Skin wound healing is a complex process involving many types of cells and molecules and often results in scar tissue formation in adult mammals. However, scarless healing occurs in foetal skin and minimal scars may occur after cutaneous healing in the adult with reduced inflammation. Alpha-melanocyte-stimulating hormone (α-MSH) is widely distributed within the central nervous system and in other body regions, such as the skin, and has strong anti-inflammatory activity. The aim in the present experiments was to learn whether intraperitoneal (i.p) injection of α-MSH just before skin wounds antagonize inflammation and improves skin wound healing in adult mice. C57BL/6 young adult mice received an i.p. injection of 1 mg/kg of α-MSH and, 30 min later, two circular through-and-through holes (6.5 mm diameter) were made in their dorsal skin under anaesthesia. Control mice were wounded after vehicle injection. The wound healing process was analysed macroscopically and microscopically at 3, 7, 40 and 60 days. Skin samples were fixed in formalin, embedded in paraffin, sectioned at 5 μm, stained with H&E or toluidine blue for cell analysis or Gomori's trichrome for extracellular matrix (ECM) analysis. Other samples were fixed in DMSO+methanol, embedded in paraplast and incubated with anti-CD45, antismooth muscle actin, anticollagen-I and anticollagen-III for immunofluorescence analysis. Alpha-MSH significantly reduced the number of leucocytes, mast cells and fibroblasts at 3 and 7 days after injury. On days 40 and 60, α-MSH reduced scar area and improved the organization of the collagen fibres indicating that it may direct the healing into a more-regenerative/less-scarring pathway.

Tissue injury in adult mammalian skin frequently results in scarring while fetal mammalian skin heals with complete regeneration. Inflammatory reactions are among the factors thought to impair regeneration. Previous studies have shown that the injection of an immunologically tolerated protein blocks immune responses to unrelated antigens and is also able to inhibit inflammation in mice. This phenomenon, which we refer to as the indirect effects of oral tolerance, does not require the simultaneous injection of the tolerated antigen and the second antigen, and also occurs when the two antigens are given by separate routes of immunization. Herein, we investigated whether the i.p. injection of an orally tolerated antigen (ovalbumin, OVA) would inhibit inflammatory reactions at an incisional lesion and influence healing of adult mouse skin. In OVA-tolerant mice, the injection of OVA minutes before wounding altered inflammation: it reduced the numbers of mast cells, neutrophils, and lymphocytes but increased the number of macrophages around the lesion area. Tolerant mice also showed fewer myofibroblasts and reduced scar area. Furthermore, tolerant mice displayed a pattern of extracellular matrix deposition similar to that observed in intact skin, plus characteristics of regeneration, such as an increased deposition of fibronectin and tenascin-C. These observations suggest that the indirect effects of oral tolerance can alter the process of wound healing in skin and reduce scar formation.

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Oral tolerance refers to the specific inhibition of immune responsiveness to T-cell-dependent antigens contacted through the oral route before parenteral immunization. Oral tolerance to one protein does not inhibit immune responses to other unrelated proteins, but parenteral injection of tolerated antigens plus adjuvant into tolerant, but not normal, mice inhibits immune responses to antigens injected concomitantly or soon thereafter. The inhibitory effect triggered by parenteral injection of tolerated proteins is known as bystander suppression or indirect effects of oral tolerance. Intraperitoneal injection of ovalbumin (OVA) plus alum adjuvant in OVA-tolerant mice soon before skin injury inhibits inflammation and improves cutaneous wound healing. However, as OVA is not a regular component of mouse chow, we tested whether indirect effects could be triggered by zein, the main protein of corn that is regularly present in mouse chow. We show that intraperitoneal injection of a single dose (10 μg) of zein plus alum adjuvant soon before skin injury in mice reduces leucocyte infiltration but increase the number of T cells and the expression of resistin-like molecule-α (a marker of alternatively activated macrophages) in the wound bed, increases the expression of transforming growth factor-β in the newly formed epidermis and reduces cutaneous scar formation. These results suggest that indirect effects of oral tolerance triggered by parenteral injection of regular dietary components may be further explored as one alternative way to promote scarless wound healing.

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A incidência de Infecções Sexualmente Transmissíveis (IST) é um problema de saúde pública mundial. Estatísticas apontam que 1/3 dos portadores de HIV/AIDS são jovens de 10 a 24 anos. Sendo estes os disseminadores de conhecimento para as gerações futuras, faz-se necessário investir em programas de educação sexual, visando à prevenção e melhora no quadro mundial de IST. Por meio da ação de extensão “Programa Jovem com Saúde: Universidade e escolas públicas na prevenção de IST”, este trabalho teve como objetivo levar informações a adolescentes do Ensino Médio de uma escola de São João del-Rei sobre as IST, gerar discussões visando estimular o pensamento crítico e a autonomia dos alunos acerca do tema e complementar a ação da escola na promoção de uma educação sexual de qualidade. Foram realizadas palestras e dinâmicas sobre IST, gravidez, métodos contraceptivos e sexo. As dinâmicas basearam-se em afirmativas que os adolescentes julgariam como corretas ou incorretas, prosseguidas por discussão. Os resultados mostraram um conhecimento superficial dos alunos sobre as doenças em questão, o que pode ser resultado do não aprofundamento do tema, associado ao estigma que o envolve. Conclui-se que investir em educação sexual de qualidade é o caminho para a solução deste problema.

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In the increasingly competitive hotel environment, decision-makers must consider the risks and benefits of remaining independent or affiliating with a brand or consortium. This research sought to understand the level of importance associated with a set of motivating factors considered by Portuguese four- and five-hoteliers as it relates to remaining independent or affiliating. The study results suggest that independent hoteliers rank control over decision making and shorter decision making as most important in remaining independent, and increased sales and more aggressive marketing as most important in the decision to affiliate. Affiliated hoteliers rank shorter decision making and absence of fees as most important in remaining independent, and increased sales, brand value, and more aggressive marketing as most important in the decision to affiliate. Interestingly, independence and freedom were considered less important in the decision to remain independent, by all respondents. We apply Hofstede’s cultural dimensions theory to explain some of the key findings.