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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

Modifying function and fibrosis of cardiac and skeletal muscle from mdx mice

van Erp, Christel January 2005 (has links)
Duchenne Muscular Dystrophy (DMD) is a fatal condition occurring in approximately 1 in 3500 male births and is due to the lack of a protein called dystrophin. Initially DMD was considered a skeletal myopathy, but the pathology and consequences of cardiomyopathy are being increasingly recognised. Fibrosis, resulting from continual cycles of degeneration of the muscle tissues followed by inadequate regeneration of the muscles, is progressive in both cardiac and skeletal dystrophic muscle. In the heart fibrosis interferes with contractility and rhythm whereas it affects contractile function and causes contractures in skeletal muscles. This study utilised the mdx mouse which exhibits a pathological loss of muscle fibres and fibrosis characteristic of DMD, to examine a range of mechanisms that can influence muscle function and fibrosis. Ageing and workload both appear to contribute to the development of dystrophic features in cardiac and skeletal muscle of the mdx mouse. Therefore the effect of eccentric exercise on cardiac and skeletal muscle was examined in older mdx mice. Mice ran in 30 minute sessions for five months, 5 days per week. Downhill treadmill running did not exacerbate the contractile function or fibrosis of the mdx heart or the EDL, SOL or diaphragm muscles suggesting that cytokines influence function and fibrosis to a greater extent than workload alone. The role of the cytokine TGF-beta was examined by treating mdx mice with the TGF-beta antagonist pirfenidone at 0.4, 0.8 or 1.2 per cent in drinking water for six months. Pirfenidone improved cardiac contractility (P<0.01) and coronary flow (P<0.05), to levels comparable to control mice, despite no reduction in cardiac fibrosis. Pirfenidone did not reduce fibrosis or improve function in skeletal muscle. A deficiency of neuronal nitric oxide synthase (nNOS) in DMD and mdx mice causes a lowered production of nitric oxide indicating that the substrate of nNOS, l-arginine, may be beneficial to cardiac and skeletal muscle function in mdx mice. Oral l-arginine (5 mg/g bw) improved cardiac contractility, coronary flow and reduced cardiac fibrosis (P<0.05) without improving skeletal muscle function or fibrosis. In contrast, 10 mg/g bw l-arginine improved cardiac function and coronary flow (P<0.01), despite also elevating cardiac collagen. This increment in collagen was prevented by co-administration of prednisone. The experiments described in this dissertation reveal for the first time that pharmacological treatments in mdx mice can improve cardiac structure and function. Further elucidation of the optimum time and doses of such treatments may result in future pharmacological treatments to improve cardiac function and fibrosis in DMD.
392

Living with muscular dystrophy : Illness experience, activities of daily living, coping, quality of life and rehabilitation

Nätterlund, Birgitta January 2001 (has links)
<p>The overall aim was to study and gain knowledge about what it means to live with muscular dystrophy and to study rehabilitation from the patient's perspective, among adults with muscular dystrophy in three Swedish counties: Örebro, Östergötland and Norrbotten. The thesis comprises two qualitative and three quantitative studies. Thirty interviews about illness experience were subjected to content analysis and 37 interviews about perceived support in rehabilitation were analysed according to phenomenological guidelines. Data were also collected by the Assessment of Problem-focused Coping (APC), the ADL Staircase, the Self-report ADL, the Mental Adjustment to Cancer Scale, the Sickness Impact Profile, the Psychosocial well-being questionnaire and the Quality of Life Profile. The APC was developed for assessment of problem-focused coping and also covers questions concerning the extent to which activities are experienced as problems and satisfaction with activities. The result shows that the experience of illness is largely similar in the three diagnostic groups (proximal MD, Myotonic muscular dystrophy, Myopathia distalis tarda hereditaria). The persons reported many restrictions of everyday activities, most often in mobility and transportation. Over half were dependent on other people in activities of daily living, and the illness was experienced mainly as having negative consequences for everyday life. A lower quality of life may be partly explained by a reduced capacity for activities. Problem-focused coping was used only to a limited extent, and 'Fighting spirit' was the dominant coping strategy. Rehabilitation was experienced as very valuable, particularly the education about the muscle disease, technical aids, grants and physical training. Over a five-year period, disability and quality of life of the study participants deteriorated significantly, and the dependence on other people increased. </p>
393

Living with muscular dystrophy : Illness experience, activities of daily living, coping, quality of life and rehabilitation

Nätterlund, Birgitta January 2001 (has links)
The overall aim was to study and gain knowledge about what it means to live with muscular dystrophy and to study rehabilitation from the patient's perspective, among adults with muscular dystrophy in three Swedish counties: Örebro, Östergötland and Norrbotten. The thesis comprises two qualitative and three quantitative studies. Thirty interviews about illness experience were subjected to content analysis and 37 interviews about perceived support in rehabilitation were analysed according to phenomenological guidelines. Data were also collected by the Assessment of Problem-focused Coping (APC), the ADL Staircase, the Self-report ADL, the Mental Adjustment to Cancer Scale, the Sickness Impact Profile, the Psychosocial well-being questionnaire and the Quality of Life Profile. The APC was developed for assessment of problem-focused coping and also covers questions concerning the extent to which activities are experienced as problems and satisfaction with activities. The result shows that the experience of illness is largely similar in the three diagnostic groups (proximal MD, Myotonic muscular dystrophy, Myopathia distalis tarda hereditaria). The persons reported many restrictions of everyday activities, most often in mobility and transportation. Over half were dependent on other people in activities of daily living, and the illness was experienced mainly as having negative consequences for everyday life. A lower quality of life may be partly explained by a reduced capacity for activities. Problem-focused coping was used only to a limited extent, and 'Fighting spirit' was the dominant coping strategy. Rehabilitation was experienced as very valuable, particularly the education about the muscle disease, technical aids, grants and physical training. Over a five-year period, disability and quality of life of the study participants deteriorated significantly, and the dependence on other people increased.
394

Identification du gène Anoctamine 5 responsable d'une nouvelle forme récessive de dystrophie musculaire des ceintures

Bolduc, Véronique 10 1900 (has links)
Les dystrophies musculaires des ceintures (ou limb-girdle muscular dystrophy, LGMD) sont un groupe hétérogène de dystrophies musculaires chez l’adulte et sont définies par une atrophie et une faiblesse progressive qui surviennent dans les muscles proximaux. Chez une cohorte canadienne-française, nous avons précédemment décrit une nouvelle forme récessive, désignée LGMD2L et marquée par une atrophie asymétrique du quadriceps, que nous avions cartographiée au chromosome 11p12-p13 grâce à des analyses de liaison. L’objectif de ce projet de thèse était de raffiner l’intervalle candidat, puis d’identifier et de caractériser le gène muté responsable de la LGMD2L. Grâce à une cartographie par homozygotie de polymorphismes de nucléotide simple (SNPs) réalisée sur une grande famille consanguine, nous avons redéfini l’intervalle candidat à une région du chromosome 11p14.3-p15.1. Par séquençage de l’ADN génomique et complémentaire au gène Anoctamine 5 (ANO5) inclus dans cet intervalle, nous avons identifié trois mutations, chez autant de familles: une substitution créant un site d’épissage aberrant, une insertion d’un nucléotide et une mutation faux-sens. Les deux premières mutations étaient associées à une hausse de la dégradation de l’ARN messager médiée par une troncation prématurée. Nous avons également identifié des mutations ANO5 chez une seconde dystrophie musculaire de type distal cartographiant au même locus que la LGMD2L, nommée MMD3, et dont la manifestation initiale était une faiblesse des mollets, mais qui pouvait progresser vers une atrophie des quadriceps. Une réparation membranaire défective avait été observée chez les fibroblastes de deux patients MMD3, suggérant un rôle pour ANO5 dans ce mécanisme. La localisation et la fonction d’ANO5 dans le muscle sont inconnues, mais cette protéine fait partie d’une famille conservée de protéines à huit domaines transmembranaires, les Anoctamines, dont certains membres sont des transporteurs chloriques activés par le calcium. Les résultats de nos études d’immunofluorescence suggèrent qu’ANO5 se localise peu au sarcolemme, mais plutôt à une structure intracellulaire qui suit la ligne Z des myofibrilles. De façon étonnante, cette localisation était préservée chez un patient LGMD2L porteur homozygote de la mutation d’épissage, en dépit du fait que cette dernière était considérée comme une mutation nulle. Néanmoins, nous avons identifié un épissage alternatif de l’exon 15 qui se produisait sur une proportion des transcrits porteurs de la mutation d’épissage, ce qui rétablirait le cadre de lecture, soulignant la complexité de la régulation de l’épissage d’ANO5 et laissant croire que la LGMD2L pourrait être causée par une perte de fonction partielle, et non complète, d’ANO5. Des études subséquentes par des groupes européens ont montré que les anoctaminopathies 5 sont une cause fréquente de dystrophies musculaires des ceintures chez l’adulte. Notre découverte de mutations au gène Anoctamine 5 a mis en évidence une nouvelle classe de protéines importantes pour la biologie du muscle et a ouvert la voie à de nouvelles pistes pour étudier les mécanismes par lesquels un défaut de réparation membranaire progresse en une dystrophie musculaire. / Limb-girdle muscular dystrophies (LGMD) encompass a broad spectrum of muscular dystrophies in which the initial weakness arises in proximal muscles. We previously described in French-Canadian (FC) families a new form of LGMD characterized by asymmetrical quadriceps femoris atrophy, named LGMD2L, which we mapped to chromosome 11p12-p13 using linkage analyses. The objectives of this thesis project were to refine the candidate interval, identify and characterize the LGMD2L gene. Using single nucleotide polymorphisms (SNPs) homozygosity mapping in a large consanguineous family, we narrowed down the LGMD2L candidate interval to a region on chromosome 11p14.3-p15.1, and identified three mutations in the Anoctamin 5 (ANO5) gene located in the interval. These mutations consisted of a missense, a one-bp duplication and a splice site mutation. We demonstrated that the latter two triggered the nonsense-mediated RNA decay pathway. In addition, we identified ANO5 mutations in cases affected by a non-dysferlin Miyoshi muscular dystrophy mapped also to chromosome 11, termed MMD3. In two MMD3 families of European descent, patients presented with calf weakness as the initial symptoms, sometimes evolving to quadriceps atrophy. Fibroblasts from one MMD3 family were shown to be defective for membrane repair. ANO5 localization and function in muscle are unknown, but it is a member of the conserved Anoctamin family of proteins with eight transmembrane domains, of which some function as calcium-activated chloride channel. Our immunofluorescence studies on longitudinal muscle sections suggest that ANO5 is not importantly localized to the sarcolemma, but rather to a structure following the Z-line. To our surprise, this localization was preserved for a LGMD2L patient homozygous for the splice site mutation, previously considered as a null mutation. By studying the splicing isoforms in this patient, we observed that skipping of exon 15 occurs on a proportion of transcripts, in addition to the aberrant splicing caused by the mutation. This alternative splicing event would recover the reading frame, thus underlining the complexity of ANO5 splicing and suggesting that LGMD2L could be the consequence of a partial, rather than complete, loss-of-function. Subsequent studies by other groups have shown that anoctaminopathies 5 are a common cause of adult-onset LGMD. Our discovery of ANO5 mutations has shed light on a new class of proteins important for the muscle biology and opened new research avenues to study how defective membrane repair progresses into muscular dystrophies.
395

Charakterisierung von Mausmutanten als Modellsysteme für hereditäre Zapfendystropien

Stieger, Susann 23 November 2011 (has links) (PDF)
Die Zapfenphotorezeptoren (ZPR) sind verantwortlich für das Scharf- und Farbensehen. Ein totaler Funktionsverlust der ZPR, welcher beim Menschen zur Achromatopsie führt, hat eine Degeneration der ZPR zur Folge. Die pathologischen Vorgänge, die zur Degeneration der ZPR führen sind noch nicht restlos entschlüsselt worden. Zur Analyse der ZPR-Degeneration werden Tiermodelle genutzt, wobei bisher nur wenige Tiermodelle vorhanden sind. Ziel dieser Arbeit ist die Untersuchung und Charakterisierung von Mausmodellen, die Mutationen in funktionell bedeutsamen Genen der ZPR tragen. Hierbei handelt es sich entweder um ein weiteres potentielles Kandidatengen für ZPR-Dystrophien, das SLC24A2 Gen, oder um das PDE6C Gen, welches als ursächlich für Achromatopsie identifiziert wurde. Die Tiere der verschiedenen Mauslinien wurden anhand ihrer Ohrkennung genotypisiert und für die verschiedenen molekularbiologischen Verfahren euthanasiert. Von den Augen wurde entweder das gesamte Auge, das eye cup, oder die Netzhaut weiterverarbeitet. Es wurde eine Methode zur Anrei¬cherung der ZPR mit fluorescence activated cell sorting (FACS) erarbeitet. Des Weiteren kamen Techniken auf der DNA-, RNA- und Protein- Ebene (PCR, RT-PCR, Klonieren, Western blot) sowie histologische und immunhistologische Techniken zur Anwendung. Die Tiere wurden in vivo mithilfe von bildgebenden Verfahren (Scanning Laser Ophthalmology (SLO)) untersucht und funktionell durch die Elektroretinographie (ERG) charakterisiert. Für diese Studie wurde die Cone-GFP (die grünes fluoreszierendes Protein in den ZPR produziert) Mauslinie zur Entwicklung der ZPR-Anreicherung eingesetzt und analysiert. Die slc24a2ENU-Maus¬mutante wurde extern hergestellt, wobei durch eine ENU-induzierte Mutagenese eine Punktmutation im slc24a2-Gen, welches für den NCKX2 Austauscher kodiert, an Position 1722 (c.1722g>t) gene¬riert wurde. Als weiteres Mausmodell wird die spontan aufgetretene Mausmutante cpfl1 (cone photo¬receptor function loss 1) untersucht, die zwei unterschiedliche Mutationen im pde6c-Gen besitzt. Durch Kreuzen dieser Mauslinien untereinander und mit der Trα -/- Mauslinie (knock-out Mutation der Stäbchen Transducin α-Untereinheit) wurden die Doppelmutanten Linien slc24a2ENUxCone-GFP, slc24a2ENUxTrα-/- und cpfl1xCone-GFP hergestellt und untersucht. Bei Cone-GFP Mäusen konnten ZPR mittels FACS angereichert und gezielt untersucht werden. In der angereicherten ZPR-Population wurde bei RT-PCR Analysen zum einen nur eine Spleißvariante des NCKX2-Austauschers detektiert, während bei RT-PCR Analysen von ganzen Augen mehrere Spleißvarianten des NCKX2-Austauschers gefunden wurden. Zum Zweiten wurden weitere Mitglie¬der der NCKX-Familie in der angereicherten ZPR-Population (NCKX-1, 4) detektiert. Bei der slc24a2ENU-Mausmutante konnte die Mutation im slc24a2-Gen sowohl auf DNA- als auch auf RNA- Ebene nachgewiesen werden, jedoch nicht auf Proteinebene. Sowohl bei morphologischen (SLO und Histologie) als auch funktionellen (ERG) Untersuchungen wurden keine Unterschiede zwischen Wildtyp und Mutante in der Retina erkannt. Mithilfe der SLO wurde bei allen Tieren eine verlängerte Persistenz der arteria hyaloidea beobachtet. Das ERG war bei der slc24a2xTrα-/- Dop¬pelmutanten gegenüber der reinen Trα-/- ohne Veränderung. Bei den slc24a2ENUxCone GFP Mäusen und den reinen Cone-GFP Mäusen konnte im Alter von einem Jahr keine Amplitude mehr im ERG gemessen werden. Bei der SLO (bei beiden Doppelmutanten) wurden bei einigen Mäusen autofluo¬reszierende Punkte, so genannte „AF-dots“ beobachtet. Eine Ursache hierfür konnte nicht erbracht werden. Vergleichende genomische DNA-Untersuchungen von Intron 4 des pde6c Gens zwischen der cpfl1-Maus und dem Wildtyp C57Bl/6 zeigten bei der cpfl1-Maus eine im Vorfeld bereits auf RNA-Ebene beschriebene 116bp Insertion als Anteil einer 1522bp großen genomischen Insertion ist. Zusätzlich wurde eine 1bp Deletion im Exon 7 des pde6c Gens bei der cpfl1-Maus detektiert (c.1042delT). Beide Mutationen bedingen eine Verschiebung des Leserasters (frame shift), das wiederum zu einem verfrühten Stopcodon führt (p.E289fsX297 und p.L348fsX362). Vergleichende RT-PCR Untersu¬chungen der pde6c Transkripte zwischen der cpfl1-Maus mit ihrem Parentalstamm BALB/c erbrach¬ten, dass beide die 116bp Insertion tragen. Bei der ERG Untersuchung der cpfl1-Maus (im Alter von drei und sechs Wochen) konnte keine ZPR-Antwort registriert werden. Bei einer vergleichenden SLO-Verlaufsstudie (3., 4., 6. und 8. Lebenswoche) zwischen der Cone-GFP und der Doppelmutanten cpfl1xCone-GFP Maus zeigte sich, dass die Anzahl der ZPR zu Beginn der Studie gleich sind, im weiteren Verlauf bei der Doppelmutante immer stärker abnehmen und mit 8 Wochen nur noch im ventralen Bereich vorhanden sind. Es konnte in dieser Arbeit gezeigt werden, dass die Cone-GFP Maus ein potentiell sehr wichtiges Mausmodell werden kann, um weiterführende Grund-lagenforschung an ZPR zu ermöglichen. Zum einen können ZPR durch FACS angereichert werden und zum anderen ist eine eindeutige und einfache Darstellung der ZPR in vivo durch die SLO-Technik möglich. Jedoch ist es wichtig, den Untersuchungszeitpunkt innerhalb der ersten 2 Monate anzusetzen, da die ZPR der Cone-GFP Maus danach fortschreitend degenerieren. Aufgrund der RT-PCR Untersuchung der NCKX-Familie in der angereicherten ZPR-Population der Cone-GFP Maus konnten weitere Mitglieder der NCKX Austauscher Familie in den ZPR identifiziert werden, wodurch die Aussage, dass der NCKX2-Austauscher die einzige Möglichkeit darstellt, um Ca2+-Ionen aus dem Außensegment der ZPR zu schleusen, relativiert werden muss. Die Slc24a2ENU-Mausmutante zeigt keinen offensichtlichen degenerativen retinalen Phänotyp. Die einzige Besonderheit stellt die sporadisch auftretende persistierende Arteria hyaloidea dar. Der bei einigen doppelmutanten Tieren auftretende retinale Phänotyp, der „AF-dots“-Phänotyp, ist möglich¬erweise auf den Stammhintergrund (C3H) zurückzuführen. Weitere Untersuchungen sind zur Klärung dieser Frage notwendig. Die cpfl1-Maus ist das erste Modell für Achromatopsie, bei dem die Pathologie durch Mutationen im pde6c-Gen ausgelöst wird. Das cpfl1-Allel besitzt zwei unterschiedliche Mutationen, die beide zu einem verfrühten Abbruch der Proteinsynthese führen. Durch RNA-Untersuchungen konnte gezeigt werden, dass die cpfl1-Maus sich nur in der 1 bp Deletion von dem Parentalstamm BALB/c unterscheidet. Jedoch scheinen beide Mutationen einen Anteil an der Herausbildung des Phänotyps der cpfl1-Maus zu haben. Im Rahmen der vergleichenden Verlaufsstudie mit Doppelmutanten cpfl1xCone-GFP wurde als pathologischer Vorgang eine Degeneration und keine Aplasie der ZPR nachgewiesen, da im Alter von 3 Wochen noch eine normale Anzahl an ZPR vorhanden ist.
396

CRISPR-Cas9 Mediated Restoration of Dystrophin Expression and Inhibition of Myostatin: A Novel Gene Therapy for Duchenne Muscular Dystrophy

Rangan, Apoorva 01 January 2016 (has links)
Duchenne Muscular Dystrophy (DMD) is an X-linked recessive genetic disease, caused by a frame-shift mutation in the dystrophin gene. Current gene therapies for DMD target dystrophin transcripts in existing skeletal and cardiac muscle, rather than adipose and fibrotic tissues. These approaches may be unable to repair muscle functionality in DMD patients who have already undergone extensive muscle damage and wasting. Thus, successful DMD therapies must consider the underlying genetic cause and pathology. Inhibition of the gene myostatin, a negative regulator of muscle growth, has been shown to ameliorate muscle loss. Here, the CRISPR-Cas9 gene-editing platform is proposed to restore dystrophin expression and inhibit myostatin as a novel gene therapy in DMD patient derived induced pluripotent stem cells. Successful CRISPR-Cas9 mediated gene editing would be determined using PCR amplification, western blot analysis, immunofluorescence staining, and off target sequence analysis in differentiated skeletal muscle cells.
397

Treino de baixa intensidade retarda a deposi??o de fibras col?genas no m?sculo gastrocn?mio distr?fico de modelo mdx

Pinto, Priscilla Avelino Ferreira 09 August 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-03-13T19:28:36Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) priscilla_avelino_ferreira_pinto.pdf: 1920663 bytes, checksum: c9bd6e512c60dc9f7254711669d80fe0 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-03-29T11:52:20Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) priscilla_avelino_ferreira_pinto.pdf: 1920663 bytes, checksum: c9bd6e512c60dc9f7254711669d80fe0 (MD5) / Made available in DSpace on 2018-03-29T11:52:21Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) priscilla_avelino_ferreira_pinto.pdf: 1920663 bytes, checksum: c9bd6e512c60dc9f7254711669d80fe0 (MD5) Previous issue date: 2017 / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Introdu??o: A Distrofia Muscular de Duchenne (DMD) ? marcada pela falta da distrofina, e sua aus?ncia leva a altera??es mec?nicas da fibra muscular, resultando num processo de necrose muscular e altera??es histol?gicas. O treinamento f?sico de baixa intensidade vem sendo empregado como forma de retardar a progress?o da DMD, entretanto, ainda n?o se sabe os par?metros ben?ficos ao m?sculo distr?fico. Assim, objetivou-se elucidar os efeitos do exerc?cio terap?utico de baixa intensidade em esteira no m?sculo esquel?tico distr?fico do modelo mdx nos par?metros morfol?gicos, na morfometria dos marcadores de les?o muscular, da fibrose musclar e na constitui??o da matriz extracelular pelos col?genos tipo I e III. Metodologia: Foram estudados tr?s grupos: camundongos mdx exerc?cio (mdxE), mdx sedent?rio (mdxC) e controle saud?veis (Cc) (n=8/grupo). O grupo mdxE foi estimulado a correr em esteira horizontal motorizada para ratos, em baixa intensidade, 9m/min por 30 minutos/dia, 3 vezes/semana, por 8 semanas. Ap?s o protocolo de exerc?cio foi realizada a eutan?sia dos animais e coletado o m?sculo gastrocn?mio. Foi realizada a colora??o Hematoxilina-Eosina para an?lise dos marcadores de les?o muscular: N?cleo Central e Di?metro M?nimo de Feret; a rea??o de Picrossirius red para an?lise das fibras col?genas na fibrose muscular e a imuno-localiza??o das fibras col?genas tipo I e III. Resultados: Foram observadas altera??es histol?gicas distr?ficas caracter?sticas nos grupos mdxE e mdxC e feixes de fibras col?genas espessas no grupo mdxC. A imuno-histoqu?mica revelou presen?a de col?geno do tipo I principalmente no grupo mdxC. N?o houve diferen?a significativa entre os grupos mdxE e mdxC para fibras com n?cleo central e coeficiente de varia??o do Di?metro m?nimo de Feret. O grupo mdxE n?o apresentou diferen?a significativa em rela??o ao Cc para a porcentagem da ?rea de fibras col?genas na fibrose muscular. Conclus?es: O treino de baixa intensidade reduz a deposi??o de fibras col?genas na fibrose muscular, com fibras delgadas do col?geno tipo I e n?o altera os marcadores de les?o muscular. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Reabilita??o e Desempenho Funcional, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Introduction: Duchenne muscular dystrophy (DMD) is marked by lack of dystrophin, and its absence leads to muscle fiber rupture, resulting in muscular necrosis and histological changes. Physical training of low intensity has been used to delay the progression of DMD, however, parameters of the dystrophic muscle are not yet known. The objective of this study was to elucidate the effects of a treadmill low intensity exercise on morphology, morphometric parameters of the muscle injury markers and the composition of the extracellular matrix by type I and III collagens of the dystrophic skeletal muscle of the mdx model. Methods: Three groups were studied: exercised mdx (mdxE), sedentary mdx (mdxC) and healthy controls (Cc) (n =8/group). The mdxE group was stimulated to run on a motorized horizontal treadmill for rats, with a low intensity (9 m/min for 30 minutes/day, 3 times/week) for 8 weeks. After the exercise protocol, the animals were euthanized and the gastrocnemius muscle was collected. Hematoxylin-Eosin staining was performed for analysis of muscle injury markers, Central Nucleus and Minimum Diameter of Feret, Picrossirius red reaction for analysis of collagen fibers in muscle fibrosis and immuno-localization of type I and III collagen fibers. Results: Dystrophic histopathological changes were observed in the mdxE and mdxC groups and thicker collagen fiber bundles in the mdxC group. Immunohistochemistry revealed the presence of type I collagen mainly in the mdxC group. There was no significant difference between the mdxE and mdxC groups for fibers with centrally located nuclei and coefficient of variation of the Minimum Feret Diameter. The mdxE group showed no significant difference in relation to Cc for the percentage of the area of collagen fibers in muscle fibrosis. Conclusions: The low intensity training reduced the deposition of collagen fibers in muscle fibrosis with thin fibers of type I collagen and did not alter the markers of muscle injury.
398

Identificação e avaliação da distribuição alélica de repetições do trinucleotídeo CTG no gene DMPK em indivíduos saudáveis e em pacientes com distrofia miotônica tipo 1

Rodrigues, Luiza Paulsen January 2016 (has links)
O gene DMPK (Dystrophia Myotonica-Protein Kinase) humano está localizado no locus 19q13.3, sendo dividido em 15 éxons, com uma região polimórfica de repetições CTG em sua região 3’ não traduzida. Indivíduos normais apresentam de 5 a 34 repetições CTG. Indivíduos com alelos com mais de 50 repetições CTG apresentam distrofia miotônica tipo 1 (DM1), uma doença multissistêmica de herança autossômica dominante. Os sintomas incluem miotonia, fraqueza muscular progressiva, hipogonadismo, entre outros. Neste trabalho, a distribuição dos alelos do gene DMPK em indivíduos controles foi estabelecida em duas populações (brasileira e peruana), por meio de PCR convencional utilizando iniciadores fluorescentes e repeat-primed PCR. O protocolo confirmou 93 casos não relacionados de DM1 (76 brasileiros e 17 peruanos) após a análise de 224 amostras com suspeita clínica. A distribuição e as frequências dos alelos normais foram estabelecidas em ambas as populações e os alelos mais frequentes foram 5 (frequência = 0,326) e 13 (frequência = 0,545) repetições de CTG em brasileiros e peruanos, respectivamente. A frequência de alelos normais grandes (aqueles com mais de 45 repetições CTGs) foi de 9% e 4% em brasileiros e peruanos, respectivamente. Neste trabalho é descrita a análise molecular de DM1 na maior coorte brasileira até o momento e é o primeiro trabalho em que foi analisada a população peruana. A distribuição e a frequência de alelos normais também foram estabelecidas e alelos mutáveis foram detectados entre os indivíduos controles. / The human DMPK (Dystrophia Myotonica-Protein Kinase) gene is located at 19q13.3 locus, being organized into 15 exons, with a polymorphic tract of CTG repeats in its 3' untranslated region. Normal individuals have 5-34 CTG repeats. Individuals carrying alleles with more than 50 CTG repeats have myotonic dystrophy type 1 (DM1), a multisystemic disease of autosomal dominant inheritance. Symptoms include myotonia, progressive muscle weakness, hypogonadism, among others. Disease prevalence is variable among populations and may be related to the frequency of large normal alleles (those with more than 18 CTG repeats). Here we determined here the distribution of alleles of DMPK gene in healthy and DM1 patients in Brazilian and Peruvian populations, through conventional PCR using fluorescent primers and repeat-primed PCR. This protocol confirmed 93 unrelated cases of DM1 (76 Brazilians and 17 Peruvians) following the analysis of 224 samples with clinical suspicion. Distribution and frequencies of normal alleles were also established in both populations and the most frequent alleles were 5 (frequency of 0.326) and 13 (frequency of 0.545) CTG repeats in Brazilians and Peruvians, respectively. Frequency of large normal alleles (those with more than 45 CTG repeats) was established to be 9% and 4% in Brazilians and Peruvians, respectively. This report describes molecular analysis of DM1 in the largest Brazilian cohort so far, and is the first to report any data in the Peruvian population. Distribution and frequency of normal alleles were also established and mutable alleles were detected among controls.
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Identificação e avaliação da distribuição alélica de repetições do trinucleotídeo CTG no gene DMPK em indivíduos saudáveis e em pacientes com distrofia miotônica tipo 1

Rodrigues, Luiza Paulsen January 2016 (has links)
O gene DMPK (Dystrophia Myotonica-Protein Kinase) humano está localizado no locus 19q13.3, sendo dividido em 15 éxons, com uma região polimórfica de repetições CTG em sua região 3’ não traduzida. Indivíduos normais apresentam de 5 a 34 repetições CTG. Indivíduos com alelos com mais de 50 repetições CTG apresentam distrofia miotônica tipo 1 (DM1), uma doença multissistêmica de herança autossômica dominante. Os sintomas incluem miotonia, fraqueza muscular progressiva, hipogonadismo, entre outros. Neste trabalho, a distribuição dos alelos do gene DMPK em indivíduos controles foi estabelecida em duas populações (brasileira e peruana), por meio de PCR convencional utilizando iniciadores fluorescentes e repeat-primed PCR. O protocolo confirmou 93 casos não relacionados de DM1 (76 brasileiros e 17 peruanos) após a análise de 224 amostras com suspeita clínica. A distribuição e as frequências dos alelos normais foram estabelecidas em ambas as populações e os alelos mais frequentes foram 5 (frequência = 0,326) e 13 (frequência = 0,545) repetições de CTG em brasileiros e peruanos, respectivamente. A frequência de alelos normais grandes (aqueles com mais de 45 repetições CTGs) foi de 9% e 4% em brasileiros e peruanos, respectivamente. Neste trabalho é descrita a análise molecular de DM1 na maior coorte brasileira até o momento e é o primeiro trabalho em que foi analisada a população peruana. A distribuição e a frequência de alelos normais também foram estabelecidas e alelos mutáveis foram detectados entre os indivíduos controles. / The human DMPK (Dystrophia Myotonica-Protein Kinase) gene is located at 19q13.3 locus, being organized into 15 exons, with a polymorphic tract of CTG repeats in its 3' untranslated region. Normal individuals have 5-34 CTG repeats. Individuals carrying alleles with more than 50 CTG repeats have myotonic dystrophy type 1 (DM1), a multisystemic disease of autosomal dominant inheritance. Symptoms include myotonia, progressive muscle weakness, hypogonadism, among others. Disease prevalence is variable among populations and may be related to the frequency of large normal alleles (those with more than 18 CTG repeats). Here we determined here the distribution of alleles of DMPK gene in healthy and DM1 patients in Brazilian and Peruvian populations, through conventional PCR using fluorescent primers and repeat-primed PCR. This protocol confirmed 93 unrelated cases of DM1 (76 Brazilians and 17 Peruvians) following the analysis of 224 samples with clinical suspicion. Distribution and frequencies of normal alleles were also established in both populations and the most frequent alleles were 5 (frequency of 0.326) and 13 (frequency of 0.545) CTG repeats in Brazilians and Peruvians, respectively. Frequency of large normal alleles (those with more than 45 CTG repeats) was established to be 9% and 4% in Brazilians and Peruvians, respectively. This report describes molecular analysis of DM1 in the largest Brazilian cohort so far, and is the first to report any data in the Peruvian population. Distribution and frequency of normal alleles were also established and mutable alleles were detected among controls.
400

Fenotypická charakterizace zdravé lidské rohovky a její změny při zadní polymorfní dystrofií rohovky / Phenotypical characterization of the healthy human cornea and the alterations caused by posterior polymorphous corneal dystrophy

Reinštein Merjavá, Stanislava January 2011 (has links)
Purpose: The aim of this work was to characterize the healthy human cornea and the cornea of patients suffering from posterior polymorphous corneal dystrophy (PPCD) using different antibodies. Despite the fact that PPCD is a very rare disorder, one of the largest groups of PPCD patients in the world comes from the Czech Republic. This offers us the opportunity to investigate the changes on the clinical, cellular and molecular levels. Material and Methods: A collection of 25 control corneas as well as 16 pathological corneas from PPCD patients were used. Epithelial (cytokeratins) and mesothelial markers (mesothelin, calbindin 2, HBME-1 protein) were detected in all layers of the healthy corneas using immunocyto- and immunohistochemistry. The expression of all markers was confirmed using molecular methods as well (RT-PCR and Western blot). Changes in the expression of cytokeratins and changes in the extracellular matrix structure (collagen IV and VIII) were studied in the PPCD corneas. Combined fluorescent immunohistochemistry with fluorescence in situ hybridization were used in order to characterize the origin of abnormal cells on the posterior graft surface, which cause the recurrence of the PPCD after penetrating keratoplasty surgery. Results: Changes in the cytokeratin expression (strong...

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