The effects of the antifibrotic drug Halofuginone hydrobromide (Halo) on muscle function, regeneration and cardiorespiratory function were studied using mdx mice. It was hypothesized that Halo treatment would resolve pre-established fibrosis and prevent collagen deposits, improving muscle and cardio-respiratory function. Mice 8-9 mos were treated with saline or Halo for 5 (n = 4/group), 10 (n = 5/group) and 12 weeks (n = 4-5/group). Muscle strength and endurance, respiration and muscle susceptibility to damage were assessed. Tissues were collected from all mice. Additional mice were treated for 10 wks (3-4 wks n = 9-10/group; 8-9 mos n = 8-9/group) for echocardiography. Halo reduced fibrosis. As a consequence, there was muscle repair and damage was reduced. There were functional improvements and disease progression was slowed. There was resolution of pre-existing fibrosis and reduction of new collagen synthesis. This treatment could improve quality of life and lengthen the lifespan of DMD patients.

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

Biomaterials are used in many different areas. Often, after implantation, severe host reactions occur which cause the malfunction or failure of the device. In our study, we wanted to investigate the mechanism of biomaterial-induced fibrosis. We focused on three areas: i) the relationship between inflammation and fibrosis after implantation, ii) the role that the SMAD3 gene plays, and iii) how MRL mice react to biomaterials. After implantation, acute inflammation occurs immediately. In pathological fibrosis, it has traditionally been believed that the inflammation is linked to the downstream fibrosis, though this theory has been challenged recently. In our project, we did not observe a direct relationship between intentionally induced inflammation and biomaterial-induced fibrosis. We did observe the dependency of the host reaction on the type of implanted biomaterial. The SMAD3 gene is tightly linked to the pro-fibrotic cytokine TGF-(beta). The SMAD3 protein mediates the TGF-(beta) pathway intracellularly. It was found in pulmonary fibrosis, SMAD3 knockout (KO) mice had lower production of collagen. In our project, we did not observe a difference in cellular behaviour on the surface of the implanted biomaterial between wild-type (WT) and SMAD3 KO mice. We did observe a difference in the production of TGF-(beta)1. This could be a clue that biomaterial-induced fibrosis has more than one mechanism/pathway that is not dependent on TGF-(beta). In our last project, we studied MRL mice that showed potential in scarless wound healing. We observed a higher production of MMP-2, MMP-9 and TGF-(beta)1. Histologically, however, we did not see a difference in cellular behaviour between MRL and C57BL/6 mice. Our results open up the possibilities of different mechanisms and pathways in biomaterial-induced fibrosis. Future studies of cytokines and specific cells could help us further understand the process of encapsulation of the implanted biomaterials. / Thesis / Master of Applied Science (MASc)

No description available.

En este trabajo se determino la frecuencia de las mutaciones ΔF508, G542X, G551D y R553X, en el gen cftr de pacientes diagnosticados con fibrosis quística (FQ) del Instituto Especializado de Salud del Niño. Participaron doce niños del servicio de neumología diagnosticados con FQ, en cada caso los padres de los pacientes firmaron un consentimiento informado, previo a su inclusión en el estudio. Se tomaron muestras de leucocitos de sangre venosa para extraer ADN genómico y se amplificaron regiones específicas del gen cftr por la reacción en cadena de la polimerasa con cebadores específicos diseñados para detectar las mutaciones: ΔF508 en el exón 10; y G542X, G551D y R553X en el exón 11. Los productos amplificados fueron cortados con las enzimas MboI, Bst O1, Hinc II y MboI respectivamente. Se identificaron: un paciente homocigoto para la ΔF508, cuatro pacientes heterocigotos ΔF508/OTRA, un paciente homocigoto para la G542X, y seis pacientes OTRA/OTRA. Las mutaciones G551D y R553X no fueron detectadas en este trabajo. Las frecuencias alélica para las mutaciones ΔF508 y G542X fueron 25% y 8.3% respectivamente. / In this study we determined the frequency of the mutations ΔF508, G542X, G551D and R553X, in the CFTR gene of patient diagnosed with cystic Fibrosis (CF) of the “Instituto Especializado de Salud del Niño”. Study the DNA of twelve individuals diagnosed with CF, all of them taken care of in the Pneumology Service of the “Instituto Especializado de Salud del Niño”. In each case the parents of the patients signed an informed consent, previous to their include in the study. Genomic DNA was extracted from leukocytes that it was isolated of a sample of blood, then were amplified by PCR by specific primers for the exon 10 (Mutation ΔF508) and exon 11 (Mutations G542X, G551D and R553X). The products of amplification were analyzed by restriction enzymes MboI, BstO1 and Hind II respectively. We identify a patient homozygote for it ΔF508, four patients heterozygote ΔF508/OTHER, one patient homozygote for the G542X, and six patients OTHER / OTHER. The mutations G551D and R553X were not found. The mutation ΔF508 presented a allelic frequency of 25 %, whereas the mutation G542X was found in 8.3 %

Wei, Lihua. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 166-196). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Zhang, Yang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 179-201). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

En este trabajo se determino la frecuencia de las mutaciones ΔF508, G542X, G551D y R553X, en el gen cftr de pacientes diagnosticados con fibrosis quística (FQ) del Instituto Especializado de Salud del Niño. Participaron doce niños del servicio de neumología diagnosticados con FQ, en cada caso los padres de los pacientes firmaron un consentimiento informado, previo a su inclusión en el estudio. Se tomaron muestras de leucocitos de sangre venosa para extraer ADN genómico y se amplificaron regiones específicas del gen cftr por la reacción en cadena de la polimerasa con cebadores específicos diseñados para detectar las mutaciones: ΔF508 en el exón 10; y G542X, G551D y R553X en el exón 11. Los productos amplificados fueron cortados con las enzimas MboI, Bst O1, Hinc II y MboI respectivamente. Se identificaron: un paciente homocigoto para la ΔF508, cuatro pacientes heterocigotos ΔF508/OTRA, un paciente homocigoto para la G542X, y seis pacientes OTRA/OTRA. Las mutaciones G551D y R553X no fueron detectadas en este trabajo. Las frecuencias alélica para las mutaciones ΔF508 y G542X fueron 25% y 8.3% respectivamente. / In this study we determined the frequency of the mutations ΔF508, G542X, G551D and R553X, in the CFTR gene of patient diagnosed with cystic Fibrosis (CF) of the “Instituto Especializado de Salud del Niño”. Study the DNA of twelve individuals diagnosed with CF, all of them taken care of in the Pneumology Service of the “Instituto Especializado de Salud del Niño”. In each case the parents of the patients signed an informed consent, previous to their include in the study. Genomic DNA was extracted from leukocytes that it was isolated of a sample of blood, then were amplified by PCR by specific primers for the exon 10 (Mutation ΔF508) and exon 11 (Mutations G542X, G551D and R553X). The products of amplification were analyzed by restriction enzymes MboI, BstO1 and Hind II respectively. We identify a patient homozygote for it ΔF508, four patients heterozygote ΔF508/OTHER, one patient homozygote for the G542X, and six patients OTHER / OTHER. The mutations G551D and R553X were not found. The mutation ΔF508 presented a allelic frequency of 25 %, whereas the mutation G542X was found in 8.3 %

Thesis (Ph.D.) - University of Queensland, 2006. / Includes bibliography.

Long thought to be irreversible, it is now clear that liver fibrogenesis is a dynamic process, with scar tissue capable of being remodelled as well as deposited. Macrophages have been shown to have a critical role in both liver fibrogenesis and fibrosis resolution. Whilst previous work has identified a Ly-6Chi hepatic macrophage population, derived from recruitment of inflammatory monocytes, as being the main pro-fibrogenic population, the nature and phenotype of the pro-resolution macrophage subset is unknown. In this thesis, I sought to identify and characterise this restorative hepatic macrophage. I established a reversible murine model of liver fibrosis using CCl4. At the time of initiation of fibrosis regression, Ly-6Clo CD11bhi F4/80int hepatic macrophages represented the most numerous macrophage population and the principal expresser of matrix degrading MMP enzymes. Depletion of this population in CD11b-diphtheria toxin (DTR) mice prevented fibrosis resolution. Subsequent, adoptive transfer and in situ labelling experiments, demonstrated that this restorative macrophage population derives from inflammatory monocytes, a common origin to the pro-fibrotic Ly-6Chi hepatic macrophage subset, indicating a switch in macrophage phenotype in situ to form the restorative phenotype. Characterisation of FACS-sorted restorative and pro-fibrogenic liver macrophage subsets using gene expression profiling demonstrated higher expression of pro-resolution genes and lower expression of pro-fibrotic genes in restorative macrophages, which also upregulated a number of genes involved in phagocytosis. Confocal microscopy confirmed that restorative macrophages showed evidence of prior phagocytosis. This could be replicated in vitro, where feeding macrophages with cellular debris resulted in matrix-degrading properties analogous to those seen in vivo, which was dependent on activation of the ERK signalling cascade. This effect was also demonstrated with the phagocytosis of liposomes in vitro. Finally, the administration of liposomes to CCl4-injured mice in vivo induced phagocytosis, causing an increase in hepatic restorative macrophage number and accelerating fibrosis regression. Hence, I have been able to identify and characterise the restorative hepatic macrophage and have utilised these data to develop a novel method to alter macrophage phenotype in vivo and accelerate the resolution of liver fibrosis and restoration of normal tissue architecture.