Zinc sulphate administered by transdermal iontophoresis improves breaking strength of surgical wounds in skin of alloxan-induced diabetic rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Continuous Electrical Current and Zinc Sulphate Administered by Transdermal Iontophoresis Improves Skin Healing in Diabetic Rats Induced by Alloxan: Morphological and Ultrastructural Analysis

Purpose. Evaluated the effects of continuous electrical current (CEC) or zinc administrated by transdermal iontophoresis (Zn+TDI). Methods. 120 male Wistar rats were submitted to an incision surgery at the anterior region of abdomen and distributed into 6 experimental groups with 40 animals: 3 diabetic groups and 3 normal groups, untreated and treated with CEC alone or with Zn+TDI. Each group was further divided into 4 subgroups with 10 rats each to be evaluated on the 4th, 7th, 14th, and 21st day after surgery. In each period, clinical and laboratory parameters from the animals were analyzed. Results. The analysis by optical and scanning electron microscopy showed a delay in the phases of wound healing in diabetic rats without treatment in all periods of the experiment; breaking strength (BS) was significantly reduced in skin scars of untreated diabetic rats when compared to other groups. In contrast, BS in skin scars of nondiabetic groups and diabetic rats treated with Zn+TDI showed significant increase in those, besides not presenting delayed healing. Conclusion. Electrical stimulation of surgical wounds used alone or in association with zinc by TDI is able to consistently improve the morphological and ultrastructural changes observed in the healing of diabetic animals.

Efficacy of low-level laser therapy on scar tissue

Background: Physiotherapy has a very important role in the maintenance of the integumentary system integrity. There is very few evidence in humans. Nevertheless, there are some studies about tissue regeneration using low-level laser therapy (LLLT). Aim: To analyze the effectiveness of LLLT on scar tissue. Methods: Seventeen volunteers were stratified by age of their scars, and then randomly assigned to an experimental group (EG) — n = 9 – and a placebo group (PG) – n = 8. Fifteen sessions were conducted to both the groups thrice a week. However, in the PG, the laser device was switched off. Scars’ thickness, length, width, macroscopic aspect, pain threshold, pain perception, and itching were measured. Results: After 5 weeks, there were no statistically significant differences in any variable between both the groups. However, analyzing independently each group, EG showed a significant improvement in macroscopic aspect (p = 0.003) using LLLT. Taking into account the scars’ age, LLLT showed a tendency to decrease older scars’ thickness in EG. Conclusion: The intervention with LLLT appears to have a positive effect on the macroscopic scars’ appearance, and on old scars’ thickness, in the studied sample. However, it cannot be said for sure that LLLT has influence on scar tissue.

An outbreak of human Leishmania (Viannia) braziliensis infection

The occurence of acute cutaneous leishmaniasis among inhabitants of 10 farms within 10 Km of the hamlet of Corte de Pedra, Bahia, Brazil was studied prospectively from 1984-l989. A mean population of 1,056 inhabitants living in 146 houses were visited every 6 months and the number of sKin ulcers recorded. A leishmanin skin test survey was done people with suggestive skin scars or active disease in l984. The incidence of skin ulcers due to Leishmania (Viannia) brasiliensis (Vlb) reached 83/1,000 inhabitants but declined sharply in the subsequent 2 years. Retrospective data shows that leishamiasis is a sporadic endemic disease. Although the reasons for this epidemic are unclear some possible aetiological factors are discussed.

Aplicação de danos mecânicos em abacates e seus efeitos na qualidade dos frutos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pentoxifylline modifies three-dimensional collagen lattice model contraction and expression of collagen types I and III by human fibroblasts derived from post-burn hypertrophic scars and from normal skin

Fibroblasts are thought to be partially responsible for the persisting contractile forces that result in burn contractures. Using a monolayer cell culture and fibroblast populated collagen lattice (FPCL) three-dimensional model we subjected hypertrophic scar and non-cicatricial fibroblasts to the antifibrogenic agent pentoxifylline (PTF - 1 mg/mL) in order to reduce proliferation, collagen types I and III synthesis and model contraction. Fibroblasts were isolated from post-burn hypertrophic scars (HSHF) and non-scarred skin (NHF). Cells were grown in monolayers or incorporated into FPCL`s and exposed to PTF. In monolayer, cell number proliferation was reduced (46.35% in HSHF group and 37.73% in NHF group, p < 0.0001). PTF selectively inhibited collagen III synthesis in the HSHF group while inhibition was more evident to type I collagen synthesis in the NHF group. PTF also reduced contraction in both (HSHF and NHF) FPCL. (C) 2009 Elsevier Ltd and ISBI. All rights reserved.

Intralesional pentoxifylline as an adjuvant treatment for perioral post-burn hypertrophic scars

Pentoxifylline (PTF), a methylxanthine derivative, has therapeutic use as an antifibrotic agent. In vitro, PTF inhibits the production of collagen and reduces the proliferation of fibroblasts in hypertrophic scars. This study aimed to evaluate changes in the elasticity of hypertrophic scars in the peribuccal area in burned patients, who presented with mouth-opening limitation. Eighteen patients were divided into two groups. The case group (n = 10) was treated with PTF 1 mg ml(-1), while in the control group (n = 8) no treatment was performed. Measurements of mouth opening (lip-to-lip and tooth-to-tooth distances in mm) were taken, before and after five therapeutic sessions with pentoxifylline with weekly intervals. The variations of these measures (Delta%) were calculated and submitted to statistical analyses. There was a significant improvement in the opening of the mouth, in vermilion distance (V = 3.20 mm) as much as the dental distance (DD = 4.19 mm) in the treated group, than in the control group. It was noted that pentoxifylline increases the elasticity of hypertrophic scars in the perioral area. (C) 2009 Elsevier Ltd and ISBI. All rights reserved.

Fractional Photothermolysis for the Treatment of Hypertrophic Scars: Clinical Experience of Eight Cases

Hypertrophic scars are common problems and represent a challenging condition to treat. Fractional photothermolysis has been effective at resurfacing photodamaged skin, acne scars, and atrophic scars, but there are few reports on its use for hypertrophic scars. To evaluate the safety and efficacy of 1,550-nm erbium-doped fiber laser treatment of hypertrophic scars in eight patients. Eight patients (skin phototypes II-IV) with hypertrophic scars received monthly treatments with a 1,550-nm erbium-doped fiber laser. Energy settings ranged from 35 to 50 mJ, and eight to 10 passes were applied with treatment levels 6 to 8. An independent physician evaluator assessed the treatment response by comparing pre- and posttreatment clinical photographs using a quartile grading scale (grade 1, <= 25%=minimal to no improvement; grade 2, 26-50%=moderate improvement; grade 3, 51-75%=marked improvement; grade 4, > 75%=near total improvement. At four weeks after the last treatment session, a mean grade of 2.4 was achieved based on an independent physician`s clinical assessment. Improvement in pigmentation occurred in all hyperpigmented scars. Hypertrophic scars can be effectively and safely improved with 1,550-nm erbium-doped fiber laser treatment. The authors have indicated no significant interest with commercial supporters.

EPIDEMIOLOGICAL SURVEY ON CANINE POPULATION WITH THE USE OF IMMUNOLEISH SKIN TEST IN ENDEMIC AREAS OF HUMAN AMERICAN CUTANEOUS LEISHMANIASIS IN THE STATE OF RIO DE JANEIRO, BRAZIL

A survey for canine tegumentary leishmaniasis (CTL) has been carried out between 1986 and 1993 in seven endemic localities for American cutaneous leishmaniasis in the State of Rio de Janeiro. 270 dogs have been examined for their clinical aspects, the development of delayed hypersensitivity (DHS) with Immunoleish antigen and with immunofluorescent antibody research of IgG (IF). 28.2% of them had ulcer lesions and 3.3% had scars. The lesions consisted of single (39.5%) and mucocutaneous lesions (31.6%), multiple cutaneous (25.0%) and mucocutaneous lesions associated with cutaneous ulcers (4.0%). Twelve (15.8%) isolates from biopsies were analyzed by zimodeme and schizodeme and identified as L. (V.) braziliensis. The overall prevalence of canine infection that was evaluated with the skin test was of 40.5% and with IF it was of 25.5%. Both tests showed a high positive rate with relation to the animals with mucosal lesions, as in the case of human mucocutaneous leishmaniasis. The comparison of the two tests showed the skin test to have a better performance although there was no statistical difference (p>0.05) between them. The proportional sensitivity and specificity was of 84.0% and 74.0%, respectively. The Immunoleish skin test and IF are useful tools to be employed in CTL field epidemiological surveys.

Results of a combination of bleomycin and triamcinolone acetonide in the treatment of keloids and hypertrophic scars.

While treatment of keloids and hypertrophic scars normally shows modest results, we found that treatment with bleomycin was more promising. The present study was divided into two parts. In the first part the aim was to show the results using a combination of bleomycin and triamcinolone acetonide per cm2 (BTA). In the second part the objective was to determine the response to both drugs in large keloids that were divided into 1 cm2 squares, treating each square with the dose previously used. In the first part of the study, the clinical response of 37 keloids ranging from 0.3 to 1.8 cm2 treated with BTA were followed up over a period of 1- 2 years. 0.375 IU bleomycin and 4 mg triamcinolone acetonide were injected every 3 months. In the second part of the study we reviewed the clinical response in six patients with large keloids. The monthly dose administered never exceeded 3 IU of bleomycin. The first study showed 36 keloids (97.29%) softening after the first dose. In the second study, 5 showed different responses (the response was complete in the four smaller keloids). The largest keloid needed 9 doses to achieve an improvement of 70%. In conclusion, combined treatment with 0.375 IU of bleomycin and 4mg of triamcinolone acetonide to 1 cm2 was considered to be an acceptable procedure for the treatment of keloids. The best results were obtained in keloids over 1 cm2 or when divided into 1 cm2 square areas. Larger series need to be performed in order to confirm these results..

An individualized approach to abdominoplasty in the presence of bilateral subcostal scars after open gastric bypass.

BACKGROUND: Patients requiring surgical skin excision after massive weight loss are challenging and require an individualized approach. The characteristic abdominal deformity includes a draping apron of panniculus, occasionally associated with previous transverse surgical scars from open gastric bypass surgery in the upper abdomen, which compromise blood supply of the abdominal skin. METHODS: We propose four different surgical techniques for safe abdominal body contouring in the presence of such scars: (1) a limited abdominoplasty of the lower abdomen is performed, and then contouring is completed by a reversed abdominoplasty with scar positioning in the submammary folds; (2) a one-stage procedure characterized by skin resection in the upper and lower abdomen, in which blood supply of the skin island between the submammary and suprapubic incisions is ensured by periumbilical perforators; (3) a perforator-sparing abdominoplasty with selective dissection of periumbilical abdominal wall perforators to secure flap blood supply and allow complete flap undermining up to the xyphoid process; (4) for patients with extensive excess skin, a modified Fleur-de-Lys abdominoplasty performed in such a way that the old transverse scar is transformed into a vertical scar. RESULTS: The treatment of four exemplary patients is described. All techniques yielded good esthetic and functional results through preservation of abdominal blood supply. CONCLUSION: Through an individualized approach, adequate abdominal body contouring can be performed safely, even in the presence of transverse surgical scars in the upper abdomen.

Normal skin and hypertrophic scar fibroblasts differentially regulate collagen and fibronectin expression as well as mitochondrial membrane potential in response to basic fibroblast growth factor

Basic fibroblast growth factor (bFGF) regulates skin wound healing; however, the underlying mechanism remains to be defined. In the present study, we determined the effects of bFGF on the regulation of cell growth as well as collagen and fibronectin expression in fibroblasts from normal human skin and from hypertrophic scars. We then explored the involvement of mitochondria in mediating bFGF-inducedeffects on the fibroblasts. We isolated and cultivated normal and hypertrophic scar fibroblasts from tissue biopsies of patients who underwent plastic surgery for repairing hypertrophic scars. The fibroblasts were then treated with different concentrations of bFGF (ranging from 0.1 to 1000 ng/mL). The growth of hypertrophic scar fibroblasts became slower with selective inhibition of type I collagen production after exposure to bFGF. However, type III collagen expression was affected in both normal and hypertrophic scar fibroblasts. Moreover, fibronectin expression in the normal fibroblasts was up-regulated after bFGF treatment. bFGF (1000 ng/mL) also induced mitochondrial depolarization in hypertrophic scar fibroblasts (P < 0.01). The cellular ATP level decreased in hypertrophic scar fibroblasts (P < 0.05), while it increased in the normal fibroblasts following treatment with bFGF (P < 0.01). These data suggest that bFGF has differential effects and mechanisms on fibroblasts of the normal skin and hypertrophic scars, indicating that bFGF may play a role in the early phase of skin wound healing and post-burn scar formation.

Effect of a calcium-channel blocker (verapamil) on the morphology, cytoskeleton and collagenase activity of human skin fibroblasts

The effects of verapamil modulating collagen biosynthesis have prompted us to study the role of this drug in cultured fibroblasts. In this article, we describe the effects of verapamil on fibroblast behaviour, with special emphasis to phenotypic modifications, reorganisation of actin filaments and secretion of MMP1. Human dermal fibroblasts treated with 50-mu M verapamil changed their normal spindle-shaped morphology to stellate. Treated cells showed discrete reorganisation of actin filaments, as revealed by fluorescein isothiocyanate (FITC)-phalloidin staining and confocal microscopy. We hypothesised that these effects would be associated to lower levels of cytosolic Ca(2+). Indeed, short time loading with calcium green confirmed that verapamil-treated fibroblasts exhibited lower intracellular calcium levels compared to controls. We also observed that verapamil increases the secretion of MMP1 in cultured fibroblasts, as demonstrated by zymography, specific substrate assays and immunoblot. The morphological alterations induced by verapamil are neither cytotoxic nor associated with other dramatic cytoskeleton alterations. Thus we may conclude that this drug enhances collagenase secretion and does not disrupt the major tracks necessary to deliver these enzymes in the extracellular space. The present results suggested that verapamil could be used at physiological levels to enhance collagen I breakdown, and maybe considered a potential candidate for intralesional therapy of wound healing and fibrocontractive diseases. (C) 2010 Elsevier Ltd and ISBI. All rights reserved.

Prognostic factors for lymph node metastasis from advanced squamous cell carcinoma of the skin of the trunk and extremities

Abstract Background Squamous cell carcinoma (SCC) of the skin of the trunk and extremities may present lymph node metastasis with difficult disease control and poor survival. The purpose of this study was to identify risk factors for lymph node metastasis and outcome. Patients/Methods Retrospective review of 57 patients with locally advanced SCC of the trunk and extremities was performed and several clinical variables including age, gender, ethnicity, previously injured skin (burns, scars, ulcers and others), patient origin (rural or urban), anatomic site and treatment were studied. Results Fifteen patients presented with previous skin lesions. Thirty-six were classified as T3 tumors and 21 as T4; 46 were N0, and 11, N1. Eleven N0 patients presented lymph node metastasis during follow up. Univariate analysis identified previous skin lesions (ulcers and scars) as risk factor for lymph node metastasis (p = 0.047). Better survival was demonstrated for T3 (p = 0.018) classification. N0 patients who presented lymph node metastasis during follow up (submitted to lymphadenectomy) had similar survival to patients without lymph node recurrence (p = 0.219). Conclusion Local advanced tumors are at risk of lymph node metastasis. Increased risk is associated to previous lesions at tumor site. T4 classification have worse prognosis. Lymph node recurrences in N0 patients, once treated, did not affect survival. For these patients, we propose close follow up and prompt treatment of lymph node metastasis. These results do not support indication for elective lymphadenectomy or sentinel node mapping. Further prospective studies must address this issue.

Low temperatures reduce skin healing in the Jacaré do Pantanal (Caiman yacare, Daudin 1802)

Studies of skin wound healing in crocodilians are necessary given the frequent occurrence of cannibalism in intensive farming systems. Air temperature affects tissue recovery because crocodilians are ectothermic. Therefore, the kinetics of skin wound healing in Caiman yacare were examined at temperatures of 33°C and 23°C. Sixteen caiman were selected and divided into two groups of eight maintained at 23°C or 33°C. The studied individuals' scars were photographed after 1, 2, 3, 7, 15 and 30 days of the experimental conditions, and samples were collected for histological processing after 3, 7, 15 and 30 days. Macroscopically, the blood clot (heterophilic granuloma) noticeably remained in place covering the wound longer for the caiman kept at 23°C. Microscopically, the temperature of 23°C slowed epidermal migration and skin repair. Comparatively, new blood vessels, labeled using von Willebrand factor (vWF) antibody staining, were more frequently found in the scars of the 33°C group. The collagen fibers in the dermis were denser in the 33°C treatment. Considering the delayed healing at 23°C, producers are recommended to keep wounded animals at 33°C, especially when tanks are cold, to enable rapid wound closure and better repair of collagen fibers because such lesions tend to compromise the use of their skin as leather.