BACKGROUND -Several studies have been performed to understand the tissue repair process as well as the possible effects of laser therapy in wound healing. OBJECTIVES -To study the behavior of skin wounds induced in the dorsal region of Wistar rats (Rattus norvegicus), which were submitted to the low-intensity laser therapy at 3.8 J/cm 2 dosage, 15mW potency, during 15 seconds. MATERIAL AND METHODS -The animals (n=12) were divided into two groups -control and laser-treated. The latter comprised three applications (immediately after surgery, 48 hours and 7 days after induction of surgical wounds). Ten days after surgery samples of the wounds were collected and submitted to histopathological and histomorphometric studies. RESULTS -Neovascularization, fibroblast proliferation and reduced inflammatory infiltrate in surgical wound submitted to laser therapy were demonstrated. CONCLUSION -Taken together, the results suggest that low-intensity laser therapy is an effective method to modulate tissue repair, thus significantly contributing to a faster and more organized healing process.

Skin remodelling induced by MAL-PDT was demonstrated in photodamaged skin. Two sessions of MAL-PDT increases immunohistochemical expression of MMP-9 in the dermis at 3 months after treatment, and also of collagen type I.

SummarySplenectomy results in an increased risk of sepsis. The autogenous transplant of the spleen is an option for preserving splenic functions after total splenectomy. In this study, the capacity of animals undergoing autogenous spleen transplantation to respond to Staphylococcus aureus infection was investigated. BALB/c mice were divided into three groups: splenectomy followed by autotransplantation in the retroperitonium (AT), splenectomized only (SP) and operated non-splenectomized sham control (CT). Thirty days after surgery the mice were infected intravenously with S. aureus. Splenectomized mice had a higher number of colony-forming units (CFU) of S. aureus in liver and lungs in comparison with either AT or with CT mice (P < 0·05). Higher CFU numbers in lung of SP mice correlated with elevated production of interleukin-10 associated with a lower production of interferon-g and tumour necrosis factor-a. However, systemically, the level of tumour necrosis factor-a was higher in the SP group than in CT or AT. Lower titres of specific anti-S. aureus immunoglobulin (Ig)M and IgG1 were observed 6 days after infection in SP mice in comparison either with the AT or CT groups. Thus, splenectomy is detrimental to the immune response of BALB/c mice against infection by S. aureus which can be re-established by autogenous implantation of the spleen.

Metronidazole 4% solution at a dose of 50 mg/kg applied topically to wounds healing by secondary intention facilitates early peripheral epithelialization, does not interfere with wound contraction and delays the appearance of myofibroblasts.