigration (via calprotectin immunohistochemistry). Results: No significant differences between groups were noted for inflammatory gene mRNA concentrations (IL-1,, IL-6, IL-8, COX-2) or for number of leucocytes present within the laminar interstitium or skin dermis. Increased (P<0.05) laminar E-selectin mRNA concentrations were present in the LD group (vs. SAL group). Conclusions: Continuous administration of i.v. lidocaine does not inhibit inflammatory events in either the laminae or skin in the horse administered black walnut extract. Potential relevance: This work questions the use of continuous i.v. administration of lidocaine as an effective anti-inflammatory therapy for systemic inflammation. [source] A two-step model for Langerhans cell migration to skin-draining LNEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 11 2008Eduardo J. Villablanca Abstract Although the role of Langerhans cells (LC) in skin immune responses is still a matter of debate, it is known that LC require the chemokine receptor CCR7 for migrating to skin-draining LN. A report in the current issue of the European Journal of Immunology unfolds some of the intricacies of LC migration, showing that LC need CXCR4, but not CCR7, for their migration from the epidermis to the dermis. Thus, LC migration to skin-draining LN occurs in two distinct phases: a first step from the epidermis to the dermis regulated by CXCR4 and a second CCR7-dependent step from the dermis to LN. Here we discuss the potential implications of this new two-step LC migration paradigm. [source] Cover Picture , Eur.EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2006The cover picture shows the localisation of the mannose receptor (MR) and collagen IV in a transverse section of the mouse dermis. Cells expressing the MR (red) are located alongside collagen IV fibres (green). This picture is taken from the article by Martinez-Pomares et al. (pp 1074,1082) in which the authors demonstrate that the murine MR can recognize collagen independently of carbohydrates and that the MR is also responsible for collagen internalisation by macrophages in vitro. [source] Absence of lymphatic vessels in human dental pulp: a morphological studyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2010Renato Gerli Gerli R, Secciani I, Sozio F, Rossi A, Weber E, Lorenzini G. Absence of lymphatic vessels in human dental pulp: a morphological study. Eur J Oral Sci 2010; 118: 110,117. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci Few and controversial data are available in the literature regarding the presence of lymphatic vessels in the human dental pulp. The present study was designed to examine morphologically the existence of a lymph drainage system in human dental pulp. Human dental pulp and skin sections were immunohistochemically stained with specific antibodies for lymphatic endothelium (D2-40, LYVE-1, VEGFR-3 [vascular endothelial growth factor receptor-3], and Prox-1), with the pan-endothelial markers CD31 and von Willebrand factor (vWF), and with the blood-specific marker CD34. Several blood vessels were identified in human pulps and skin. Lymphatic vessels were found in all human skin samples but in none of the pulps examined. Western blotting performed on human dermis and on pulps treated with collagenase (to remove odontoblasts) confirmed these results. Transmission electron microscopy indicated that vessels which, by light microscopy, appeared to be initial lymphatic vessels had no anchoring filaments or discontinuous basement membrane, both of which are typical ultrastructural characteristics of lymphatic vessels. These results suggest that under normal conditions human dental pulp does not contain true lymphatic vessels. The various theories about dental pulp interstitial fluid circulation should be revised accordingly. [source] Generality of vertebrate developmental patterns: evidence for a dermomyotome in fishEVOLUTION AND DEVELOPMENT, Issue 1 2006S. H. Devoto SUMMARY The somitic compartment that gives rise to trunk muscle and dermis in amniotes is an epithelial sheet on the external surface of the somite, and is known as the dermomyotome. However, despite its central role in the development of the trunk and limbs, the evolutionary history of the dermomyotome and its role in nonamniotes is poorly understood. We have tested whether a tissue with the morphological and molecular characteristics of a dermomyotome exists in nonamniotes. We show that representatives of the agnathans and of all major clades of gnathostomes each have a layer of cells on the surface of the somite, external to the embryonic myotome. These external cells do not show any signs of terminal myogenic or dermogenic differentiation. Moreover, in the embryos of bony fishes as diverse as sturgeons (Chondrostei) and zebrafish (Teleostei) this layer of cells expresses the pax3 and pax7 genes that mark myogenic precursors. Some of the pax7- expressing cells also express the differentiation-promoting myogenic regulatory factor Myogenin and appear to enter into the myotome. We therefore suggest that the dermomyotome is an ancient and conserved structure that evolved prior to the last common ancestor of all vertebrates. The identification of a dermomyotome in fish makes it possible to apply the powerful cellular and genetic approaches available in zebrafish to the understanding of this key developmental structure. [source] Comprehensive survey of carapacial ridge-specific genes in turtle implies co-option of some regulatory genes in carapace evolutionEVOLUTION AND DEVELOPMENT, Issue 1 2005Shigehiro Kuraku Summary The turtle shell is an evolutionary novelty in which the developmental pattern of the ribs is radically modified. In contrast to those of other amniotes, turtle ribs grow laterally into the dorsal dermis to form a carapace. The lateral margin of carapacial primordium is called the carapacial ridge (CR), and is thought to play an essential role in carapace patterning. To reveal the developmental mechanisms underlying this structure, we systematically screened for genes expressed specifically in the CR of the Chinese soft-shelled turtle, Pelodiscus sinensis, using microbead-based differential cDNA analysis and real-time reverse transcription-polymerase chain reaction. We identified orthologs of Sp5, cellular retinoic acid-binding protein-I (CRABP-I), adenomatous polyposis coli down-regulated 1 (APCDD1), and lymphoid enhancer-binding factor-1 (LEF-1). Although these genes are conserved throughout the major vertebrate lineages, comparison of their expression patterns with those in chicken and mouse indicated that these genes have acquired de novo expression in the CR in the turtle lineage. In association with the expression of LEF-1, the nuclear localization of ,-catenin protein was detected in the CR ectoderm, suggesting that the canonical Wnt signaling triggers carapace development. These findings indicate that the acquisition of the turtle shell did not involve the creation of novel genes, but was based on the co-option of pre-existing genes. [source] Why do melanomas get so dark?EXPERIMENTAL DERMATOLOGY, Issue 11 2009Rossitza Lazova Abstract:, Cutaneous malignant melanomas often exhibit pigmented regions that are darker than the surrounding skin. While melanoma cells are the original source of the melanin, keratinocytes and melanophages also contribute to the tumor colour because they contain melanin obtained from melanoma cells. However, little is known of the origin of darkly pigmented melanoma cells or of the molecular pathways regulating their melanin production. Here we discuss observations that dark melanoma cells emerge from within populations of melanoma in situ and that, in addition to producing abundant dark pigment, they appear to be undergoing autophagy. Moreover, autophagy appears to be a common trait of invasive melanoma cells in the dermis. The underlying cause of this phenomenon may stem from aberrant production of glycosylation structures known as ,1,6-branched oligosaccharides. Our studies of dark cutaneous melanomas were prompted by analyses of experimental mouse macrophage-melanoma hybrids fused in the laboratory. Like melanoma cells in cutaneous malignant melanoma, experimental hybrids also displayed abundant dark pigment and autophagy, and had high levels of ,1,6-branched oligosaccharides. Whether or not darkly pigmented malignant melanoma cells originate from fusion with macrophages in vivo remains to be determined. In any event, pigmentation in melanoma, long considered as a secondary aspect of the malignancy, may be a visible warning that the cells have gained competence for invasion and metastasis. [source] | |||||||||||||||||||