Thesis (doctoral)--Karolinska Institutet, Stockholm, 1994. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (M.S.)--University of Alabama at Birmingham, 2006. / Description based on contents viewed Jan. 29, 2007; title from title screen. Includes bibliographical references (p. 51-54).

Thesis (doctoral)--Karolinska Institutet, Stockholm, 1994. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Chronic non-healing wounds commonly present in patients with diabetes. These wounds are characterised by elevated numbers of immature leukocytes and M1 macrophages and reduced numbers of endothelial cells and M2 macrophages, impairing wound healing resolution. Topical treatment of murine diabetic wounds with a Hoxa3 gene expression vector redresses the balance of inflammatory and pro-healing cells within the lesion, reducing excessive inflammation and rescuing the wound healing phenotype. In this thesis I present experiments to further understanding of how diabetes alters the macrophage phenotype and how this may cause the decreased endothelial cell and M2 macrophage numbers in the diabetic wound. In vitro culture was used to characterize the intrinsic changes of diabetic macrophages isolated from the environmental effects of the diabetic wound milieu. These same systems were used to develop a cell culture system for the promotion of monocytic to endothelial transdifferentiation. Finally the in vitro macrophage culture system was used to assess the effects of Hoxa3 treatment upon diabetic macrophages and how Hoxa3 transcriptional activity in macrophages may contribute to the restoration of wound healing. In vitro cultured diabetic macrophages were observed to raise an increased response to classical and alternative activation signals that may contribute to the excessive inflammatory state of diabetic cutaneous wounds. Treatment of these macrophages for four days with a Hoxa3 conditioned medium protein transduction system upregulated the expression of the plasminogen activator urokinase receptor gene Plaur and enhanced the expression of macrophage maturation markers. These macrophages also exhibit an enhanced response to classical activation stimuli, a reduced alternative activation response. In an in vitro neovascularisation assay Hoxa3 treated macrophages inhibit vessel growth. These effects of Hoxa3 treatment of diabetic macrophages are unexpected based on the rescue of the inflammatory phenotype with Hoxa3 treatment of diabetic wounds. Non-diabetic macrophages were also treated for four days with a Hoxa3 conditioned medium and exhibited upregulation of macrophage maturation markers. These macrophages showed no difference in activation state polarisation compared to macrophages grown in a control conditioned medium but did upregulate activation markers in unstimulated cells. This may be indicative of a priming for response to low levels of activation stimuli. The Hoxa3 treated non-diabetic cells also promoted the formation of vessel networks in a neovascularisation co-culture assay, possibly through the promotion of angiogenesis. These results suggest that diabetes directly effects the maturation and inflammatory phenotype of macrophages and that Hoxa3 treatment rescues the impaired maturation phenotype and may stimulate macrophage populations to a pro-angiogenic state.

Estrogen is an important regulator and promoter of epithelial wound healing. This is facilitated by increased keratinocyte and fibroblast migration and proliferation, as well as promotion of angiogenesis, matrix deposition and inflammatory response dampening. The potential to target this pathway for therapeutics is highlighted by observations that post-menopausal women on hormone replacement therapy have a significantly lower incidence of venous ulcers. Previous work from this laboratory identified four SNPs (single nucleotide polymorphisms) in the 5’UTR of estrogen receptor beta (ERβ) gene that are associated with venous ulcer predisposition. Disease association is further supported by the identification of ERβ as the main conduit of the beneficial effects of estrogen signalling on wound healing. SNP’s of the 5’UTR can affect transcriptional expression through the modification of transcription factor binding sites, epigenetic modifications and translational efficiency via mRNA localisation and secondary structure alterations. To investigate the possible biological function of these SNPs, we have developed disease relevant cell based assays where primary keratinocyte and fibroblast cells were selected harbouring disease-associated SNPs. We demonstrate that the presence of venous ulcer-associated ERβ SNPs reduced the expression of ERβ in skin cells and reduced their migration and proliferative capabilities. Evidence gathered here suggests that ERβ expression is curtailed by a change in transcription factor binding, likely facilitated by the change in nucleotide sequence brought about by the rs2987983 SNP. Further, we demonstrate that SNP-induced changes in fibroblast expression of growth factors and inflammatory mediators can hinder keratinocyte migration and induce a pro-inflammatory phenotype in human monocytes. Lastly, RNAseq analysis of keratinocytes reveals a SNP-dependant gene expression profile that is detrimental to wound healing. This work provides the first evidence of a direct functional link between venous ulcer-associated ERβ SNPs and dysfunctional wound healing. Investigating ERβ SNPs has provided insight into novel mechanisms of estrogen signalling that can be applied for therapeutic development to treat venous ulcers.

Wounds heal better in skin with terminal hair follicles (large and pigmented) as opposed to those with vellus hair follicles (small and unpigmented), while dermal fibroblasts from different anatomical regions also exhibit phenotypical differences. Tissue repair requires a tight control of cell proliferation, migration and apoptosis, and recent studies have shown the importance of inhibitors of apoptosis proteins (IAPs), which are proteins that prevent the process of apoptosis via their interaction with caspase molecules in wound healing. Oestrogens improve the rate and quality of wound healing, but their relationship with IAPs in human skin has not been studied. Therefore, terminal (scalp) and vellus (facial) hair bearing skin from the same donor was compared in situ and matching primary cultures of dermal fibroblasts were established from terminal (DF(T)) and vellus (DF(V)) hair bearing skin. Using immunofluorescent staining, the expression of IAPs and their antagonists was compared at different stages of the hair cycle following depilation using a murine model and then in terminal and vellus hair bearing human skin. The size and granularity of matching DF(T) and DF(V) cultures was compared by FACS analysis and mRNA and protein expression of Apollon, cIAP2, NAIP and XIAP and their antagonists DIABLO and Xaf1 analysed by qRT-PCR and immunocytochemistry in unwounded and mechanically wounded fibroblast cultures. Differences in proliferation, migration, viability and caspase 3 activity in the presence of 17β-oestradiol and changes in mRNA expression of the oestrogen receptors (GPR30, ERα and ERβ) were compared between the two cell types. IAP protein expression was generally found higher during mid anagen of the hair cycle in murine skin and hair follicles. Overall, expression was slightly higher in human terminal hair bearing skin compared to corresponding vellus hair bearing skin. IAP protein expression was similar in unwounded DF(T) and DF(V) cells with the exception of Apollon which was higher in DF(V) cells. With the exception of XIAP and its direct antagonist Xaf1, mRNA expression was higher in DF(V) cells compared to corresponding DF(T) cells. FACS analysis demonstrated that DF(V) cells were more granular than matching DF(T) cells and proliferated faster. 17β-oestradiol accelerated migration of DF(T) cells only. Mechanical wounding decreased XIAP mRNA in DF(T) and increased it in DF(V) cells, while simultaneously decreasing Xaf1 expression. In unwounded cells, 17β-oestradiol stimulated the expression of XIAP mRNA in both DF(T) and DF(V) cells, but in scratched monolayers, while it also increased expression in DF(T) cells it decreased it in DF(V) cells. A XIAP inhibitor reduced cell viability in both DF(T) and DF(V) cells, which was rescued by 17β-oestradiol in unwounded and mechanically wounded DF(T) cells, but only in unwounded DF(V) cells. 17β-oestradiol decreased caspase 3 activity in the presence of a XIAP inhibitor only in DF(T) cells. These results demonstrate significant differences between dermal fibroblasts cultured from terminal and vellus hair bearing skin of the same individual. The correlation between an increase in XIAP in response to 17β-oestradiol and a higher number of viable cells, along with a reduction in caspase 3 activity suggests that the protective effect of 17β-oestradiol may be modulated via the regulation of XIAP. Further elucidation of these different signalling pathways in dermal fibroblasts from hair bearing skin may lead to improved therapies for chronic non-healing wounds, particularly in postmenopausal females.

Fibroblast growth factors (FGFs), encompasses a family of 22 related polypeptide. There are 18 different biologically active FGF proteins. They influence a wide array of biological and physiological responses such as migration, proliferation, tissue homeostasis, and wound healing. Most FGF are secreted and bind to heparin sulphate binding proteins (HPSG) in the extra cellular matrix (ECM). FGF-binding protein (FGF-BP) is a chaperon protein that binds to FGF releasing from the ECM and chaperoning it to bind to FGF receptors (FGFRs). FGFR dimerize when bound to FGF and starts series of a signal cascade that ultimately leads to the activation of MAPK. FGF2 and FGF4 are selected from the pool of 18 different FGF to be studied in this investigation. Both FGF2 and FGF4 have been reported to be critical for development during embryogenesis. De-regulation of these proteins could lead to various pathologies including different types of cancers. Hence we attempt to investigate the cellular and molecular role of these proteins and their implication on cells in an attempt to set up a foundational understanding for further studies that will include FGF-BPs and FGFRs. To do so, we used HUVECs to examine FGF2 and FGF4 activity through Western Blot analysis. We also investigated their effect on migration using the ECIS Migration Assays, on wound healing by the ECIS Wound Healing Assays and captured wound healing images through Incucyte. Data from these experiments indicated that both, FGF2 and FGF4, have a role in cellular migration and wound healing. They also show they have a dose response on these cells. As a result, we can use these models to further investigate FGF2 and FGF4 modulation by FGF-BP1 and FGF-BP3 and the affects cellular response.

86f. / Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-23T13:59:20Z No. of bitstreams: 1 Tese - Antonio Marcio.pdf: 4443227 bytes, checksum: 11ef696551c6a19fa5033123778b8ab6 (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-08T11:46:43Z (GMT) No. of bitstreams: 1 Tese - Antonio Marcio.pdf: 4443227 bytes, checksum: 11ef696551c6a19fa5033123778b8ab6 (MD5) / Made available in DSpace on 2013-05-08T11:46:43Z (GMT). No. of bitstreams: 1 Tese - Antonio Marcio.pdf: 4443227 bytes, checksum: 11ef696551c6a19fa5033123778b8ab6 (MD5) Previous issue date: 2008 / O reparo tecidual inicia-se com a inflamação e tem continuidade com a presença de células secretoras e contráteis. Intervenções terapêuticas, como a fototerapia e a dexametasona, podem interferir neste processo biológico. Este trabalho teve o objetivo de avaliar a influencia destes dois agentes sobre o processo inflamatório e cicatricial. Foram realizadas feridas cutâneas padronizadas em 80 ratos, wistar, distribuídos em quatro grupos. O grupo controle isento de terapêutica. O grupo laser com a aplicação da radiação do laser diodo de AsGaAl, 9mW, l670nm, 0,031W/cm2 e 4J/cm2, em dose única após a cirurgia. O grupo dexametasona submetido à administração de 2mg/kg deste medicamento 1 hora antes da cirurgia e o grupo com associação de ambas as terapias submetido aos mesmos parâmetros descritos anteriormente. Após a morte dos animais o tecido foi corado com HE e avaliou-se edema, células polimorfonucleares e mononucleares. Com o sírius vermelho analisouse a matriz de colágeno. Foram utilizadas também a imuno-histoquímica e microscopia eletrônica de transmissão para avaliar os miofibroblastos. As mudanças nos achados das variáveis foram analisadas de forma semiquantitativa. Os resultados demonstraram que o laser e a dexametasona atuaram de forma semelhantes atenuando a inflamação aguda. A síntese de colágeno e a expressão de miofibroblastos foi mais intensa no grupo laser, do que no grupo dexametasona com diferenças estatisticamente significativas em alguns períodos (p 0,005). Na associação das terapias, a expressão do colágeno e de células actino- e desmino positivas foram menos expressivas do que o grupo tratado apenas com o laser. Assim, o laser foi eficiente em reduzir o edema e as células polimorfonucleares e acelerar o reparo tecidual, agindo como um bioestimulador, mesmo na presença da dexametasona. / Salvador

The aim of this study is the production of a nanofibrous electroactive mat and the investigation of its potential use in tissue engineering, and more specifically for wound dressing purposes. The limitations regarding electrospinnability of the conducting polymer will be identified and addressed and the factors related to its biological properties will be evaluated. To this end, conducting polymer, polyaniline (PANI) was chosen as the electroactive component and blend electrospinning was identified as the most suitable method to produce continuous nanofibres containing PANI. Various biocompatible polymers and solvent systems were investigated for their suitability to assist in electrospinning and PEO (polyethylene oxide) and CH (chitosan) were chosen as carrier polymers for blend electrospinning of PANI. Consequently, CSA (Camphor-10-sulfonic acid (β)) doped PANI/PEO and CSA doped PANI/CH conducting nanofibrous mats were produced by electrospinning. The electrospinning windows for both blends were determined by using full factorial experimental designs. The combined effects of the humidity, voltage and flow rate on the fibre morphology and diameter were examined for both blends, demonstrating that the ambient humidity is the critical factor affecting the electrospinning process and determining the electrospinning window for a conducting polymer. Low humidity favors the formation of defect free fibres while high humidity either hinders fibre formation or causes the formation of defects on the fibres. In the case of PANI/PEO blends, different levels of PANI doping were investigated, and high level of doping with CSA was found to lead to the formation of crystalline structures. Data fitting was used to explore the behavior of conducting polymers using the case of PANI/PEO electrospinning and very good agreement between experimental and theoretical predictions was obtained for only a limited range of experimental conditions, whereas deviation was observed for all other sets of conditions. In the case of PANI/CH, the effect of different ratios of conducting polymer in the blend (0:1, 1:3, 3:5 and 1:1) was examined, as for the electrospinnability, resulting 3 nanofibrous morphology, mat contact angle, electrical conductivity, antibacterial activity and cellular biocompatibility. The incorporation of PANI in the electrospinning blend, affected the electrospinnability of the solution, making it more susceptible to RH deviations, and contributed to the decrease of nanofibre diameter. Higher PANI content was found to result in more hydrophobic and more conducting mats. The method that was used to stabilize the PANI/CH mats was also found to affect antibacterial activity and conductivity. The produced blend mats, exhibited antibacterial activity which was higher against Gram positive B. subtilis and lower against gram negative E. coli. The cellular biocompatibility was assessed with human osteoblasts and fibroblasts, in terms of cell proliferation rate as well as cell attachment and morphology. Cells of both cell lines adhered well and showed good growth rates on nanofibrous substrates of all blend ratios when compared to standard tissue culture plastic. Finally, amongst the PANI containing mats, the one of 1:3 PANI:CH ratio, was identified as the best to support osteoblast and fibroblast cell proliferation when compared to the pure chitosan.

Made available in DSpace on 2015-12-10T14:22:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-28. Added 1 bitstream(s) on 2015-12-10T14:29:06Z : No. of bitstreams: 1 000855344.pdf: 2800080 bytes, checksum: 79f362b62618513eb3e196fe52ffff6b (MD5) / A enxertia cutânea é uma técnica cirúrgica simples e bastante útil para o reparo de feridas, principalmente nas quais existe dificuldade da aplicação do fechamento primário, ou de outras técnicas reconstrutivas. Entretanto, para a sobrevivência do enxerto, é necessário que o leito da ferida esteja saudável e com a presença de um tecido de granulação exuberante. O objetivo deste trabalho foi avaliar a aplicação da membrana amniótica e da laserterapia como potenciais estimulantes da cicatrização em enxertos aplicados em feridas sem tecido de granulação. Para isso, foram utilizados 42 coelhos divididos em quatro grupos de tratamento, grupo controle (GC), grupo membrana (GM), grupo laser (GL) e grupo membrana e laser (GML), submetidos a avaliações macro e microscópicas dos enxertos. Na avaliação macroscópica foi possível notar que os pacientes dos grupos onde a membrana amniótica foi utilizada com o intuito de estimular a reepitelização (GM e GML) apresentaram acentuada reação inflamatória, falha de integração do enxerto e consequente necrose do mesmo. Já os pacientes do grupo GL apresentaram melhor aspecto do enxerto no último dia de avaliação. Na análise microscópica, observou-se intensa integração do enxerto à derme, reepitelização acentuada e escassas células inflamatórias no local do enxerto nos pacientes do grupo GL. O oposto foi observado nos pacientes dos grupos GM e GML, onde aparentemente a presença da membrana amniótica induziu resposta inflamatória bastante consistente na região adjacente à membrana e ao enxerto, resultando em rejeição da membrana. Por último, a formação de colágeno não se correlaciona com outros fatores como inflamação e necrose, em nenhum dos grupos de tratamento. Desta forma, é possível afirmar que a laserterapia mostrou ser efetiva, contribuindo para o processo cicatricial e integração do enxerto. Já a membrana amniótica canina não deve ser... / Skin grafting is a simple surgical technique and useful to repair wounds, especially those where there is a difficulty to apply primary closure skin or other reconstructive techniques. However, for the graft survival it is necessary that the healthy wound bed and the presence of an exuberant granulation tissue. This study aimed to evaluate the application of amniotic membrane and laser therapy as potential stimulating healing in grafts applied in wounds without granulation tissue. For this, we used 42 rabbits divided into four treatment groups, control group (CG), membrane group (MG), laser group (LG) and membrane and laser group (MLG), submitted to macroscopic and microscopic evaluation. The macroscopic examination was possible to note that the patients of the groups where the amniotic membrane was used in order to stimulate re-epithelialization (MG and MLG) presented evidences associated with severe inflammatory reaction, graft integration failure and consequent necrosis. In LG patients apparently had the best aspect of the graft in the last valuation date. On the microscopic examination, there was intense integration of the graft to the dermis, high reepithelialization level and scarce inflammatory cells in the graft site of LG group patients. The opposite was observed in patients in the MG and MLG groups, where apparently the presence of amniotic membrane seems to have induced very consistent inflammatory response in the region adjacent to the membrane and the graft, evincing that there was a rejection of the membrane. Finally, the collagen formation does not correlated with other factors such as inflammation and necrosis in any of the treatment groups. We can conclude that laser therapy was effective, contributing to the healing process and integration of the graft. Thus, the canine amniotic membrane should not be used for this purpose because it causes intense inflammatory reaction besides to avoid graft nutrition