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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.
11

Lysyl hydroxylases:characterization of mouse lysyl hydroxylases and generation of genetically modified lysyl hydroxylase 3 mouse lines

Ruotsalainen, H. (Heli) 31 May 2005 (has links)
Abstract Lysyl hydroxylase (EC 1.14.11.4, procollagen-lysine, 2-oxyglutarate, 5-dioxygenase, Plod) catalyzes the hydroxylation of certain lysine residues in collagens and in other proteins with collagenous domains. Three lysyl hydroxylase isoforms have been cloned from human and rat. The importance of lysyl hydroxylase 1 in collagen biosynthesis is demonstrated by the heritable disorder, Ehlers-Danlos syndrome type VI, which is characterized by joint laxity, progressive scoliosis, muscle hypotonia, scleral fragility and rupture of the ocular globe. An alternatively spliced form of lysyl hydroxylase 2 seems to function as a telopeptide lysyl hydroxylase. Lysyl hydroxylase 3 has three enzyme activities, lysyl hydroxylase, hydroxylysyl galactosyltransferase (EC 2.4.1.50), and galactosylhydroxylysyl glucosyltransferase (EC 2.4.1.66) activities that have been demonstrated earlier with in vitro experiments. In this thesis study, the cDNAs of mouse lysyl hydroxylase isoforms 1, 2 and 3 were cloned and characterized and the gene structures of lysyl hydroxylase 2, Plod2, and lysyl hydroxylase 3, Plod3, were determined. Mouse lysyl hydroxylase isoforms were found to be highly homologous to the corresponding human isoforms and they were approximately 60% identical with each other. The mouse Plod3 gene has 19 exons as do the human PLOD1 and PLOD3 genes, and mouse Plod2, like the human PLOD2, has 20 exons including one alternatively spliced extra exon. The mouse isoforms were also found to have distinct tissue distributions. Phylogenetic analysis revealed that the lysyl hydroxylase genes have evolved from an ancestral gene through two gene duplication events. Lysyl hydroxylase 3 was demonstrated to be the oldest isoform, which is further supported by the association of glycosyltransferase activities with lysyl hydroxylase 3 and with the only lysyl hydroxylase of Caenorhabditis elegans. The roles of the different enzyme activities of lysyl hydroxylase 3 were determined in vivo by generating three genetically modified lysyl hydroxylase 3 mouse lines. The analysis of these mouse lines demonstrated that lysyl hydroxylase 3 possesses at least lysyl hydroxylase and glucosyltransferase activities in vivo and it functions as the main, if not the only glucosyltransferase during embryogenesis. The absence of lysyl hydroxylase 3 and, especially, its glucosyltransferase activity results in the abnormal glycosylation of type IV collagen, and thus causes a severe basement membrane defect leading to death during early development. By contrast, lysyl hydroxylase activity had no effect on embryonic development, but caused changes in the structure of the epidermal basement membrane and changes in collagen fibril organization and probably in their interactions.
12

Insights into healing response in severe sepsis from a connective tissue perspective:a longitudinal case-control study on wound healing, collagen synthesis and degradation, and matrix metalloproteinases in patients with severe sepsis

Gäddnäs, F. (Fiia) 24 August 2010 (has links)
Abstract Sepsis is a major challenge for healing responses maintaining homeostasis. Coagulation and inflammation are activated at the whole-body level, even in undamaged tissues. Despite constantly growing knowledge and advances in care, high mortality in severe sepsis remains. It was hypothesised that tissue regeneration processes may also be altered in severe sepsis. The study population consisted of 44 patients with severe sepsis and 15 healthy controls. Serum samples were obtained during ten days of severe sepsis and twice again, three months and six months later. Experimental suction blisters were performed twice during severe sepsis and at 3 and 6 months. Serum samples were obtained and suction blisters were induced once in controls. Biochemical analyses were performed to assess the level of procollagen I and III aminoterminal propeptides (PINP, PIIINP), reflecting the synthesis of corresponding collagens; in serum and suction blister fluid. In addition collagen I degradationproduct in serum was measured. Physiological measurements of transepidermal water loss and blood flow were done in order to evaluate the re-epithelisation rate and blood flow in an experimental wound. Levels of matrix metalloproteinases (MMPs) 2, 8 and 9 were measured from serum and suction blister fluid. Decrease in water evaporation from an experimental blister wound was slower in sepsis than in controls. On the fourth day the sepsis patients had higher blood flow in the blister wound than the controls (both in the healing wound and in the newly induced wound). The procollagen III aminoterminal propeptide (PIIINP) levels were increased in serum in severe sepsis, whereas procollagen I aminoterminal propeptide (PINP) levels were not, making up a pronounced PIIINP/PINP ratio. PIIINP and PINP levels were associated with disease severity and outcome. In addition, collagen I degradation measured with ICTP assay was increased in severe sepsis and PINP/ICTP ratio was lower. Furthermore, the overall protein concentration and PINP and PIIINP levels were low in suction blister fluid, which implies that the balance of the extracellular matrix consistence is disturbed in uninjured skin in severe sepsis. Then again in survivors the levels of PINP and PIIINP were up-regulated at three months but returned to normal by six months. MMP-9 levels in serum and skin blister fluid were lower in severe sepsis than in controls during the ten days studied. The MMP-2 levels were found to be increased both in serum and in skin blister fluid in severe sepsis in comparison to the controls and MMP-2 was associated with disease severity and outcome. MMP-8 was increased in serum and in skin blister fluid. In conclusion, the balance of collagen turnover is altered in severe sepsis in serum and skin and epidermal re-epithelisation is delayed. The levels of MMP-2 and MMP-8 are increased whereas levels of MMP-9 are depressed.
13

Structure and function of the polypyrimidine region of the rat [alpha]1 (I) procollagen gene promoter

Ririe, Seth S., January 2000 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 133-147). Also available on the Internet.
14

Expression of lysyl hydroxylases and characterization of a novel disorder caused by mutations in the lysyl hydroxylase 3 gene

Salo, A. (Antti) 18 August 2009 (has links)
Abstract Collagens and collagenous proteins undergo several post-translational modifications that are important for their structure and functions. Lysine hydroxylation produces hydroxylysines, which are important for collagen cross-link formation and provide attachment sites for galactose and glucosylgalactose. Glycosylated hydroxylysines are crucial for embryonic development and the assembly of certain collagen types. They may also facilitate interactions between collagen and adjacent molecules as well as control the diameter of collagen fibrils. Lysine hydroxylation is catalyzed by three lysyl hydroxylases (LH1, LH2 and LH3). In addition to lysyl hydroxylase activity, LH3 possesses collagen galactosyltransferase (GT) and glucosyltransferase (GGT) activities. In this study, polyclonal antibodies against the lysyl hydroxylase isoforms were produced for protein level studies to localize the expression and understand the functions of the different isoenzymes. The results indicated ubiquitous expression during embryonic development compared to the more restricted, cell and tissue specific expression patterns observed in adult mouse tissues. Differences were seen also in the alternative splicing of LH2 during embryogenesis and between tissue types. Analyses of the subcellular localization revealed that LH3 is also present in extracellular space. Tissue and cell specific differences were noted in the distribution of LH3 between cellular compartments. Substrate analysis suggested an additional and novel role for LH3 as an enzyme catalyzing lysine modifications of collagenous proteins in the extracellular space. The importance of LH1 and LH2 has been highlighted in Ehlers-Danlos type VI and Bruck syndromes, respectively. In this study, the lysyl hydroxylase 3 gene was linked to a heritable disorder for the first time. Urinary screening revealed a patient that lacked a glucosylgalactosyl derivative of a pyridinium cross-link. The GGT activity levels measured from the patient’s serum and lymphoblastoid cells were also reduced, which suggested a defect in the lysyl hydroxylase 3 gene. Genetic analyses revealed two mutations, one in each allele of LH3 in this compound heterozygous patient. Recombinant mutant proteins showed defects in lysyl hydroxylase and collagen glycosyltransferase activities, respectively. In conclusion, it was shown that a defect in LH3 catalyzed modifications leads to a novel disorder, which shares features with many other connective tissue disorders.
15

Biomarkers of Knee Joint Healing in Adolescents with Anterior Cruciate Ligament Injuries

Ek Orloff, Lisa 25 February 2022 (has links)
Objective: Anterior cruciate ligament (ACL) injuries are increasing in adolescents and increase the risk for early-onset knee osteoarthritis (OA). Biomarkers can be a non-invasive measure to assess physiological properties following knee injury or trauma. The objective of this thesis was to i) perform a systematic review to determine the most studied biomarkers of knee healing following ACL reconstruction (ACLR), and age of these patients, and ii) explore the feasibility of measuring these biomarkers in adolescents with ACL injuries. Design: Studies were included if i) participants underwent ACLR, and ii) at least one biomarker of healing was measured. Participant age, sample(s) collected, and biomarker(s) studied were recorded. Interleukin-6 (IL-6), c-terminal crosslinking telopeptide of type II collagen (CTX-II) and procollagen type II collagen propeptide (PIICP) were then measured using ELISA in adolescents prior to ACLR in urine (u) and synovial fluid (sf). Spearman’s Rho (rs) coefficients were calculated to determine the association between uCTX-II/sfCTX-II, and uIL-6/sfIL-6. A ratio of PIICP: CTX-II was calculated to represent the ratio of cartilage synthesis to degradation. Results: The review produced six studies evaluating healing following ACLR. IL-6 and CTX-II were the most studied (3/6 studies), and only one study included adolescents (age 19.6±4.5). Due to multiple undetectable biomarker levels, we could only report rs for uCTX-II/sfCTX-II (rs = -.200, p-value = .800, n=4). We also reported a ratio for sfPIICP: sfCTX-II (23.06 ±19.23). Conclusion: Exploring biomarkers in adolescents was motivated by their unique physiology due to puberty, and this was the first study to do so. The findings from this pilot study indicate that further analysis is required to determine optimal sample preparation. This will allow for reliable results while studying the feasibility of these biomarkers during ACLR recovery. This insight can ensure more informed decision making by clinicians clearing patients for return-to-activity.
16

Hypoxia-inducible factor hydroxylases are oxygen sensors in the brain /

Dalgard, Clifton Lee. January 2005 (has links) (PDF)
Thesis (Ph. D.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
17

Expressão de genes e de proteínas envolvidos na biossíntese da matriz extracelular no tecido vaginal de mulheres com e sem prolapso de órgãos pélvicos / Expression of genes and proteins related to the extracellular matrix biogenesis in vaginal tissue of women with and without pelvic organ prolapse

Bortolini, Maria Augusta Tezelli [UNIFESP] 25 May 2011 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-25. Added 1 bitstream(s) on 2015-08-11T03:26:12Z : No. of bitstreams: 1 Publico-12837a.pdf: 1258726 bytes, checksum: a7e0f280ec3b88f2f775c2b325704cd7 (MD5). Added 1 bitstream(s) on 2015-08-11T03:26:12Z : No. of bitstreams: 2 Publico-12837a.pdf: 1258726 bytes, checksum: a7e0f280ec3b88f2f775c2b325704cd7 (MD5) Publico-12837b.pdf: 2043061 bytes, checksum: 4edc37b57c73112ae7353868a78233ca (MD5). Added 1 bitstream(s) on 2015-08-11T03:26:12Z : No. of bitstreams: 3 Publico-12837a.pdf: 1258726 bytes, checksum: a7e0f280ec3b88f2f775c2b325704cd7 (MD5) Publico-12837b.pdf: 2043061 bytes, checksum: 4edc37b57c73112ae7353868a78233ca (MD5) Publico-12837c.pdf: 1773766 bytes, checksum: 56addbd5601cb4e7336afb640ed56fe8 (MD5) / Objetivo: O prolapso de órgãos pélvicos (POP) resulta da falha na sustentação do assoalho pélvico, e anormalidades do tecido conjuntivo podem estar envolvidas na etiologia e/ou na progressão da disfunção. Analisar-se-á a expressão diferencial de genes e de proteínas que participam da biossíntese do colágeno e da elastina: lisil oxidases (LOXs), fibulina-5, fibrilinas-1 e -2 e pró-colágeno C proteinase (PCP/BMP1), no tecido vaginal de mulheres sem e com POP acentuado consoante seu estado hormonal. Casuística e Métodos: Durante a histerectomia total, biópsias de parede vaginal anterior foram obtidas de mulheres caucasianas na pré-menopausa (fase proliferativa do ciclo menstrual) e na pós-menopausa com POP acentuado (POPQ estadio III e IV), e de controles assintomáticas (POPQ 0). RNAm e proteínas totais foram extraídos usando Trizol e RIPA Buffer, e os genes e proteínas de interesse quantificados por RT-PCR em tempo real e Imunobloting, respectivamente. As seguintes análises comparativas foram realizadas: (1) expressão dos genes e das proteínas da família LOX (LOX e LOXL1-4), fibulina-5 e fibrilinas- 1 e -2 em pacientes na pré-menopausa com e sem POP; (2) expressão do gene e da proteína PCP/BMP1 em pacientes na pré- e pós-menopausa com POP, e respectivos controles. Os testes de Wilcoxon signed-rank e Fisher foram usados para as análises estatísticas (p<0.05). Resultados: Obtivemos amostras de 15 pacientes e 11 controles na pré-menopausa para o estudo (1), e 39 pacientes na pré-menopausa (POP=23 e Controle=16) e 18 na pósmenopausa (POP=13 e Controle=5) para o estudo (2). A partir das análises, observamos (1) diminuição significativa na expressão dos genes LOX, LOXL1 e LOXL3, bem como nas proteínas LOX e LOXL3 no tecido vaginal de pacientes POP na pré-menopausa comparadas com mulheres assintomáticas (p<0.05); (2) hipoexpressão do gene PCP/BMP1 nos tecidos vaginais de mulheres com POP acentuado comparadas com controles, tanto na prémenopausa como na pós-menopausa (ambos p=0.01); redução significativa das isoformas 130kDa, 92,5kDa e 82,5kDa da PCP/BMP1 no tecido vaginal de pacientes na pósmenopausa (p=0.01), bem como hiperexpressão da isoforma 130kDa nas mulheres com POP acentuado na pré-menopausa (p=0.009), comparadas com as respectivas controles. Conclusão: As expressões das enzimas LOXs e pró-colágeno C proteinase estão alteradas no tecido vaginal de mulheres com POP, e são moduladas pelo estado hormonal. A alteração na regulação destas enzimas, envolvidas na biossíntese da matriz extracelular, pode contribuir para deficiente síntese do tecido conjuntivo e do suporte vaginal, e estar envolvida no desenvolvimento do POP. / Objective: Pelvic organ prolapse (POP) results from the failure of pelvic floor support, and connective tissue abnormalities may be involved in the etiology and/or progression of the dysfunction. We aimed to analyze the differential expression of genes and proteins related to the collagen and elastin biogenesis: lysyl oxidases (LOXs), fibulin-5, fibrillin -1 and -2, and procollagen C proteinase (PCP/BMP1) in vaginal tissue of women without and with advanced POP controlled by hormonal status. Materials and Methods: During total hysterectomy, anterior vaginal wall biopsies were obtained from Caucasian premenopausal women (proliferative phase of menstrual cycle) and postmenopausal women with severe POP (POPQ stage III and IV) and asymptomatic controls (POPQ 0). Total mRNA and protein were extracted using Trizol and RIPA buffer, and the genes and proteins of interest were quantified by real-time RT-PCR and Immunoblotting, respectively. The following analysis were performed: (1) expression of LOX family genes and proteins (LOX and LOXL1-4), fibulin-5, fibrillin-1 and -2 in premenopausal women with and without POP; (2) PCP/BMP1 gene and protein expression in vaginal tissue of pre- and postmenopausal POP women, and respective controls. Wilcoxon signed-rank and Fisher tests were used for statistical analysis (p<0.05). Results: Samples from 15 premenopausal patients and 11 controls were obtained for study (1); 39 premenopausal (POP=23 and Control=16) and 18 postmenopausal women samples (POP=13 and Control=5) for study (2). We observed: (1) significant decrease in expression of LOX, LOXL1 and LOXL3 genes, as well as LOX and LOXL3 proteins in vaginal tissue of premenopausal POP patients compared with asymptomatic women (p<0.05); (2) PCP/BMP1 gene downregulation in the vagina of women with severe POP compared with controls, in both premenopausal and postmenopausal phase (both p=0.01); significant reduction of 130 kDa, 92.5 kDa and 82.5 kDa PCP/BMP1 isoforms in vaginal tissue of postmenopausal patients (p=0.01), and 130 kDa isoform upregulation in premenopausal women with severe POP (p=0.009), compared with their respective controls. Conclusion: The expression of LOXs enzymes and PCP/BMP1 are altered in vaginal tissue of women with severe POP, and are modulated by hormonal status. Dysregulation of these enzymes involved in the extracellular matrix biogenesis may contribute to impaired tissue and vaginal support, and may be involved in POP development. / TEDE / BV UNIFESP: Teses e dissertações

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